The "paperclip method" - it does more than you think, even on '96 cars!
01-10-2010, 03:13 PM
#41
Race Director
Its in there maybe the highlight and color change will help..
Make sure you have a piece of paper and something to write with...it will take a while to cycle threw all of the modules.....
So to spell it OUT jumper the pins and turn the key on....it should cycle through automatically ....good luck.
Originally Posted by LouisvilleLT4
;
-----Using diagnostic mode-----
To enter the diagnostic mode, you simply ground the diagnostic pin on your car's diagnostic connector (located near the driver's knees). Various DLC connectors were used throughout the C4's life, all with different pinouts; on '94-'96 cars, you connect the fourth pin from the left in each of the two rows of pins to one another, with a paperclip or some other conductor.
When you turn the ignition to "run," you will now be in diagnostic mode, which uses the LCD screen and the DIC (driver information center) buttons for input and output. You may start and drive the car while in diagnostic mode; in fact, the car has to be running for some of the functions to be meaningful. The only disadvantage is you will not be able to see your normal gauges while in this mode since the LCD screen will be in use.
When you start diagnostic mode, the LCD will show you any codes stored in the car's various computers. In '96, Module 1 is the CCM (main/dash computer), 4 is the PCM (engine computer, doesn't show up in '96), 7 is the RTD (computer-controlled shock absorbers, if you've got them), 9 is the EBTCM (antilock brake and traction computer), and A is the DERM (air bag computer). These are cycled through one at a time, with dashes indicating the end of codes for that module. A "C" prefix means the code is currently active, meaning that the relevant parameters are out of range right now; an "H" means the code has been stored in history but is not currently active.
Unlike the car's other electronic systems, such as PCM, ABS, air bags, etc., there is no specific "CCM" lamp to indicate a malfunction when one is present. Instead, the CCM flashes the word "SYS" three times every once in a while on the LCD whenever there are active CCM codes present. If the code thrown is one that involves only the security system, the "SECURITY" lamp will illuminate instead, or they will both flash together if it involves the Fuel Enable Data Stream.
Upon entering diagnostic mode, as mentioned, you will first see a listing of diagnostic codes for each module. Afterwards, you will enter the menu (or you can press any information center buttons to skip to the menu). Did you know there was a menu? I didn't, until I read the FSM.You'll know you're in the menu when you see the number "1.0". The first digit, before the decimal point, refers to which module you are talking to at the moment, as numbered above. The second digit indicates the menu item. Item .0 means that computer is awaiting instructions. Item .1 displays any codes for that module and .7 clears them. This applies to all of the car's computers/modules. Note that any non-CCM codes will always show up with the "H" as in history, since the CCM does not know whether or not they are currently active.
-----Using diagnostic mode-----
To enter the diagnostic mode, you simply ground the diagnostic pin on your car's diagnostic connector (located near the driver's knees). Various DLC connectors were used throughout the C4's life, all with different pinouts; on '94-'96 cars, you connect the fourth pin from the left in each of the two rows of pins to one another, with a paperclip or some other conductor.
When you turn the ignition to "run," you will now be in diagnostic mode, which uses the LCD screen and the DIC (driver information center) buttons for input and output. You may start and drive the car while in diagnostic mode; in fact, the car has to be running for some of the functions to be meaningful. The only disadvantage is you will not be able to see your normal gauges while in this mode since the LCD screen will be in use.
When you start diagnostic mode, the LCD will show you any codes stored in the car's various computers. In '96, Module 1 is the CCM (main/dash computer), 4 is the PCM (engine computer, doesn't show up in '96), 7 is the RTD (computer-controlled shock absorbers, if you've got them), 9 is the EBTCM (antilock brake and traction computer), and A is the DERM (air bag computer). These are cycled through one at a time, with dashes indicating the end of codes for that module. A "C" prefix means the code is currently active, meaning that the relevant parameters are out of range right now; an "H" means the code has been stored in history but is not currently active.
Unlike the car's other electronic systems, such as PCM, ABS, air bags, etc., there is no specific "CCM" lamp to indicate a malfunction when one is present. Instead, the CCM flashes the word "SYS" three times every once in a while on the LCD whenever there are active CCM codes present. If the code thrown is one that involves only the security system, the "SECURITY" lamp will illuminate instead, or they will both flash together if it involves the Fuel Enable Data Stream.
Upon entering diagnostic mode, as mentioned, you will first see a listing of diagnostic codes for each module. Afterwards, you will enter the menu (or you can press any information center buttons to skip to the menu). Did you know there was a menu? I didn't, until I read the FSM.You'll know you're in the menu when you see the number "1.0". The first digit, before the decimal point, refers to which module you are talking to at the moment, as numbered above. The second digit indicates the menu item. Item .0 means that computer is awaiting instructions. Item .1 displays any codes for that module and .7 clears them. This applies to all of the car's computers/modules. Note that any non-CCM codes will always show up with the "H" as in history, since the CCM does not know whether or not they are currently active.
Make sure you have a piece of paper and something to write with...it will take a while to cycle threw all of the modules.....
So to spell it OUT jumper the pins and turn the key on....it should cycle through automatically ....good luck.
Last edited by aboatguy; 01-10-2010 at 03:16 PM.
01-10-2010, 04:03 PM
#42
Burning Brakes
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Its in there maybe the highlight and color change will help..
Make sure you have a piece of paper and something to write with...it will take a while to cycle threw all of the modules.....
So to spell it OUT jumper the pins and turn the key on....it should cycle through automatically ....good luck.
Make sure you have a piece of paper and something to write with...it will take a while to cycle threw all of the modules.....
So to spell it OUT jumper the pins and turn the key on....it should cycle through automatically ....good luck.
01-10-2010, 04:39 PM
#44
Race Director
H 63 means its a history code... 12 should flash 3 times at the beginning and end of each modules cycle.....
Here's what shows up on Code 63- Right bank heated O2 sensor (1994-95). Check wiring and connections to the O2 sensor, open circuit indicated. If wiring verifies ok, replace sensor. Not my words but from a trouble code site.
Good luck
Mike
Here's what shows up on Code 63- Right bank heated O2 sensor (1994-95). Check wiring and connections to the O2 sensor, open circuit indicated. If wiring verifies ok, replace sensor. Not my words but from a trouble code site.
Good luck
Mike
01-10-2010, 04:49 PM
#45
Burning Brakes
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H 63 means its a history code... 12 should flash 3 times at the beginning and end of each modules cycle.....
Here's what shows up on Code 63- Right bank heated O2 sensor (1994-95). Check wiring and connections to the O2 sensor, open circuit indicated. If wiring verifies ok, replace sensor. Not my words but from a trouble code site.
Good luck
Mike
Here's what shows up on Code 63- Right bank heated O2 sensor (1994-95). Check wiring and connections to the O2 sensor, open circuit indicated. If wiring verifies ok, replace sensor. Not my words but from a trouble code site.
Good luck
Mike
01-10-2010, 05:29 PM
#46
Race Director
Mike
01-10-2010, 07:00 PM
#47
Burning Brakes
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01-10-2010, 07:28 PM
#48
Race Director
Maybe....if the O2 sensor issue is making it run pig rich...but I would do the wiring/connector/sensor checks prior to throwing parts at it. I'd run a datalog and watch what the O2s were doing, but I have the equipment for that.
11-14-2011, 04:05 AM
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I am posting this to clear some things up about the "paperclip" trick as it applies to later model C4's ('94-'96), and I just want to make sure nobody is in the dark about all the various features of their car's built-in diagnostic mode. I will show that it does a lot more than display codes (it's got a menu!), and I will show you what the "SYS" message means, and I also hope to clear up some major misinformation.
Specifically, there have been numerous rumors that the 1996 cars have no diagnostic mode. You can enter the '96 diagnostic mode, but the rumors say it's only a holdover from previous years and that everything shown on the screen is garbage. This is false. The 1996 cars DO have an elaborate and functional diagnostic mode, with only one major change.
Our cars have numerous computers (it calls them "modules") networked together, one of which is the PCM, which controls the engine. The root of the rumors lies in the fact that in '96, new laws mandated the PCM's protocol to change to OBD-II, which used a standardized four-digit numbering scheme for "check engine" codes, which is too big to fit on the LCD. Rather than find some other way to display that many digits, GM decided to say screw it and deleted the functions that read/clear PCM codes from the diagnostic mode. The PCM simply no longer shows up at all among the modules listed.
They forgot to mention this little tidbit in the service manual, which confused a lot of people into thinking that the whole CCM chapter does not apply to '96 cars, but other than that one detail, it does. GM did not change any of the functions involving other modules (CCM, EBTCM, etc), nor did those functions get corrupted by the switch to OBD-II; they all still show up and function correctly. Thus the majority of the diagnostic mode's power is still there in '96. I know because I checked.
-----Using diagnostic mode-----
To enter the diagnostic mode, you simply ground the diagnostic pin on your car's diagnostic connector (located near the driver's knees). Various DLC connectors were used throughout the C4's life, all with different pinouts; on '94-'96 cars, you connect the fourth pin from the left in each of the two rows of pins to one another, with a paperclip or some other conductor.
When you turn the ignition to "run," you will now be in diagnostic mode, which uses the LCD screen and the DIC (driver information center) buttons for input and output. You may start and drive the car while in diagnostic mode; in fact, the car has to be running for some of the functions to be meaningful. The only disadvantage is you will not be able to see your normal gauges while in this mode since the LCD screen will be in use.
When you start diagnostic mode, the LCD will show you any codes stored in the car's various computers. In '96, Module 1 is the CCM (main/dash computer), 4 is the PCM (engine computer, doesn't show up in '96), 7 is the RTD (computer-controlled shock absorbers, if you've got them), 9 is the EBTCM (antilock brake and traction computer), and A is the DERM (air bag computer). These are cycled through one at a time, with dashes indicating the end of codes for that module. A "C" prefix means the code is currently active, meaning that the relevant parameters are out of range right now; an "H" means the code has been stored in history but is not currently active.
Unlike the car's other electronic systems, such as PCM, ABS, air bags, etc., there is no specific "CCM" lamp to indicate a malfunction when one is present. Instead, the CCM flashes the word "SYS" three times every once in a while on the LCD whenever there are active CCM codes present. If the code thrown is one that involves only the security system, the "SECURITY" lamp will illuminate instead, or they will both flash together if it involves the Fuel Enable Data Stream.
Upon entering diagnostic mode, as mentioned, you will first see a listing of diagnostic codes for each module. Afterwards, you will enter the menu (or you can press any information center buttons to skip to the menu). Did you know there was a menu? I didn't, until I read the FSM.
You'll know you're in the menu when you see the number "1.0". The first digit, before the decimal point, refers to which module you are talking to at the moment, as numbered above. The second digit indicates the menu item. Item .0 means that computer is awaiting instructions. Item .1 displays any codes for that module and .7 clears them. This applies to all of the car's computers/modules. Note that any non-CCM codes will always show up with the "H" as in history, since the CCM does not know whether or not they are currently active.
The CCM has additional options on top of these; .2 and .3 let you cycle through the CCM's stored data and inputs, respectively, and option .4 lets you toggle each of its outputs manually (this part is fun).
To navigate the menu items, use the "gauges" and "trip odo" button. To navigate to the next or previous module, hold down the "fuel" or "trip" button for a second. To select a menu item, press "ENG MET."
One thing that I recommend doing at this point, is see if you have any EBTCM codes stored (module 9 in '96), and then delete them. You will hear the brake pressure modulator valves near the EBTCM click as it resets, and you might suddenly feel that your brakes feel and work much better than before. This was the case for me; I had a lateral accelerometer code, as well as a code from back when my Opti died making the tachometer go crazy. Neither code has come back since I cleared them, meaning that the presence of codes alone was enough to severely effect how my brake functions.
Now for the fun part: The CCM data, input, and outputs. These are options .2, .3, and .4 in the CCM module menu, respectively. After selecting any of these, press "eng met" to go to the next value and "fuel info" to go to the previous. The selections are:
Display CCM Data (Mode 1.2):
01 - Fuel Level (Gallons, tenths)
02 - Dimming Potentiometer
03 - Ambient Light Sensor
04 - Rear Defogger Timer
05 - Vehicle Speed
06 - Pass-Key
07 - Ignition Voltage
08 - Switched Voltage
09 - Cluster dimming
10 - LCD backlight dimming
11 - Radio & Climate dimming
12 - LED dimming
13 & 14 - Vehicle configuration
15 - Oil monitor count
16 - CCM version
Display CCM input status (Mode 1.3):
1 - PassKey fuel
2 - English/metric status
3 - Door key switch
4 - Right Door ajar
5 - Left door ajar
6 - key in ignition but in "off" or "acc" position
7 - hatch ajar
8 - Power door unlock
9 - Power door lock
10 - Parking lights
11 - Rear defogger input (car must be running)
12 - Seat belt switch
13 - High beam switch
14 - Low oil level switch
These values are either "1" or "0," and when toggled, the new value will be appended on to the old value (01 means it was 0 but is now 1).
Cycle CCM Outputs (Mode 1.4):
Selecting these options will manually activate the lights and sounds the CCM produces.
1 - Change oil light
2 - Check gauges indicator
3 - Fasten seatbelt indicator
4 - Security lamp
5 - High beam indicator
6 & 7 - chimes
8 - LCD blanking
9 - Defogger relay
10 - Courtesy lamp
11 - Low oil lamp
12 - Theft relay
13 - DAB relay
14 - door ajar light
15 - Horns (This will actually beep the horns, watch out!)
So there you have it; you can now dazzle and impress your friends with your car's diagnostic features, as well as test any of the circuits and systems in the interior. Please correct any factual errors I have made in this post, and if you know of any information that would be useful to add to this thread, so as to make it a centralized source for information about the late model CCM, let me know.
Specifically, there have been numerous rumors that the 1996 cars have no diagnostic mode. You can enter the '96 diagnostic mode, but the rumors say it's only a holdover from previous years and that everything shown on the screen is garbage. This is false. The 1996 cars DO have an elaborate and functional diagnostic mode, with only one major change.
Our cars have numerous computers (it calls them "modules") networked together, one of which is the PCM, which controls the engine. The root of the rumors lies in the fact that in '96, new laws mandated the PCM's protocol to change to OBD-II, which used a standardized four-digit numbering scheme for "check engine" codes, which is too big to fit on the LCD. Rather than find some other way to display that many digits, GM decided to say screw it and deleted the functions that read/clear PCM codes from the diagnostic mode. The PCM simply no longer shows up at all among the modules listed.
They forgot to mention this little tidbit in the service manual, which confused a lot of people into thinking that the whole CCM chapter does not apply to '96 cars, but other than that one detail, it does. GM did not change any of the functions involving other modules (CCM, EBTCM, etc), nor did those functions get corrupted by the switch to OBD-II; they all still show up and function correctly. Thus the majority of the diagnostic mode's power is still there in '96. I know because I checked.
-----Using diagnostic mode-----
To enter the diagnostic mode, you simply ground the diagnostic pin on your car's diagnostic connector (located near the driver's knees). Various DLC connectors were used throughout the C4's life, all with different pinouts; on '94-'96 cars, you connect the fourth pin from the left in each of the two rows of pins to one another, with a paperclip or some other conductor.
When you turn the ignition to "run," you will now be in diagnostic mode, which uses the LCD screen and the DIC (driver information center) buttons for input and output. You may start and drive the car while in diagnostic mode; in fact, the car has to be running for some of the functions to be meaningful. The only disadvantage is you will not be able to see your normal gauges while in this mode since the LCD screen will be in use.
When you start diagnostic mode, the LCD will show you any codes stored in the car's various computers. In '96, Module 1 is the CCM (main/dash computer), 4 is the PCM (engine computer, doesn't show up in '96), 7 is the RTD (computer-controlled shock absorbers, if you've got them), 9 is the EBTCM (antilock brake and traction computer), and A is the DERM (air bag computer). These are cycled through one at a time, with dashes indicating the end of codes for that module. A "C" prefix means the code is currently active, meaning that the relevant parameters are out of range right now; an "H" means the code has been stored in history but is not currently active.
Unlike the car's other electronic systems, such as PCM, ABS, air bags, etc., there is no specific "CCM" lamp to indicate a malfunction when one is present. Instead, the CCM flashes the word "SYS" three times every once in a while on the LCD whenever there are active CCM codes present. If the code thrown is one that involves only the security system, the "SECURITY" lamp will illuminate instead, or they will both flash together if it involves the Fuel Enable Data Stream.
Upon entering diagnostic mode, as mentioned, you will first see a listing of diagnostic codes for each module. Afterwards, you will enter the menu (or you can press any information center buttons to skip to the menu). Did you know there was a menu? I didn't, until I read the FSM.
You'll know you're in the menu when you see the number "1.0". The first digit, before the decimal point, refers to which module you are talking to at the moment, as numbered above. The second digit indicates the menu item. Item .0 means that computer is awaiting instructions. Item .1 displays any codes for that module and .7 clears them. This applies to all of the car's computers/modules. Note that any non-CCM codes will always show up with the "H" as in history, since the CCM does not know whether or not they are currently active.
The CCM has additional options on top of these; .2 and .3 let you cycle through the CCM's stored data and inputs, respectively, and option .4 lets you toggle each of its outputs manually (this part is fun).
To navigate the menu items, use the "gauges" and "trip odo" button. To navigate to the next or previous module, hold down the "fuel" or "trip" button for a second. To select a menu item, press "ENG MET."
One thing that I recommend doing at this point, is see if you have any EBTCM codes stored (module 9 in '96), and then delete them. You will hear the brake pressure modulator valves near the EBTCM click as it resets, and you might suddenly feel that your brakes feel and work much better than before. This was the case for me; I had a lateral accelerometer code, as well as a code from back when my Opti died making the tachometer go crazy. Neither code has come back since I cleared them, meaning that the presence of codes alone was enough to severely effect how my brake functions.
Now for the fun part: The CCM data, input, and outputs. These are options .2, .3, and .4 in the CCM module menu, respectively. After selecting any of these, press "eng met" to go to the next value and "fuel info" to go to the previous. The selections are:
Display CCM Data (Mode 1.2):
01 - Fuel Level (Gallons, tenths)
02 - Dimming Potentiometer
03 - Ambient Light Sensor
04 - Rear Defogger Timer
05 - Vehicle Speed
06 - Pass-Key
07 - Ignition Voltage
08 - Switched Voltage
09 - Cluster dimming
10 - LCD backlight dimming
11 - Radio & Climate dimming
12 - LED dimming
13 & 14 - Vehicle configuration
15 - Oil monitor count
16 - CCM version
Display CCM input status (Mode 1.3):
1 - PassKey fuel
2 - English/metric status
3 - Door key switch
4 - Right Door ajar
5 - Left door ajar
6 - key in ignition but in "off" or "acc" position
7 - hatch ajar
8 - Power door unlock
9 - Power door lock
10 - Parking lights
11 - Rear defogger input (car must be running)
12 - Seat belt switch
13 - High beam switch
14 - Low oil level switch
These values are either "1" or "0," and when toggled, the new value will be appended on to the old value (01 means it was 0 but is now 1).
Cycle CCM Outputs (Mode 1.4):
Selecting these options will manually activate the lights and sounds the CCM produces.
1 - Change oil light
2 - Check gauges indicator
3 - Fasten seatbelt indicator
4 - Security lamp
5 - High beam indicator
6 & 7 - chimes
8 - LCD blanking
9 - Defogger relay
10 - Courtesy lamp
11 - Low oil lamp
12 - Theft relay
13 - DAB relay
14 - door ajar light
15 - Horns (This will actually beep the horns, watch out!)
So there you have it; you can now dazzle and impress your friends with your car's diagnostic features, as well as test any of the circuits and systems in the interior. Please correct any factual errors I have made in this post, and if you know of any information that would be useful to add to this thread, so as to make it a centralized source for information about the late model CCM, let me know.
I would surely like to see all this computer data in some sort of alphabetical or procedural form. Is there such a manual or disc?
Herman
11-14-2011, 11:15 AM
#51
Le Mans Master
Let me see if I am on track here. I have never had a computerized vette until now. Don't you know I would buy a '96. You say these cars have numerous computers or modules. I am assuming that the PCM, which controls the engine was changed to the OBD-II to read out 4 digits because of new laws mandated the PCM's protocol. Does that mean that the "check engine" codes, which is too big to fit on the LCD were just removed? There is no engine codes in the '96? You stated that the information no longer shows up in certain modules, I think. I am trying to learn how to go about this inspection/deletion and or reset process from fellas like you. However, I do not wish to approach the car until I am very familiar with the step by step process necessary to accomplish some sort of success. I am very interested in your abilities and knowledge of these components. Rather than bother you with all the minut details......Is there something I might purchase that will allow me to read and re-read until some sort of mental assurance has been met?
I would surely like to see all this computer data in some sort of alphabetical or procedural form. Is there such a manual or disc?
Herman
I would surely like to see all this computer data in some sort of alphabetical or procedural form. Is there such a manual or disc?
Herman
If you have a specific issue please create a new post with details and we'll try to help you until you can get the FSM. After you get the FSM you may need more help to understand it. It gets easier as you use it though.
Good Luck!
11-14-2011, 06:53 PM
#52
Advanced
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Location: Spring Texas
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Your 96 is ODBII which means you can go to your favorite parts store and have them use an ODBII scanner to get the PCM codes. Or you can purchase one. As far as learning about how to troubleshoot and repair your corvette nothing, I mean NOTHING compares to the factory service manual. You can get a "new" one from the Helms website or look at eBay for one. you wat the books with the red covers, white covers are preliminary manuals and may not have all the corrections in them.
If you have a specific issue please create a new post with details and we'll try to help you until you can get the FSM. After you get the FSM you may need more help to understand it. It gets easier as you use it though.
Good Luck!
If you have a specific issue please create a new post with details and we'll try to help you until you can get the FSM. After you get the FSM you may need more help to understand it. It gets easier as you use it though.
Good Luck!
Thank you sooooooo much for this info. I'll get right on it and see where I can find a FSM. I'll go to the Helms if I can find it and look for the red covers. It'll take days to get it so I'll be reading all I can between now and then.
Thanks again for your support..........there is no other website with guys like this one.......Support is the key to a successful project.
H.G.
12-11-2011, 09:12 AM
#53
Instructor
Member Since: Sep 2003
Location: Attleborough Norfolk
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dtc fault on 94
My question is you say module 7 is the FX3 or SRC .
I am having a problem showing my codes on a faulty FX3 actuator but when i got into diagnostic mode then module 7 does not show up at all?
help?
JohnUKVetteNut
I am having a problem showing my codes on a faulty FX3 actuator but when i got into diagnostic mode then module 7 does not show up at all?
help?
JohnUKVetteNut
12-11-2011, 05:18 PM
#54
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Obdii
Your 96 is ODBII which means you can go to your favorite parts store and have them use an ODBII scanner to get the PCM codes. Or you can purchase one. As far as learning about how to troubleshoot and repair your corvette nothing, I mean NOTHING compares to the factory service manual. You can get a "new" one from the Helms website or look at eBay for one. you wat the books with the red covers, white covers are preliminary manuals and may not have all the corrections in them.
If you have a specific issue please create a new post with details and we'll try to help you until you can get the FSM. After you get the FSM you may need more help to understand it. It gets easier as you use it though.
Good Luck!
If you have a specific issue please create a new post with details and we'll try to help you until you can get the FSM. After you get the FSM you may need more help to understand it. It gets easier as you use it though.
Good Luck!
I purchased a OBDII from OBD.com and vata bing. It was so simple. I plugged into the DLC connector. This device has a plug to USB my laptop into the other end. I had my laptop on the software provided by OBD.com, up on the screen but had NOT clicked on start yet. The OBDII blinked repeatedly until the red row of lights blinking from DLC toward the USB finally turned into ONE green light. I clicked start on the software page and it connected automatically. I had purchased the FSM from Helms as you suggested. I was ready :-) The software displayed several modules and as I clicked on them........they gave a list of codes just as you said and provided for us. I went through each of the codes in each module to find that most were door ajar or parking brake not released or some other non-eventful code.
Anyway, at the last module I discovered my '96 wasn't such an electronic terror but instead a very useful menagery of helpful codes that can keep a novice on top of the issues that may crop up. My vette had to have a OS sensor replacement but that took about an hour and I was allowed to start the vehicle per the FSM, read the code, which was deleted and all is well.
I have only one question with this perfect little analysis process................How often should I perform this ritual? It is not difficult and very informative but I find myself wanting to hook up everytime I return from the local market..........I couldn't find anything in the FSM to indicate the repetitive check-up process....
It's fun, it's informational and re-assuring to know that everything on the motor and other places is being monitored and ready to inform one as to how well this machine is performing. I am so thankful for your information about this process. It lead me to a personal satisfaction with this vette and a kind of enlightenment to all the engineers that worked on providing us with a connection to our purchase.
Thank you so much and Happy Holidays
Last edited by hermangarner1; 12-11-2011 at 05:21 PM.
07-02-2012, 02:20 PM
#55
Racer
crap,
im confused,,, someone simplfi ,,i have a 96 i put a code reader on it and i have no codes,is it possiable i can see other codes that it wont see,,i keep getting a ltpsws and a seride controll,,,what do i short to ground and where do i see codes?[LIST]
07-03-2012, 12:11 PM
#56
Safety Car
Those two special controllers aren't tied into the engine control or CCM (body control module) at all- they are stand-alone boxes that work on their own. The ride control does look at the vehicle speed input, but doesn't interact with other black boxes. they have their own special test to get the codes out. a universal code reader won't get them to do their diagnostic- you need to jump the paperclip to the specific pin to activate those codes.
10-14-2013, 09:16 PM
#58
2nd Gear
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I am posting this to clear some things up about the "paperclip" trick as it applies to later model C4's ('94-'96), and I just want to make sure nobody is in the dark about all the various features of their car's built-in diagnostic mode. I will show that it does a lot more than display codes (it's got a menu!), and I will show you what the "SYS" message means, and I also hope to clear up some major misinformation.
Specifically, there have been numerous rumors that the 1996 cars have no diagnostic mode. You can enter the '96 diagnostic mode, but the rumors say it's only a holdover from previous years and that everything shown on the screen is garbage. This is false. The 1996 cars DO have an elaborate and functional diagnostic mode, with only one major change.
Our cars have numerous computers (it calls them "modules") networked together, one of which is the PCM, which controls the engine. The root of the rumors lies in the fact that in '96, new laws mandated the PCM's protocol to change to OBD-II, which used a standardized four-digit numbering scheme for "check engine" codes, which is too big to fit on the LCD. Rather than find some other way to display that many digits, GM decided to say screw it and deleted the functions that read/clear PCM codes from the diagnostic mode. The PCM simply no longer shows up at all among the modules listed.
They forgot to mention this little tidbit in the service manual, which confused a lot of people into thinking that the whole CCM chapter does not apply to '96 cars, but other than that one detail, it does. GM did not change any of the functions involving other modules (CCM, EBTCM, etc), nor did those functions get corrupted by the switch to OBD-II; they all still show up and function correctly. Thus the majority of the diagnostic mode's power is still there in '96. I know because I checked.
-----Using diagnostic mode-----
To enter the diagnostic mode, you simply ground the diagnostic pin on your car's diagnostic connector (located near the driver's knees). Various DLC connectors were used throughout the C4's life, all with different pinouts; on '94-'96 cars, you connect the fourth pin from the left in each of the two rows of pins to one another, with a paperclip or some other conductor.
When you turn the ignition to "run," you will now be in diagnostic mode, which uses the LCD screen and the DIC (driver information center) buttons for input and output. You may start and drive the car while in diagnostic mode; in fact, the car has to be running for some of the functions to be meaningful. The only disadvantage is you will not be able to see your normal gauges while in this mode since the LCD screen will be in use.
When you start diagnostic mode, the LCD will show you any codes stored in the car's various computers. In '96, Module 1 is the CCM (main/dash computer), 4 is the PCM (engine computer, doesn't show up in '96), 7 is the RTD (computer-controlled shock absorbers, if you've got them), 9 is the EBTCM (antilock brake and traction computer), and A is the DERM (air bag computer). These are cycled through one at a time, with dashes indicating the end of codes for that module. A "C" prefix means the code is currently active, meaning that the relevant parameters are out of range right now; an "H" means the code has been stored in history but is not currently active.
Unlike the car's other electronic systems, such as PCM, ABS, air bags, etc., there is no specific "CCM" lamp to indicate a malfunction when one is present. Instead, the CCM flashes the word "SYS" three times every once in a while on the LCD whenever there are active CCM codes present. If the code thrown is one that involves only the security system, the "SECURITY" lamp will illuminate instead, or they will both flash together if it involves the Fuel Enable Data Stream.
Upon entering diagnostic mode, as mentioned, you will first see a listing of diagnostic codes for each module. Afterwards, you will enter the menu (or you can press any information center buttons to skip to the menu). Did you know there was a menu? I didn't, until I read the FSM.
You'll know you're in the menu when you see the number "1.0". The first digit, before the decimal point, refers to which module you are talking to at the moment, as numbered above. The second digit indicates the menu item. Item .0 means that computer is awaiting instructions. Item .1 displays any codes for that module and .7 clears them. This applies to all of the car's computers/modules. Note that any non-CCM codes will always show up with the "H" as in history, since the CCM does not know whether or not they are currently active.
The CCM has additional options on top of these; .2 and .3 let you cycle through the CCM's stored data and inputs, respectively, and option .4 lets you toggle each of its outputs manually (this part is fun).
To navigate the menu items, use the "gauges" and "trip odo" button. To navigate to the next or previous module, hold down the "fuel" or "trip" button for a second. To select a menu item, press "ENG MET."
One thing that I recommend doing at this point, is see if you have any EBTCM codes stored (module 9 in '96), and then delete them. You will hear the brake pressure modulator valves near the EBTCM click as it resets, and you might suddenly feel that your brakes feel and work much better than before. This was the case for me; I had a lateral accelerometer code, as well as a code from back when my Opti died making the tachometer go crazy. Neither code has come back since I cleared them, meaning that the presence of codes alone was enough to severely effect how my brake functions.
Now for the fun part: The CCM data, input, and outputs. These are options .2, .3, and .4 in the CCM module menu, respectively. After selecting any of these, press "eng met" to go to the next value and "fuel info" to go to the previous. The selections are:
Display CCM Data (Mode 1.2):
01 - Fuel Level (Gallons, tenths)
02 - Dimming Potentiometer
03 - Ambient Light Sensor
04 - Rear Defogger Timer
05 - Vehicle Speed
06 - Pass-Key
07 - Ignition Voltage
08 - Switched Voltage
09 - Cluster dimming
10 - LCD backlight dimming
11 - Radio & Climate dimming
12 - LED dimming
13 & 14 - Vehicle configuration
15 - Oil monitor count
16 - CCM version
Display CCM input status (Mode 1.3):
1 - PassKey fuel
2 - English/metric status
3 - Door key switch
4 - Right Door ajar
5 - Left door ajar
6 - key in ignition but in "off" or "acc" position
7 - hatch ajar
8 - Power door unlock
9 - Power door lock
10 - Parking lights
11 - Rear defogger input (car must be running)
12 - Seat belt switch
13 - High beam switch
14 - Low oil level switch
These values are either "1" or "0," and when toggled, the new value will be appended on to the old value (01 means it was 0 but is now 1).
Cycle CCM Outputs (Mode 1.4):
Selecting these options will manually activate the lights and sounds the CCM produces.
1 - Change oil light
2 - Check gauges indicator
3 - Fasten seatbelt indicator
4 - Security lamp
5 - High beam indicator
6 & 7 - chimes
8 - LCD blanking
9 - Defogger relay
10 - Courtesy lamp
11 - Low oil lamp
12 - Theft relay
13 - DAB relay
14 - door ajar light
15 - Horns (This will actually beep the horns, watch out!)
So there you have it; you can now dazzle and impress your friends with your car's diagnostic features, as well as test any of the circuits and systems in the interior. Please correct any factual errors I have made in this post, and if you know of any information that would be useful to add to this thread, so as to make it a centralized source for information about the late model CCM, let me know.
Specifically, there have been numerous rumors that the 1996 cars have no diagnostic mode. You can enter the '96 diagnostic mode, but the rumors say it's only a holdover from previous years and that everything shown on the screen is garbage. This is false. The 1996 cars DO have an elaborate and functional diagnostic mode, with only one major change.
Our cars have numerous computers (it calls them "modules") networked together, one of which is the PCM, which controls the engine. The root of the rumors lies in the fact that in '96, new laws mandated the PCM's protocol to change to OBD-II, which used a standardized four-digit numbering scheme for "check engine" codes, which is too big to fit on the LCD. Rather than find some other way to display that many digits, GM decided to say screw it and deleted the functions that read/clear PCM codes from the diagnostic mode. The PCM simply no longer shows up at all among the modules listed.
They forgot to mention this little tidbit in the service manual, which confused a lot of people into thinking that the whole CCM chapter does not apply to '96 cars, but other than that one detail, it does. GM did not change any of the functions involving other modules (CCM, EBTCM, etc), nor did those functions get corrupted by the switch to OBD-II; they all still show up and function correctly. Thus the majority of the diagnostic mode's power is still there in '96. I know because I checked.
-----Using diagnostic mode-----
To enter the diagnostic mode, you simply ground the diagnostic pin on your car's diagnostic connector (located near the driver's knees). Various DLC connectors were used throughout the C4's life, all with different pinouts; on '94-'96 cars, you connect the fourth pin from the left in each of the two rows of pins to one another, with a paperclip or some other conductor.
When you turn the ignition to "run," you will now be in diagnostic mode, which uses the LCD screen and the DIC (driver information center) buttons for input and output. You may start and drive the car while in diagnostic mode; in fact, the car has to be running for some of the functions to be meaningful. The only disadvantage is you will not be able to see your normal gauges while in this mode since the LCD screen will be in use.
When you start diagnostic mode, the LCD will show you any codes stored in the car's various computers. In '96, Module 1 is the CCM (main/dash computer), 4 is the PCM (engine computer, doesn't show up in '96), 7 is the RTD (computer-controlled shock absorbers, if you've got them), 9 is the EBTCM (antilock brake and traction computer), and A is the DERM (air bag computer). These are cycled through one at a time, with dashes indicating the end of codes for that module. A "C" prefix means the code is currently active, meaning that the relevant parameters are out of range right now; an "H" means the code has been stored in history but is not currently active.
Unlike the car's other electronic systems, such as PCM, ABS, air bags, etc., there is no specific "CCM" lamp to indicate a malfunction when one is present. Instead, the CCM flashes the word "SYS" three times every once in a while on the LCD whenever there are active CCM codes present. If the code thrown is one that involves only the security system, the "SECURITY" lamp will illuminate instead, or they will both flash together if it involves the Fuel Enable Data Stream.
Upon entering diagnostic mode, as mentioned, you will first see a listing of diagnostic codes for each module. Afterwards, you will enter the menu (or you can press any information center buttons to skip to the menu). Did you know there was a menu? I didn't, until I read the FSM.
You'll know you're in the menu when you see the number "1.0". The first digit, before the decimal point, refers to which module you are talking to at the moment, as numbered above. The second digit indicates the menu item. Item .0 means that computer is awaiting instructions. Item .1 displays any codes for that module and .7 clears them. This applies to all of the car's computers/modules. Note that any non-CCM codes will always show up with the "H" as in history, since the CCM does not know whether or not they are currently active.
The CCM has additional options on top of these; .2 and .3 let you cycle through the CCM's stored data and inputs, respectively, and option .4 lets you toggle each of its outputs manually (this part is fun).
To navigate the menu items, use the "gauges" and "trip odo" button. To navigate to the next or previous module, hold down the "fuel" or "trip" button for a second. To select a menu item, press "ENG MET."
One thing that I recommend doing at this point, is see if you have any EBTCM codes stored (module 9 in '96), and then delete them. You will hear the brake pressure modulator valves near the EBTCM click as it resets, and you might suddenly feel that your brakes feel and work much better than before. This was the case for me; I had a lateral accelerometer code, as well as a code from back when my Opti died making the tachometer go crazy. Neither code has come back since I cleared them, meaning that the presence of codes alone was enough to severely effect how my brake functions.
Now for the fun part: The CCM data, input, and outputs. These are options .2, .3, and .4 in the CCM module menu, respectively. After selecting any of these, press "eng met" to go to the next value and "fuel info" to go to the previous. The selections are:
Display CCM Data (Mode 1.2):
01 - Fuel Level (Gallons, tenths)
02 - Dimming Potentiometer
03 - Ambient Light Sensor
04 - Rear Defogger Timer
05 - Vehicle Speed
06 - Pass-Key
07 - Ignition Voltage
08 - Switched Voltage
09 - Cluster dimming
10 - LCD backlight dimming
11 - Radio & Climate dimming
12 - LED dimming
13 & 14 - Vehicle configuration
15 - Oil monitor count
16 - CCM version
Display CCM input status (Mode 1.3):
1 - PassKey fuel
2 - English/metric status
3 - Door key switch
4 - Right Door ajar
5 - Left door ajar
6 - key in ignition but in "off" or "acc" position
7 - hatch ajar
8 - Power door unlock
9 - Power door lock
10 - Parking lights
11 - Rear defogger input (car must be running)
12 - Seat belt switch
13 - High beam switch
14 - Low oil level switch
These values are either "1" or "0," and when toggled, the new value will be appended on to the old value (01 means it was 0 but is now 1).
Cycle CCM Outputs (Mode 1.4):
Selecting these options will manually activate the lights and sounds the CCM produces.
1 - Change oil light
2 - Check gauges indicator
3 - Fasten seatbelt indicator
4 - Security lamp
5 - High beam indicator
6 & 7 - chimes
8 - LCD blanking
9 - Defogger relay
10 - Courtesy lamp
11 - Low oil lamp
12 - Theft relay
13 - DAB relay
14 - door ajar light
15 - Horns (This will actually beep the horns, watch out!)
So there you have it; you can now dazzle and impress your friends with your car's diagnostic features, as well as test any of the circuits and systems in the interior. Please correct any factual errors I have made in this post, and if you know of any information that would be useful to add to this thread, so as to make it a centralized source for information about the late model CCM, let me know.
10-16-2013, 01:31 PM
#60
Drifting
Thread Starter
It's crazy to notice this old guide I posted, back when I was relatively so new to cars and forums and explaining stuff, still getting google hits and replies! I'm still using the paperclip method pretty often whenever I've been messing with wiring and anything lights up on the dash. Lately I've had to hotwire my faulty ignition key switch / pellet sensor by sticking a resistor into the connector, and no matter where I am if I'm stranded, using the paperclip method I can tell it to output the key's resistance value it sees until I am sure the resistor is shoved in far enough to make contact.
I may not have mentioned enough in the tutorial about what you actually do to control the user interface / menu once you're in it. The buttons you press are the four information center ones: FUEL INFO, ENG MET, GAUGES, and TRIP/ODO. As soon as you start the car in paperclip mode, it will start outputting trouble codes one by one, but pressing any of those buttons skips to the menu. From there, the two buttons on the top row function sort of as forward / back buttons through the menu options (numbered like 1.0, 1.1, etc.) while the bottom two do forward / back navigation through the more specific sub-menus (like which particular CCM output to cycle if you're on option 1.4).
Deleting codes is option .7 of each module (so 1.7 if the CCM module is the one you want to delete codes for, i.e. to get rid of the flashing SYS until a code comes back. Or 4.7 for the PCM to turn the service engine light off, etc.).
Using the CCM as an example I think what you'd do is select 1.7 using the top row buttons and then use the bottom row buttons to actually do the deleting.
I may not have mentioned enough in the tutorial about what you actually do to control the user interface / menu once you're in it. The buttons you press are the four information center ones: FUEL INFO, ENG MET, GAUGES, and TRIP/ODO. As soon as you start the car in paperclip mode, it will start outputting trouble codes one by one, but pressing any of those buttons skips to the menu. From there, the two buttons on the top row function sort of as forward / back buttons through the menu options (numbered like 1.0, 1.1, etc.) while the bottom two do forward / back navigation through the more specific sub-menus (like which particular CCM output to cycle if you're on option 1.4).
Deleting codes is option .7 of each module (so 1.7 if the CCM module is the one you want to delete codes for, i.e. to get rid of the flashing SYS until a code comes back. Or 4.7 for the PCM to turn the service engine light off, etc.).
Using the CCM as an example I think what you'd do is select 1.7 using the top row buttons and then use the bottom row buttons to actually do the deleting.
Last edited by LouisvilleLT4; 01-21-2014 at 03:11 PM.
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