C68 Air conditioning problem (pics inside)
01-21-2005, 05:28 PM
#1
Melting Slicks
Thread Starter
C68 Air conditioning problem (pics inside)
My C68 automatic climate control do not works.
Reading the forum I see that a common problem can be the Programmer (the one under the dash just above the gas pedal under a black box).
It's really a pain to reach it...
in the first image the programmer.
where there is the black arrow there is a pluf with few little blades that is not connected with nothing!
Someone know if this connector should be connected with something?
in the third pic you can see a view of the under the dash
I noticed (where I added a 2 and a 3) that there is a box support that allow two black boxes.
I have only one! (2) the 3 is missing! Someone know the function of these (this ) boxes (box)
Thanks
-Beppe-
Reading the forum I see that a common problem can be the Programmer (the one under the dash just above the gas pedal under a black box).
It's really a pain to reach it...
in the first image the programmer.
where there is the black arrow there is a pluf with few little blades that is not connected with nothing!
Someone know if this connector should be connected with something?
in the third pic you can see a view of the under the dash
I noticed (where I added a 2 and a 3) that there is a box support that allow two black boxes.
I have only one! (2) the 3 is missing! Someone know the function of these (this ) boxes (box)
Thanks
-Beppe-
01-21-2005, 06:12 PM
#2
Team Owner
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If you just opened up the controller and there was no connection to those jumpers then there should be none. Perhaps that same PCB was used in several different applications, one of which may have needed those pins.
I've not been under the dash much (yet) so can't give a clue on that black box.
I've not been under the dash much (yet) so can't give a clue on that black box.
01-21-2005, 07:07 PM
#3
Team Owner
those are relays...
I am just not sure what they do. I don't have a book for 1990's.
As for the climate control problem... you need to be sure the system is getting vacuum.
Questions:
1) Does ANYTHING happen when you push the various buttons on the climate control?
2) Do you hear the compressor fire?
3) Have you tested for AC codes?
I am just not sure what they do. I don't have a book for 1990's.
As for the climate control problem... you need to be sure the system is getting vacuum.
Questions:
1) Does ANYTHING happen when you push the various buttons on the climate control?
2) Do you hear the compressor fire?
3) Have you tested for AC codes?
01-21-2005, 07:57 PM
#4
Melting Slicks
Member Since: Aug 1999
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The Relay in the picture is the Bose Relay. It provides 12 volts to the Bose amps.
The socket with no Relay installed, is used only on ZR1's for the 2nd Fuel Pump.
The socket with no Relay installed, is used only on ZR1's for the 2nd Fuel Pump.
01-22-2005, 05:32 AM
#5
Melting Slicks
Thread Starter
Originally Posted by bogus
those are relays...
I am just not sure what they do. I don't have a book for 1990's.
As for the climate control problem... you need to be sure the system is getting vacuum.
Questions:
1) Does ANYTHING happen when you push the various buttons on the climate control?
2) Do you hear the compressor fire?
3) Have you tested for AC codes?
I am just not sure what they do. I don't have a book for 1990's.
As for the climate control problem... you need to be sure the system is getting vacuum.
Questions:
1) Does ANYTHING happen when you push the various buttons on the climate control?
2) Do you hear the compressor fire?
3) Have you tested for AC codes?
(I changed 2 control unit and both works the same ) in the display I have always " - --"
2) No, the system is dry (no refrigerant on it)
3) I tried. If I push the two arrow for 5 secs the "- --" condition becomes " -00 " if I push the up arrow it change numbers (from 00 to 37" but when I push the central fan button to see codes NOthing happens.
Thanks foe your further help
-Beppe-
01-22-2005, 03:36 PM
#6
Melting Slicks
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"---" indicates a E & C bus failure between the Programmer and the Heater/AC Control Head.
(Not communicating).
The Programmer gets power from the CTSY and A/C fuse.
Since you have power at the Control Head, the A/C fuse must be good.
If your interior courtesy lights are working, the CTSY fuse must be good.
The Bose Radio Control Head is also on this bus so it could cause a problem on the E&C bus. (NOT LIKELY).
You could disconnect the cables from the back of the Radio Control Head to eliminate it.
Your pictures look like some of the connectors have corrosion on them. Clean all of the connectors with electrical contact cleaner and hook them back up and re-test.
If it still doesn't work the only thing you can do is verify the voltage on the E&C bus to see if it's shorted to B+ (12 Volts) or shorted to ground. (Zero volts).
If you have a scope, you can monitor this bus for any activity while you press different buttons.
On the ALDL Connector above the drivers right knee the connector looks like this.
FEDCBA
GHJKLM
With a Volt meter, measure between pin J (E&C bus) and pin A (Ground). Should measure around 9.2 volts DC. (Doesn't matter if ignition is on or off).
If it measures OK, the Programmer is probably bad.
If you had a Tech 1 you could attach it to the Diagnostic connector and simulate the Heater/AC control head to isolate the problem.
(Not communicating).
The Programmer gets power from the CTSY and A/C fuse.
Since you have power at the Control Head, the A/C fuse must be good.
If your interior courtesy lights are working, the CTSY fuse must be good.
The Bose Radio Control Head is also on this bus so it could cause a problem on the E&C bus. (NOT LIKELY).
You could disconnect the cables from the back of the Radio Control Head to eliminate it.
Your pictures look like some of the connectors have corrosion on them. Clean all of the connectors with electrical contact cleaner and hook them back up and re-test.
If it still doesn't work the only thing you can do is verify the voltage on the E&C bus to see if it's shorted to B+ (12 Volts) or shorted to ground. (Zero volts).
If you have a scope, you can monitor this bus for any activity while you press different buttons.
On the ALDL Connector above the drivers right knee the connector looks like this.
FEDCBA
GHJKLM
With a Volt meter, measure between pin J (E&C bus) and pin A (Ground). Should measure around 9.2 volts DC. (Doesn't matter if ignition is on or off).
If it measures OK, the Programmer is probably bad.
If you had a Tech 1 you could attach it to the Diagnostic connector and simulate the Heater/AC control head to isolate the problem.
Last edited by Hooked on Vettes; 01-22-2005 at 03:47 PM.
01-23-2005, 05:47 AM
#7
Melting Slicks
Thread Starter
Originally Posted by Hooked on Vettes
"---" indicates a E & C bus failure between the Programmer and the Heater/AC Control Head.
(Not communicating).
The Programmer gets power from the CTSY and A/C fuse.
Since you have power at the Control Head, the A/C fuse must be good.
If your interior courtesy lights are working, the CTSY fuse must be good.
The Bose Radio Control Head is also on this bus so it could cause a problem on the E&C bus. (NOT LIKELY).
You could disconnect the cables from the back of the Radio Control Head to eliminate it.
Your pictures look like some of the connectors have corrosion on them. Clean all of the connectors with electrical contact cleaner and hook them back up and re-test.
If it still doesn't work the only thing you can do is verify the voltage on the E&C bus to see if it's shorted to B+ (12 Volts) or shorted to ground. (Zero volts).
If you have a scope, you can monitor this bus for any activity while you press different buttons.
On the ALDL Connector above the drivers right knee the connector looks like this.
FEDCBA
GHJKLM
With a Volt meter, measure between pin J (E&C bus) and pin A (Ground). Should measure around 9.2 volts DC. (Doesn't matter if ignition is on or off).
If it measures OK, the Programmer is probably bad.
If you had a Tech 1 you could attach it to the Diagnostic connector and simulate the Heater/AC control head to isolate the problem.
(Not communicating).
The Programmer gets power from the CTSY and A/C fuse.
Since you have power at the Control Head, the A/C fuse must be good.
If your interior courtesy lights are working, the CTSY fuse must be good.
The Bose Radio Control Head is also on this bus so it could cause a problem on the E&C bus. (NOT LIKELY).
You could disconnect the cables from the back of the Radio Control Head to eliminate it.
Your pictures look like some of the connectors have corrosion on them. Clean all of the connectors with electrical contact cleaner and hook them back up and re-test.
If it still doesn't work the only thing you can do is verify the voltage on the E&C bus to see if it's shorted to B+ (12 Volts) or shorted to ground. (Zero volts).
If you have a scope, you can monitor this bus for any activity while you press different buttons.
On the ALDL Connector above the drivers right knee the connector looks like this.
FEDCBA
GHJKLM
With a Volt meter, measure between pin J (E&C bus) and pin A (Ground). Should measure around 9.2 volts DC. (Doesn't matter if ignition is on or off).
If it measures OK, the Programmer is probably bad.
If you had a Tech 1 you could attach it to the Diagnostic connector and simulate the Heater/AC control head to isolate the problem.
...I will try and I let you know!
Thanks again
.
Where do you take these informations? On the service manual??
-Beppe-
01-24-2005, 04:56 PM
#8
Melting Slicks
Thread Starter
I measured the voltage between the pin J and the ground A at the ALDL connector.
I read about 14 V !! (It not measures 9,2V...)
What this means? I means that the programmer is OK and the Bus is shorted to B+?
What I have to do if my analysys is good?
About the radio.
Yes I have a custom Sony radio installed, but even when I was WITHOUT radio the AC was NOT working too.
Another thing I missed to say is that when I turn the key to ON position the fAN OF THE BLOWER starts at a medium speed and I have no way to correct the speed with the control head unit because the there is not effect pushing any buttons. The only way I have to stop the fan is to disconnect the connector at the blower.
I need again help, thanks
-Beppe-
I read about 14 V !! (It not measures 9,2V...)
What this means? I means that the programmer is OK and the Bus is shorted to B+?
What I have to do if my analysys is good?
About the radio.
Yes I have a custom Sony radio installed, but even when I was WITHOUT radio the AC was NOT working too.
Another thing I missed to say is that when I turn the key to ON position the fAN OF THE BLOWER starts at a medium speed and I have no way to correct the speed with the control head unit because the there is not effect pushing any buttons. The only way I have to stop the fan is to disconnect the connector at the blower.
I need again help, thanks
-Beppe-
01-24-2005, 05:52 PM
#9
Melting Slicks
Member Since: Aug 1999
Location: Baltimore, MD USA
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With the ignition on (engine not running) you measure 14 volts from A to J?
I don't see how you can measure 14 volts on A to J when the voltage source which is the battery can't be more than around 12.7 VDC with the engine not running.
Since you have an after market radio, that eliminates it from causing your problem.
With the Control Head plugged in, disconnect the electrical connectors from the Programmer and re-check A to J. If it now reads around 9.2 VDC, the Programmer is bad.
I don't see how you can measure 14 volts on A to J when the voltage source which is the battery can't be more than around 12.7 VDC with the engine not running.
Since you have an after market radio, that eliminates it from causing your problem.
With the Control Head plugged in, disconnect the electrical connectors from the Programmer and re-check A to J. If it now reads around 9.2 VDC, the Programmer is bad.
Last edited by Hooked on Vettes; 01-24-2005 at 05:58 PM.
01-25-2005, 03:18 PM
#10
Melting Slicks
Thread Starter
Originally Posted by Hooked on Vettes
With the ignition on (engine not running) you measure 14 volts from A to J?
I don't see how you can measure 14 volts on A to J when the voltage source which is the battery can't be more than around 12.7 VDC with the engine not running.
Since you have an after market radio, that eliminates it from causing your problem.
With the Control Head plugged in, disconnect the electrical connectors from the Programmer and re-check A to J. If it now reads around 9.2 VDC, the Programmer is bad.
I don't see how you can measure 14 volts on A to J when the voltage source which is the battery can't be more than around 12.7 VDC with the engine not running.
Since you have an after market radio, that eliminates it from causing your problem.
With the Control Head plugged in, disconnect the electrical connectors from the Programmer and re-check A to J. If it now reads around 9.2 VDC, the Programmer is bad.
Now I performed a right read:
Programmer connected
Key in OFF position
Reading from A to J: 4.0 V
Programmer connected
Key in ON position (engine not started)
Reading from A to J: 5.8V
Programmer disconnected
Key in OFF position
Reading from A to J: the slim arrowof the multimeter do not move at all
Programmer disconnected
Key in ON position (engine not started)
Reading from A to J: 4.6 volts
With the programmer connected if i push some of the Control unit buttons the arrow in the multimeter seems to have a vibration.
Just to see if I made a right reading I tried directly on the battery and i had a value of 11.9
Thanks for your help
-Beppe-
01-26-2005, 05:00 PM
#12
Melting Slicks
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All I can tell you is I measured around 9 volts DC from A to J with the key in run or off.
I've looked at the signal with an oscilloscope and with no buttons pushed the signal level is 9.2 volts DC.
When I press a button on the Heater/AC Control Head, there is a low frequency square wave for about .5 seconds then the signal goes back to 9.2 volts DC.
This square wave must be the data being sent between the Control Head and the Programmer.
Normally when you turn the key to on, the Heater/AC Control Head displays the outside temperature by default. Since you only see "---" my guess is the Programmer is bad.
The Helms manual only shows a block diagram of the Programmer and no component schematics so it's impossible to tell what the circuits inside the Programmer looks like.
I've looked at the signal with an oscilloscope and with no buttons pushed the signal level is 9.2 volts DC.
When I press a button on the Heater/AC Control Head, there is a low frequency square wave for about .5 seconds then the signal goes back to 9.2 volts DC.
This square wave must be the data being sent between the Control Head and the Programmer.
Normally when you turn the key to on, the Heater/AC Control Head displays the outside temperature by default. Since you only see "---" my guess is the Programmer is bad.
The Helms manual only shows a block diagram of the Programmer and no component schematics so it's impossible to tell what the circuits inside the Programmer looks like.
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