how do you pull codes?
#2
Le Mans Master
Member Since: Sep 2003
Location: Littleton CO
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1996 used OBDII, and the Powertrain Control Module (PCM) codes cannot be displayed on the dash, even though the service manual gives the procedure. You'll need to buy a code reader to get them, or most auto parts stores will have one to help customers out. Central Control Module (CCM) codes can be displayed on the dash using the FSM procedure.
See below where I have quoted a couple of my own posts on the topic. The first one has a link which shows the procedure to get CCM codes.
See below where I have quoted a couple of my own posts on the topic. The first one has a link which shows the procedure to get CCM codes.
"SYS" indicates that one or more codes has been set in the CCM. It simply seems that weak batteries and aftermarket radios (they disturb the dimming circuit - mine does this but I haven't bothered to do the fix) are the most common cause that people post about.
To be thorough, check codes as shown here: http://www.corvettebuyers.com/c4vettes/codes.htm
You'll need to scroll to the end to find the correct ALDL pins to jump for '96. If my understanding is correct, any codes that will flash "SYS" can be seen this way, but you must keep in mind that '96 is OBDII and that this method does not access the PCM codes (these set the check engine light) as suggested by that site.
***CLIFF'S NOTES: Your battery may be old, but not necessarily bad. See what the code is first.***
To be thorough, check codes as shown here: http://www.corvettebuyers.com/c4vettes/codes.htm
You'll need to scroll to the end to find the correct ALDL pins to jump for '96. If my understanding is correct, any codes that will flash "SYS" can be seen this way, but you must keep in mind that '96 is OBDII and that this method does not access the PCM codes (these set the check engine light) as suggested by that site.
***CLIFF'S NOTES: Your battery may be old, but not necessarily bad. See what the code is first.***
Are you sure? Looking in my service manual, stored codes for CCM monitored systems are what the message means.
How did you check for codes? My OBDII code reader seems to only retrieve PCM codes, for which the check engine light is lit. For some reason, I can't see the CCM codes with it, even though they are present (aftermarket radio is my malfunction) and can be displayed on the dash using the paperclip jumper method.
If you had someone like Autozone check codes, they probably used a similar code reader which might behave the same way. I'd suggest that another look is in order using another code reader and/or the on-board functionality.
** Keep in mind that PCM codes cannot be displayed on the dash for the '96 OBDII cars, contrary to that part of the service manual.
How did you check for codes? My OBDII code reader seems to only retrieve PCM codes, for which the check engine light is lit. For some reason, I can't see the CCM codes with it, even though they are present (aftermarket radio is my malfunction) and can be displayed on the dash using the paperclip jumper method.
If you had someone like Autozone check codes, they probably used a similar code reader which might behave the same way. I'd suggest that another look is in order using another code reader and/or the on-board functionality.
** Keep in mind that PCM codes cannot be displayed on the dash for the '96 OBDII cars, contrary to that part of the service manual.
#3
Team Owner
Just picked up a code reader at Advance Auto Parts yesterday.
Best $80.00 investment I've made to date. My local mechanic charges $90.00 to diagnose ODBII codes. ('95 and newer vehicles)
If I need to use it again, it's paid for itself in diagnosis fees alone.
(P.S., order it on-line, pick it up at the local store 1 hour later, and get $5.00 off the price)
here's a link (Because I'm such a nice guy)
http://www.partsamerica.com/ProductD...tnumber=CP9125
Best $80.00 investment I've made to date. My local mechanic charges $90.00 to diagnose ODBII codes. ('95 and newer vehicles)
If I need to use it again, it's paid for itself in diagnosis fees alone.
(P.S., order it on-line, pick it up at the local store 1 hour later, and get $5.00 off the price)
here's a link (Because I'm such a nice guy)
http://www.partsamerica.com/ProductD...tnumber=CP9125
#4
Le Mans Master
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#5
Le Mans Master
Paper clip from pin 12 to ground (4 or 5 are both ground)
On a 94-96 you can check the codes with a paper clip as follows:
You short pin "12" to pin "4" and turn the ignition switch to "On" without starting the engine.
The speedometer will display any codes using the same protocol as the 1990-1993 model but there are some changes in the designation for the modules plus additional modules are added:
Module "1" is still the CCM module.
Module "4" is now called the PCM module (Powertrain Control Module) because automatic transmission computer control was added to Engine Control Module in 1994.
Module 7 (on the 1996 model only) is the RTD module. (This is the Real Time Dampening module which replaced the Selective Ride Control module in 1996).
Module 9 is the ABS/ASR module number from 1994 through 1996.
Finally, Module "A", the DERM (Dynamic Energy Control Module --- (the air bag control module) will be requested to show any codes.
Just like the 1990-1993 display, you read the codes on the speedometer (big) and read the module number on the trip odometer (small).
A series of dashed lines for instance “ - - -“ indicates no more stored codes for that module.
A code showing as “C12” for the CCM module (module #1) means no codes are stored. So C12 is a good thing to see.
Again, you can cause the codes to repeat by turning the ignition off for five seconds and then back on.
Turn the ignition off and remove the short to restore normal operation.
To clear the codes,
1. With ignition "off" ground terminal #12 of the DLC (use bent paper clip to connect pin 4 to pin 12)
2. Turn ignition "on".
3. Press trip/odo button on the DIC until 1.7 appears in the trip
monitor area of the instrument cluster.
4. Press eng/met button on the DIC & hold until "---" appears in the
speedometer area of the cluster, this will clear CCM DTC'S.
To clear PCM/ECM codes do the following:
1. Press the trip reset button on the DIC until the desired system is displayed. In this case it will be 4.0.
2. Press trip/odo button on the DIC until the desired diagnostic mode(4.7) is displayed on the trip monitor area of the cluster.
3. Press & hold the eng/met button on the DIC until "---" is
displayed in the speedometer area of the cluster, this will clear PCM codes.
To clear ABS/ASR codes do the following:
Same as above but you’re looking for “9.7” on the trip odo
And here are the codes
1994-1995: Diagnostic Trouble Codes
DTC #11: Malfunction Indicator Lamp Circuit.
DTC #13: Bank #1 Heated Oxygen Sensor #1 Circuit:
DTC #14: Engine Coolant Temperature Sensor Circuit Voltage Low.
DTC #15: Engine Coolant Temperature Sensor Circuit Voltage High.
DTC #16: Distributor Ignition System Low Pulse.
DTC #18: Injector Circuit.
DTC #21: Throttle Position Sensor Circuit Voltage High.
DTC #22: Throttle Position Sensor Circuit Voltage Low.
DTC #23: Intake Temperature Sensor Circuit Voltage High.
DTC #24: Vehicle Speed Sensor Circuit.
DTC #25: Intake Air Temperature Sensor Circuit Voltage Low.
DTC #26: Evaporative Emission Canister Purge Solenoid Valve Circuit.
DTC #27: EGR Vacuum Control Signal Solenoid Valve Circuit.
DTC #28: Transmission Range Pressure Switch Assembly Fault.
DTC #29: Secondary Air Injection Pump Circuit.
DTC #32: Exhaust Gas Recalculation.
DTC #33: Manifold Absolute Pressure Sensor Circuit High.
DTC #34: Manifold Absolute Pressure Sensor Circuit Low.
DTC #36: Distributor Ignition System High Pulse.
DTC #37: Brake Switch Stuck On.
DTC #38: Brake Switch Stuck Off.
DTC #41: Ignition Control Circuit Open.
DTC #42: Ignition Control Circuit Shorted.
DTC #43: Knock Sensor Circuit.
DTC #44: Bank 1 LF Heated Oxygen Sensor #1 Circuit Lean.
DTC #45: Bank 1 LF Heated Oxygen Sensor #1 Circuit Rich.
DTC #47: Knock Sensor Circuit Or Module Missing.
DTC #48: Mass Air Flow Sensor Circuit.
DTC #50: System Voltage Low.
DTC #51: EPROM Programming Error.
DTC #52: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #53: System Voltage Low.
DTC #55: Fuel Lean Monitor.
DTC #58: Transmission Fluid Temperature Sensor Circuit Low.
DTC #59: Transmission Fluid Temperature Sensor Circuit High.
DTC #62: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #63: Bank 2 RF Heated Oxygen Sensor #1 Circuit Open.
DTC #64: Bank 2 RF Heated Oxygen Sensor #1 Circuit Lean.
DTC #65: Bank 2 RF Heated Oxygen Sensor #1 Circuit Rich.
DTC #66: A/C Refrigerant Pressure Sensor Circuit Open.
DTC #67: A/C Pressure Sensor Circuit Sensor or A/C Clutch.
DTC #68: A/C Relay Circuit.
DTC #69: A /C Clutch Circuit.
DTC #70: A/C Clutch Relay Driver Circuit.
DTC #72: Vehicle Speed Sensor Loss.
DTC #73: Pressure Control Solenoid Circuit Current Error.
DTC #74: Traction Control System Circuit Low.
DTC #75: Transmission System Voltage Low
DTC #77: Primary Cooling Fan Relay Control Circuit.
DTC #78: Secondary Cooling Fan Relay Control Circuit.
DTC #79: Transmission Fluid Overtemp.
DTC #80: Transmission Component Slipping.
DTC #81: Transmission 2-3 Shift Solenoid Circuit.
DTC #82: Transmission 1-2 Shift Solenoid Circuit.
DTC #83: Torque Converter Solenoid Voltage High.
DTC #84: 3-2 Control Solenoid Circuit.(Auto Only).
DTC #84: 2nd And 3rd Gear Blockout Relay Control Circuit.
DTC #85: Transmission TCC Stock On.
DTC #90: Transmission TCC Solenoid Circuit.
DTC #91: One To Four Upshift Lamp(Manual Only).
DTC #97: VSS Output Circuit.
DTC #98: Tachometer Output Signal Voltage Wrong.
To run a diagnostic on the PKE system, connect pins 4 and 8 on the ALDL (see pic below to see pin label order)
And the PKE diagnostic system works as follows:
With pins 4 and 8 connected, the PKE light in the Driver Info Centre will flash the codes.
Here is the list of DTCs and what they mean:
DTC #12: Receiver Memory Bad
DTC #13: Transmitter Not in Range
DTC #14: Non-Valid Transmitter Received
DTC #15: Valid Transmitter Received
DTC #16: Passenger Door Button Depressed
DTC #17: Hatch Button Depressed
95s are NOT OBD2.
On a 94-96 you can check the codes with a paper clip as follows:
You short pin "12" to pin "4" and turn the ignition switch to "On" without starting the engine.
The speedometer will display any codes using the same protocol as the 1990-1993 model but there are some changes in the designation for the modules plus additional modules are added:
Module "1" is still the CCM module.
Module "4" is now called the PCM module (Powertrain Control Module) because automatic transmission computer control was added to Engine Control Module in 1994.
Module 7 (on the 1996 model only) is the RTD module. (This is the Real Time Dampening module which replaced the Selective Ride Control module in 1996).
Module 9 is the ABS/ASR module number from 1994 through 1996.
Finally, Module "A", the DERM (Dynamic Energy Control Module --- (the air bag control module) will be requested to show any codes.
Just like the 1990-1993 display, you read the codes on the speedometer (big) and read the module number on the trip odometer (small).
A series of dashed lines for instance “ - - -“ indicates no more stored codes for that module.
A code showing as “C12” for the CCM module (module #1) means no codes are stored. So C12 is a good thing to see.
Again, you can cause the codes to repeat by turning the ignition off for five seconds and then back on.
Turn the ignition off and remove the short to restore normal operation.
To clear the codes,
1. With ignition "off" ground terminal #12 of the DLC (use bent paper clip to connect pin 4 to pin 12)
2. Turn ignition "on".
3. Press trip/odo button on the DIC until 1.7 appears in the trip
monitor area of the instrument cluster.
4. Press eng/met button on the DIC & hold until "---" appears in the
speedometer area of the cluster, this will clear CCM DTC'S.
To clear PCM/ECM codes do the following:
1. Press the trip reset button on the DIC until the desired system is displayed. In this case it will be 4.0.
2. Press trip/odo button on the DIC until the desired diagnostic mode(4.7) is displayed on the trip monitor area of the cluster.
3. Press & hold the eng/met button on the DIC until "---" is
displayed in the speedometer area of the cluster, this will clear PCM codes.
To clear ABS/ASR codes do the following:
Same as above but you’re looking for “9.7” on the trip odo
And here are the codes
1994-1995: Diagnostic Trouble Codes
DTC #11: Malfunction Indicator Lamp Circuit.
DTC #13: Bank #1 Heated Oxygen Sensor #1 Circuit:
DTC #14: Engine Coolant Temperature Sensor Circuit Voltage Low.
DTC #15: Engine Coolant Temperature Sensor Circuit Voltage High.
DTC #16: Distributor Ignition System Low Pulse.
DTC #18: Injector Circuit.
DTC #21: Throttle Position Sensor Circuit Voltage High.
DTC #22: Throttle Position Sensor Circuit Voltage Low.
DTC #23: Intake Temperature Sensor Circuit Voltage High.
DTC #24: Vehicle Speed Sensor Circuit.
DTC #25: Intake Air Temperature Sensor Circuit Voltage Low.
DTC #26: Evaporative Emission Canister Purge Solenoid Valve Circuit.
DTC #27: EGR Vacuum Control Signal Solenoid Valve Circuit.
DTC #28: Transmission Range Pressure Switch Assembly Fault.
DTC #29: Secondary Air Injection Pump Circuit.
DTC #32: Exhaust Gas Recalculation.
DTC #33: Manifold Absolute Pressure Sensor Circuit High.
DTC #34: Manifold Absolute Pressure Sensor Circuit Low.
DTC #36: Distributor Ignition System High Pulse.
DTC #37: Brake Switch Stuck On.
DTC #38: Brake Switch Stuck Off.
DTC #41: Ignition Control Circuit Open.
DTC #42: Ignition Control Circuit Shorted.
DTC #43: Knock Sensor Circuit.
DTC #44: Bank 1 LF Heated Oxygen Sensor #1 Circuit Lean.
DTC #45: Bank 1 LF Heated Oxygen Sensor #1 Circuit Rich.
DTC #47: Knock Sensor Circuit Or Module Missing.
DTC #48: Mass Air Flow Sensor Circuit.
DTC #50: System Voltage Low.
DTC #51: EPROM Programming Error.
DTC #52: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #53: System Voltage Low.
DTC #55: Fuel Lean Monitor.
DTC #58: Transmission Fluid Temperature Sensor Circuit Low.
DTC #59: Transmission Fluid Temperature Sensor Circuit High.
DTC #62: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #63: Bank 2 RF Heated Oxygen Sensor #1 Circuit Open.
DTC #64: Bank 2 RF Heated Oxygen Sensor #1 Circuit Lean.
DTC #65: Bank 2 RF Heated Oxygen Sensor #1 Circuit Rich.
DTC #66: A/C Refrigerant Pressure Sensor Circuit Open.
DTC #67: A/C Pressure Sensor Circuit Sensor or A/C Clutch.
DTC #68: A/C Relay Circuit.
DTC #69: A /C Clutch Circuit.
DTC #70: A/C Clutch Relay Driver Circuit.
DTC #72: Vehicle Speed Sensor Loss.
DTC #73: Pressure Control Solenoid Circuit Current Error.
DTC #74: Traction Control System Circuit Low.
DTC #75: Transmission System Voltage Low
DTC #77: Primary Cooling Fan Relay Control Circuit.
DTC #78: Secondary Cooling Fan Relay Control Circuit.
DTC #79: Transmission Fluid Overtemp.
DTC #80: Transmission Component Slipping.
DTC #81: Transmission 2-3 Shift Solenoid Circuit.
DTC #82: Transmission 1-2 Shift Solenoid Circuit.
DTC #83: Torque Converter Solenoid Voltage High.
DTC #84: 3-2 Control Solenoid Circuit.(Auto Only).
DTC #84: 2nd And 3rd Gear Blockout Relay Control Circuit.
DTC #85: Transmission TCC Stock On.
DTC #90: Transmission TCC Solenoid Circuit.
DTC #91: One To Four Upshift Lamp(Manual Only).
DTC #97: VSS Output Circuit.
DTC #98: Tachometer Output Signal Voltage Wrong.
To run a diagnostic on the PKE system, connect pins 4 and 8 on the ALDL (see pic below to see pin label order)
And the PKE diagnostic system works as follows:
With pins 4 and 8 connected, the PKE light in the Driver Info Centre will flash the codes.
Here is the list of DTCs and what they mean:
DTC #12: Receiver Memory Bad
DTC #13: Transmitter Not in Range
DTC #14: Non-Valid Transmitter Received
DTC #15: Valid Transmitter Received
DTC #16: Passenger Door Button Depressed
DTC #17: Hatch Button Depressed
Last edited by Casethecorvetteman; 10-06-2007 at 10:04 AM.
#6
Burning Brakes
great info...thanks as I am a new C4 owner!
I have a question:
If I have a 99 Tahoe, a 05 Bonneville, and a 95 Vette...I need this scanner to read all 3 cars correct?
http://www.partsamerica.com/ProductD...artNumber=2000
Is there anything else out there that anyone recommends thats decent to read any car from 82 on? I really only need GM...but might not be a bad idea to have one to read all cars.
Don't want to spend a fortune on one either...
And whats 29 frame capture mean on some of the higher end units?
Thanks guys
I have a question:
If I have a 99 Tahoe, a 05 Bonneville, and a 95 Vette...I need this scanner to read all 3 cars correct?
http://www.partsamerica.com/ProductD...artNumber=2000
Is there anything else out there that anyone recommends thats decent to read any car from 82 on? I really only need GM...but might not be a bad idea to have one to read all cars.
Don't want to spend a fortune on one either...
And whats 29 frame capture mean on some of the higher end units?
Thanks guys
#7
Intermediate
Member Since: Nov 2007
Location: Bay Area CA
Posts: 34
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Paper clip from pin 12 to ground (4 or 5 are both ground)
On a 94-96 you can check the codes with a paper clip as follows:
You short pin "12" to pin "4" and turn the ignition switch to "On" without starting the engine.
The speedometer will display any codes using the same protocol as the 1990-1993 model but there are some changes in the designation for the modules plus additional modules are added:
Module "1" is still the CCM module.
Module "4" is now called the PCM module (Powertrain Control Module) because automatic transmission computer control was added to Engine Control Module in 1994.
Module 7 (on the 1996 model only) is the RTD module. (This is the Real Time Dampening module which replaced the Selective Ride Control module in 1996).
Module 9 is the ABS/ASR module number from 1994 through 1996.
Finally, Module "A", the DERM (Dynamic Energy Control Module --- (the air bag control module) will be requested to show any codes.
Just like the 1990-1993 display, you read the codes on the speedometer (big) and read the module number on the trip odometer (small).
A series of dashed lines for instance “ - - -“ indicates no more stored codes for that module.
A code showing as “C12” for the CCM module (module #1) means no codes are stored. So C12 is a good thing to see.
Again, you can cause the codes to repeat by turning the ignition off for five seconds and then back on.
Turn the ignition off and remove the short to restore normal operation.
To clear the codes,
1. With ignition "off" ground terminal #12 of the DLC (use bent paper clip to connect pin 4 to pin 12)
2. Turn ignition "on".
3. Press trip/odo button on the DIC until 1.7 appears in the trip
monitor area of the instrument cluster.
4. Press eng/met button on the DIC & hold until "---" appears in the
speedometer area of the cluster, this will clear CCM DTC'S.
To clear PCM/ECM codes do the following:
1. Press the trip reset button on the DIC until the desired system is displayed. In this case it will be 4.0.
2. Press trip/odo button on the DIC until the desired diagnostic mode(4.7) is displayed on the trip monitor area of the cluster.
3. Press & hold the eng/met button on the DIC until "---" is
displayed in the speedometer area of the cluster, this will clear PCM codes.
To clear ABS/ASR codes do the following:
Same as above but you’re looking for “9.7” on the trip odo
And here are the codes
1994-1995: Diagnostic Trouble Codes
DTC #11: Malfunction Indicator Lamp Circuit.
DTC #13: Bank #1 Heated Oxygen Sensor #1 Circuit:
DTC #14: Engine Coolant Temperature Sensor Circuit Voltage Low.
DTC #15: Engine Coolant Temperature Sensor Circuit Voltage High.
DTC #16: Distributor Ignition System Low Pulse.
DTC #18: Injector Circuit.
DTC #21: Throttle Position Sensor Circuit Voltage High.
DTC #22: Throttle Position Sensor Circuit Voltage Low.
DTC #23: Intake Temperature Sensor Circuit Voltage High.
DTC #24: Vehicle Speed Sensor Circuit.
DTC #25: Intake Air Temperature Sensor Circuit Voltage Low.
DTC #26: Evaporative Emission Canister Purge Solenoid Valve Circuit.
DTC #27: EGR Vacuum Control Signal Solenoid Valve Circuit.
DTC #28: Transmission Range Pressure Switch Assembly Fault.
DTC #29: Secondary Air Injection Pump Circuit.
DTC #32: Exhaust Gas Recalculation.
DTC #33: Manifold Absolute Pressure Sensor Circuit High.
DTC #34: Manifold Absolute Pressure Sensor Circuit Low.
DTC #36: Distributor Ignition System High Pulse.
DTC #37: Brake Switch Stuck On.
DTC #38: Brake Switch Stuck Off.
DTC #41: Ignition Control Circuit Open.
DTC #42: Ignition Control Circuit Shorted.
DTC #43: Knock Sensor Circuit.
DTC #44: Bank 1 LF Heated Oxygen Sensor #1 Circuit Lean.
DTC #45: Bank 1 LF Heated Oxygen Sensor #1 Circuit Rich.
DTC #47: Knock Sensor Circuit Or Module Missing.
DTC #48: Mass Air Flow Sensor Circuit.
DTC #50: System Voltage Low.
DTC #51: EPROM Programming Error.
DTC #52: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #53: System Voltage Low.
DTC #55: Fuel Lean Monitor.
DTC #58: Transmission Fluid Temperature Sensor Circuit Low.
DTC #59: Transmission Fluid Temperature Sensor Circuit High.
DTC #62: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #63: Bank 2 RF Heated Oxygen Sensor #1 Circuit Open.
DTC #64: Bank 2 RF Heated Oxygen Sensor #1 Circuit Lean.
DTC #65: Bank 2 RF Heated Oxygen Sensor #1 Circuit Rich.
DTC #66: A/C Refrigerant Pressure Sensor Circuit Open.
DTC #67: A/C Pressure Sensor Circuit Sensor or A/C Clutch.
DTC #68: A/C Relay Circuit.
DTC #69: A /C Clutch Circuit.
DTC #70: A/C Clutch Relay Driver Circuit.
DTC #72: Vehicle Speed Sensor Loss.
DTC #73: Pressure Control Solenoid Circuit Current Error.
DTC #74: Traction Control System Circuit Low.
DTC #75: Transmission System Voltage Low
DTC #77: Primary Cooling Fan Relay Control Circuit.
DTC #78: Secondary Cooling Fan Relay Control Circuit.
DTC #79: Transmission Fluid Overtemp.
DTC #80: Transmission Component Slipping.
DTC #81: Transmission 2-3 Shift Solenoid Circuit.
DTC #82: Transmission 1-2 Shift Solenoid Circuit.
DTC #83: Torque Converter Solenoid Voltage High.
DTC #84: 3-2 Control Solenoid Circuit.(Auto Only).
DTC #84: 2nd And 3rd Gear Blockout Relay Control Circuit.
DTC #85: Transmission TCC Stock On.
DTC #90: Transmission TCC Solenoid Circuit.
DTC #91: One To Four Upshift Lamp(Manual Only).
DTC #97: VSS Output Circuit.
DTC #98: Tachometer Output Signal Voltage Wrong.
To run a diagnostic on the PKE system, connect pins 4 and 8 on the ALDL (see pic below to see pin label order)
And the PKE diagnostic system works as follows:
With pins 4 and 8 connected, the PKE light in the Driver Info Centre will flash the codes.
Here is the list of DTCs and what they mean:
DTC #12: Receiver Memory Bad
DTC #13: Transmitter Not in Range
DTC #14: Non-Valid Transmitter Received
DTC #15: Valid Transmitter Received
DTC #16: Passenger Door Button Depressed
DTC #17: Hatch Button Depressed
95s are NOT OBD2.
On a 94-96 you can check the codes with a paper clip as follows:
You short pin "12" to pin "4" and turn the ignition switch to "On" without starting the engine.
The speedometer will display any codes using the same protocol as the 1990-1993 model but there are some changes in the designation for the modules plus additional modules are added:
Module "1" is still the CCM module.
Module "4" is now called the PCM module (Powertrain Control Module) because automatic transmission computer control was added to Engine Control Module in 1994.
Module 7 (on the 1996 model only) is the RTD module. (This is the Real Time Dampening module which replaced the Selective Ride Control module in 1996).
Module 9 is the ABS/ASR module number from 1994 through 1996.
Finally, Module "A", the DERM (Dynamic Energy Control Module --- (the air bag control module) will be requested to show any codes.
Just like the 1990-1993 display, you read the codes on the speedometer (big) and read the module number on the trip odometer (small).
A series of dashed lines for instance “ - - -“ indicates no more stored codes for that module.
A code showing as “C12” for the CCM module (module #1) means no codes are stored. So C12 is a good thing to see.
Again, you can cause the codes to repeat by turning the ignition off for five seconds and then back on.
Turn the ignition off and remove the short to restore normal operation.
To clear the codes,
1. With ignition "off" ground terminal #12 of the DLC (use bent paper clip to connect pin 4 to pin 12)
2. Turn ignition "on".
3. Press trip/odo button on the DIC until 1.7 appears in the trip
monitor area of the instrument cluster.
4. Press eng/met button on the DIC & hold until "---" appears in the
speedometer area of the cluster, this will clear CCM DTC'S.
To clear PCM/ECM codes do the following:
1. Press the trip reset button on the DIC until the desired system is displayed. In this case it will be 4.0.
2. Press trip/odo button on the DIC until the desired diagnostic mode(4.7) is displayed on the trip monitor area of the cluster.
3. Press & hold the eng/met button on the DIC until "---" is
displayed in the speedometer area of the cluster, this will clear PCM codes.
To clear ABS/ASR codes do the following:
Same as above but you’re looking for “9.7” on the trip odo
And here are the codes
1994-1995: Diagnostic Trouble Codes
DTC #11: Malfunction Indicator Lamp Circuit.
DTC #13: Bank #1 Heated Oxygen Sensor #1 Circuit:
DTC #14: Engine Coolant Temperature Sensor Circuit Voltage Low.
DTC #15: Engine Coolant Temperature Sensor Circuit Voltage High.
DTC #16: Distributor Ignition System Low Pulse.
DTC #18: Injector Circuit.
DTC #21: Throttle Position Sensor Circuit Voltage High.
DTC #22: Throttle Position Sensor Circuit Voltage Low.
DTC #23: Intake Temperature Sensor Circuit Voltage High.
DTC #24: Vehicle Speed Sensor Circuit.
DTC #25: Intake Air Temperature Sensor Circuit Voltage Low.
DTC #26: Evaporative Emission Canister Purge Solenoid Valve Circuit.
DTC #27: EGR Vacuum Control Signal Solenoid Valve Circuit.
DTC #28: Transmission Range Pressure Switch Assembly Fault.
DTC #29: Secondary Air Injection Pump Circuit.
DTC #32: Exhaust Gas Recalculation.
DTC #33: Manifold Absolute Pressure Sensor Circuit High.
DTC #34: Manifold Absolute Pressure Sensor Circuit Low.
DTC #36: Distributor Ignition System High Pulse.
DTC #37: Brake Switch Stuck On.
DTC #38: Brake Switch Stuck Off.
DTC #41: Ignition Control Circuit Open.
DTC #42: Ignition Control Circuit Shorted.
DTC #43: Knock Sensor Circuit.
DTC #44: Bank 1 LF Heated Oxygen Sensor #1 Circuit Lean.
DTC #45: Bank 1 LF Heated Oxygen Sensor #1 Circuit Rich.
DTC #47: Knock Sensor Circuit Or Module Missing.
DTC #48: Mass Air Flow Sensor Circuit.
DTC #50: System Voltage Low.
DTC #51: EPROM Programming Error.
DTC #52: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #53: System Voltage Low.
DTC #55: Fuel Lean Monitor.
DTC #58: Transmission Fluid Temperature Sensor Circuit Low.
DTC #59: Transmission Fluid Temperature Sensor Circuit High.
DTC #62: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #63: Bank 2 RF Heated Oxygen Sensor #1 Circuit Open.
DTC #64: Bank 2 RF Heated Oxygen Sensor #1 Circuit Lean.
DTC #65: Bank 2 RF Heated Oxygen Sensor #1 Circuit Rich.
DTC #66: A/C Refrigerant Pressure Sensor Circuit Open.
DTC #67: A/C Pressure Sensor Circuit Sensor or A/C Clutch.
DTC #68: A/C Relay Circuit.
DTC #69: A /C Clutch Circuit.
DTC #70: A/C Clutch Relay Driver Circuit.
DTC #72: Vehicle Speed Sensor Loss.
DTC #73: Pressure Control Solenoid Circuit Current Error.
DTC #74: Traction Control System Circuit Low.
DTC #75: Transmission System Voltage Low
DTC #77: Primary Cooling Fan Relay Control Circuit.
DTC #78: Secondary Cooling Fan Relay Control Circuit.
DTC #79: Transmission Fluid Overtemp.
DTC #80: Transmission Component Slipping.
DTC #81: Transmission 2-3 Shift Solenoid Circuit.
DTC #82: Transmission 1-2 Shift Solenoid Circuit.
DTC #83: Torque Converter Solenoid Voltage High.
DTC #84: 3-2 Control Solenoid Circuit.(Auto Only).
DTC #84: 2nd And 3rd Gear Blockout Relay Control Circuit.
DTC #85: Transmission TCC Stock On.
DTC #90: Transmission TCC Solenoid Circuit.
DTC #91: One To Four Upshift Lamp(Manual Only).
DTC #97: VSS Output Circuit.
DTC #98: Tachometer Output Signal Voltage Wrong.
To run a diagnostic on the PKE system, connect pins 4 and 8 on the ALDL (see pic below to see pin label order)
And the PKE diagnostic system works as follows:
With pins 4 and 8 connected, the PKE light in the Driver Info Centre will flash the codes.
Here is the list of DTCs and what they mean:
DTC #12: Receiver Memory Bad
DTC #13: Transmitter Not in Range
DTC #14: Non-Valid Transmitter Received
DTC #15: Valid Transmitter Received
DTC #16: Passenger Door Button Depressed
DTC #17: Hatch Button Depressed
95s are NOT OBD2.
#8
Melting Slicks
i understand the procedure but when i went to look for the pins to short i couldnt find them. I remember on my mustang it was underneigh the dash below the steering wheel, very accessable. When i went to look under the corvettes steering wheel it wasnt there. so can anyone point it out for me?
#9
Melting Slicks
i understand the procedure but when i went to look for the pins to short i couldnt find them. I remember on my mustang it was underneigh the dash below the steering wheel, very accessable. When i went to look under the corvettes steering wheel it wasnt there. so can anyone point it out for me?
It may have moved so fish around.
Also check this thread.
http://forums.corvetteforum.com/show...ghlight=obd+II
Last edited by Red Dwarf; 07-29-2008 at 06:19 PM. Reason: spelling
#10
What are 95's then? I have a 95 coupe, and have always had the "SYS", and I've been wanting to track it down and nail it! I think it's to do with my interior lights not turning off ever, so I pulled to fuse for them about a year ago, but its been bugging me.
#11
Drifting
What I said in that thread linked above your post applies to your car. Read your stored CCM error code number, and then google the code number to find out what the it means for your car's CCM. You'll also find any PCM, EBTCM, and DERM codes this way.
#12
Melting Slicks
Do you have an aftermarket radio??????
#13
Yea. I do. It was in there when I got the car. I've been toying about the idea of replacing it, as it is clearly from the mid 90's, and even though I drive the car on a blue moon, I would like to be able to listen to my ipod in there. The speakers are all the stock bose. You think they mis-wired, or hooked something up incorrectly and this is part of my problem? I don't have the 'dimming' lights or anything...
#14
Drifting
#15
I guess Red Dwarf. But whomever wants to chime in
Not to hijink this post, but isn't it possible to have an aftermarket without throwing a code? What's usually causing the code to be thrown?
Not to hijink this post, but isn't it possible to have an aftermarket without throwing a code? What's usually causing the code to be thrown?
#16
Drifting
If the aftermarket radio behaves exactly as the stock radio did, no the car will not think anything is wrong. But if it's kloodged in there without any regard for how the stock setup is supposed to work you'll get codes. In my case, the previous owner got the "finding stations and playing sound" function of it working, and that's all. Therefore the car's circuit that is designed to adjust the dimming on the stock radio lights is now no longer connected to anything, so my CCM doesn't know WTF. The functionality that turns up the radio as speed increases also doesn't work, and so the Vehicle Speed Sensor input circuit is hanging loose and disconnected. These are things that should have been considered had the previous owner actually understood how the radio works.
#17
That makes sense. Funny thing is - my speedo is off and there is a problem with the interior lights. Now I am thinking about it, i wonder if it's related to the piece of crap sony stereo in there. I HIGHLY doubt someone put it in that knew of what they were doing.
I got a code for 'weak battery' but I have put in a new battery a couple months ago after I got that code. These are some pretty sensitive cars!
I got a code for 'weak battery' but I have put in a new battery a couple months ago after I got that code. These are some pretty sensitive cars!