Pcm,tcs,hvac codes
Thread Starter
Racer
Joined: Nov 2008
Posts: 316
Likes: 0
From: Leesburg GA
Pcm,tcs,hvac codes
PCM 0352,0354,0068,0102,0355 TCS1278 HVAC B0361,B0367 What should I check for the PCM codes? Most of those are ignition related. I know the TCS code is traction related but still don't know what to check. The same thing goes for the HVAC codes it says something about the actuator. Any help would be greatly appreciated.
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
http://www.stengel.net/diccodes.htm
The codes are prefaced with "P" or "B" type indicators and followed by "H" or "C" indictors. H or C stands for History or Current. P codes are PCM, B codes are BCM and so on. Reference the above site for the definition of each.
P0352 Ignition Control #2 Circuit
P0354 Ignition Control #4 Circuit
P0102 Mass Air Flow (MAF) Sensor Circuit Low Frequency
P0355 Ignition Control #5 Circuit
C1278 TCS Temporarily Inhibited By PCM
Starting with the ignition codes, it looks like you are having issues with the coil packs but way too many to all be bad packs. I would suggest looking at the ground wire(s) at the rear of the driver's side head and insure that bolt is tight. The MAF is having issues...check it's connector to insure its seated properly and it's connections are clean. What changed from when it was Ok to now? Any work on the engine or other implications that caused all this to show up?
The codes are prefaced with "P" or "B" type indicators and followed by "H" or "C" indictors. H or C stands for History or Current. P codes are PCM, B codes are BCM and so on. Reference the above site for the definition of each.
P0352 Ignition Control #2 Circuit
P0354 Ignition Control #4 Circuit
P0102 Mass Air Flow (MAF) Sensor Circuit Low Frequency
P0355 Ignition Control #5 Circuit
C1278 TCS Temporarily Inhibited By PCM
Starting with the ignition codes, it looks like you are having issues with the coil packs but way too many to all be bad packs. I would suggest looking at the ground wire(s) at the rear of the driver's side head and insure that bolt is tight. The MAF is having issues...check it's connector to insure its seated properly and it's connections are clean. What changed from when it was Ok to now? Any work on the engine or other implications that caused all this to show up?
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
P0352 / P0354 / P0355 are all ignition coil faults---check the coil pigtails
P0102 is a LOW MAF signal below 1300hz---typically thes are just an intermitant code for a brief low signal
I would just clear all these and see if the come back
Same for the HVAC codes
The TCS codes are often related to individual wheel sensors---going over Railroad tracks or driving on a bumpy road can cause a pigtail or sensor to lose connection briefly---I would unplug all the wheel sensor pigtails --clean them with brake-clean--check for broken wires and re-install and clear the codes---
P0102 is a LOW MAF signal below 1300hz---typically thes are just an intermitant code for a brief low signal
I would just clear all these and see if the come back
Same for the HVAC codes
The TCS codes are often related to individual wheel sensors---going over Railroad tracks or driving on a bumpy road can cause a pigtail or sensor to lose connection briefly---I would unplug all the wheel sensor pigtails --clean them with brake-clean--check for broken wires and re-install and clear the codes---
Thread Starter
Racer
Joined: Nov 2008
Posts: 316
Likes: 0
From: Leesburg GA
Codes
Yes, I recently had a 402 stroker engine installed. I also put on new wheels and tires(non-runflats). I guess that is where the service traction is coming in at. So how do I disconnect the sensor that caused this to show up. I'll go out and check the ground wire at the rear of the head and see what happens. Thanks Tblu92 & Dgrant3830.
Thread Starter
Racer
Joined: Nov 2008
Posts: 316
Likes: 0
From: Leesburg GA
I cleared all codes and the only ones that came back were the HVAC and the P0102. The new wheels are not the stock c5 size. I have 285/35/19s out back & 255/40/18s on rear.
Tech Contributor
Joined: Oct 1999
Posts: 41,066
Likes: 9,833
From: Charlotte, NC (formerly Endicott, NY)
The C1278 was showing up because there was a problem with the PCM's ability to perform its part of the traction control function. When the PCM can't control the throttle it sends a message to the EBCM telling the EBCM it can't do its part and that the EBCM should set the TC warning. The EBCM posts this code so you know the problem is totally in the PCM area of responsibility. Don't have to worry about speed sensors, etc. It helps to have codes that point the finger at where to look for a problem.
Bill
Bill
Thread Starter
Racer
Joined: Nov 2008
Posts: 316
Likes: 0
From: Leesburg GA
Pcm
The C1278 was showing up because there was a problem with the PCM's ability to perform its part of the traction control function. When the PCM can't control the throttle it sends a message to the EBCM telling the EBCM it can't do its part and that the EBCM should set the TC warning. The EBCM posts this code so you know the problem is totally in the PCM area of responsibility. Don't have to worry about speed sensors, etc. It helps to have codes that point the finger at where to look for a problem.
Bill
Bill
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Thread Starter
Racer
Joined: Nov 2008
Posts: 316
Likes: 0
From: Leesburg GA
The P0102 is a MAF issue. Service manual suggests examining the MAF itself to insure that there is nothing contaminating the sensing wire or area around it. It also suggests examining the wires going to the MAF for proper routing and any possible damage and the pins inside the connector to the MAF to insure they are not bent/damaged. More extensive testing requires a TECH II or other similar device.
For the HVAC stuff do a search on the codes you have. Lots of reading on what causes the codes and correcting the problems.
Your tire sizes are fine and not an issue.
For the HVAC stuff do a search on the codes you have. Lots of reading on what causes the codes and correcting the problems.
Your tire sizes are fine and not an issue.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
Hi---If you can't trace the TCS or wheel sensor codes by cleaning the pigtails---It may be your tire size selection that is throwing the codes
For your ABS and tract control to work prperly---you front tire heights MUST be close to 1" smaller than the rears--- This is calibrated into the system and i beleive cannot be altered--- IF you have too much more or too much less than a 1" split----frnt/rear-- your tract contrl and ABS may NOT work----the ABS is most important as in a panic stop the ABS will just NOT work---Be careful---Try and experiment and see if the ABS kicks in on a panic stop at say over 50 MPH-- What are the hts of your frnt/rears ????
For your ABS and tract control to work prperly---you front tire heights MUST be close to 1" smaller than the rears--- This is calibrated into the system and i beleive cannot be altered--- IF you have too much more or too much less than a 1" split----frnt/rear-- your tract contrl and ABS may NOT work----the ABS is most important as in a panic stop the ABS will just NOT work---Be careful---Try and experiment and see if the ABS kicks in on a panic stop at say over 50 MPH-- What are the hts of your frnt/rears ????
