Brake Errors During DPF Regen

[SpeedRacer350]

I have a mystery:  I get the ABS and Brake Light error warning lights ONLY DURING REGEN.  The speedo, all gauges and the brakes work fine.  The lights go out after restarting, but will come back if regen is still happening.   I can pull the following codes:

 

• C0055-0f invalid data received from electronic brake control module - signal erratic
• U0100-7f lost communication with engine control module bus - signal erratic

 

I've checked all the chassis grounds, battery grounds (all .3 or .4 ohms) and the condition of both batteries (both 12.7 volts after sitting over a week).  I have replaced the vehicle speed sensor to no avail.  I'd like to think that the EBCM is not bad since it works fine when there's no regen happening.  However, I still need to check the ground to it's connector.  And I am open to replacing it since it's only $130.  So, here are my questions:

 

1. Does anyone know the ground pin(s) of the EBCM connector?
2. If I get the exact EBCM unit, does it have to be reprogrammed for a 100% stock truck? (stock wheels/tires)
3. Does anyone have access to any dealer TSB for this condition or have any other insight?

 

the truck:  2013 GMC 3500 Duramax, dually, crew cab, SLE, 4x4, only 25k miles, clean and pampered

 

thanks in advance!

Edited November 10, 2017 by SpeedRacer350

[newdude]

EBCM has to be programmed. 

 

Ground terminal is the big fat lower left one, in the picture, the closest to the curve of your hand, lower left.  Where that 45'd end is on the connector body. 

 

Quote

 

DTC C0055 0F

This DTC may indicate a intermittent or erratic rear wheel speed signal or mechanical fault, refer to the Diagnostic Fault Information table for possible mechanical faults or conditions. An intermittent connection or wiring concern at the ECM or EBCM, a wheel speed sensor not mounted correctly, a missing tooth or teeth on the wheel speed sensor encoder ring, or electro-magnetic interference (EMI) may set this DTC. Check for DTCs in the ECM or internal fault in the ECM or EBCM.

 

 

Edited November 13, 2017 by newdude

[SpeedRacer350]

Thanks so much for the good info.  I'll check the connector ground this weekend.

On 11/13/2017 at 4:50 AM, newdude said:

EBCM has to be programmed.

Ah, I'm bummed about this.  Does it need programming even if I don't have Stabilitrac?  Will I at least be able to drive it to the dealer after installing?

 

The info about the EMI validates a story I heard from another guy that he got this problem whenever he drove under high power lines.  That would suck.  So, maybe my EBCM is sensitive for some reason, and the EMI or heat from the regen process is causing my issue.

 

 

[newdude]

47 minutes ago, SpeedRacer350 said:

Thanks so much for the good info.  I'll check the connector ground this weekend.

Ah, I'm bummed about this.  Does it need programming even if I don't have Stabilitrac?  Will I at least be able to drive it to the dealer after installing?

 

The info about the EMI validates a story I heard from another guy that he got this problem whenever he drove under high power lines.  That would suck.  So, maybe my EBCM is sensitive for some reason, and the EMI or heat from the regen process is causing my issue.

 

 

 

Yes, Stabilitrak or not unfortunately.  It is a communicating module with other modules in the truck. 

[SpeedRacer350]

UPDATE:  I have checked resistance on all the grounds, checked wiring for chafing, checked wire connectors for bad pins, checked voltage of both batteries, checked the resistance on the CAN bus, replaced the vehicle speed sensor, replaced the CAN bus terminating resistor, and replaced the brake computer... and I'm still having the problem.  

 

The truck runs fine for hundreds of miles, then has this problem immediately as soon as DPF regen starts. Can anyone speculate why/how this could be happening?  What common component between a regen and the brake system could cause this?  

 

Please and thank you.

[Colossus]

heat from the regen causing issues with the wires somewhere?

[SpeedRacer350]

11 hours ago, Colossus said:

heat from the regen causing issues with the wires somewhere?

Possibly, but there's really no way to track that down.  And it seems to kick the error right as soon as the regen actually starts- like after it gets up to a certain temp.  So that makes me think it's an electronic issue.  Plus, GM did a pretty good job routing wires away from the exhaust.  

[Colossus]

Have you tried posting this issue over at www.duramaxforum.com?  More diesel owners over there might have better success getting an answer, sorry bro.  My former truck, a 2012 Duramax had DPF and DEF issues along with early failure of the NoX sensors.  I am not very happy with all the emissions crap on these trucks, it is it the weak link on the Ford, Dodge, and GM trucks.  They all are suffering. 

[SpeedRacer350]

12 hours ago, Colossus said:

Have you tried posting this issue over at www.duramaxforum.com?  More diesel owners over there might have better success getting an answer, sorry bro.  My former truck, a 2012 Duramax had DPF and DEF issues along with early failure of the NoX sensors.  I am not very happy with all the emissions crap on these trucks, it is it the weak link on the Ford, Dodge, and GM trucks.  They all are suffering. 

Yes, I posted on that forum first.  I think those guys are more interested in performance mods and lift kits than CAN bus problems.  So, I came here hoping to find someone that might know how these systems intersect or can at least look up those sub codes in the secret gm tech tables.

 

And I agree with you about these emissions systems.  Even though they are technological marvels, they are super frustrating when they don't work!

[Colossus]

Bummer.  let me ask a few people outside of the forums to see if they have any ideas.  If it were not for the frequency of the emissions systems issues on these newer diesel trucks, I would not mind getting me another one, even though I don't need a diesel for my needs anymore. 

[SpeedRacer350]

Thanks Colossus.  

 

Also, does anyone know the meaning of the diagnostic screens on an Innova scan tool?  It looks to me like it thinks my exhaust temperature is 11,700 degrees!  I had this hooked up while the problem happened, but I couldn't find any useful information in there.

[SpeedRacer350]

UPDATE:  I'm still stumped.  I got an Edge Insight monitor to see if I can see anything interesting on any of the sensors during the problem.  The Insight even has the ability to data log.  However, whenever the truck triggers an error code, the Insight crashes- so it's useless for diagnostics like this. :-/

 

So, my next idea is to get a set of the factory service manuals so I can do a continuity test on the individual wires between the EBCM and wherever else they go.  My assumption is that one of these is energized during regen and it has a short and that's what is causing the problem.  

 

Side note:  this only started happening after an RV dealer put a connector on the end of my 'camper wiring' harness.  Coincidence?

 

Question:  Before I spend $400 on these books, do they show the wire pin locations and routes between the control modules?

 

I have a big big long trip coming up at the end of November and really need to get this fixed.  

 

thanks.  

[Brianibew]

3 hours ago, SpeedRacer350 said:

UPDATE:  I'm still stumped.  I got an Edge Insight monitor to see if I can see anything interesting on any of the sensors during the problem.  The Insight even has the ability to data log.  However, whenever the truck triggers an error code, the Insight crashes- so it's useless for diagnostics like this. :-/

 

So, my next idea is to get a set of the factory service manuals so I can do a continuity test on the individual wires between the EBCM and wherever else they go.  My assumption is that one of these is energized during regen and it has a short and that's what is causing the problem.  

 

Side note:  this only started happening after an RV dealer put a connector on the end of my 'camper wiring' harness.  Coincidence?

 

Question:  Before I spend $400 on these books, do they show the wire pin locations and routes between the control modules?

 

I have a big big long trip coming up at the end of November and really need to get this fixed.  

 

thanks.  

I’m guessing you already did this, but completely REMOVE the “camper wiring” that the RV dealer installed and see if your problem goes away.  If it does, go from there.  My guess is the RV dealer eff’d something up if all that started right after they worked on it.  Make sure you check for wiring they may have accidentally spliced into, then removed when they realized that didn’t work.  Those insulation displacement connectors can wreak havoc on automotive wiring if not installed correctly.

 

Also, if this is a diesel, why did the RV dealer have to screw with anything?  It should have the correct trailer brake/connector already from the factory?

Edited September 25, 2018 by Brianibew

[SpeedRacer350]

40 minutes ago, Brianibew said:

I’m guessing you already did this, but completely REMOVE the “camper wiring” that the RV dealer installed and see if your problem goes away.  If it does, go from there.  My guess is the RV dealer eff’d something up if all that started right after they worked on it.  Make sure you check for wiring they may have accidentally spliced into, then removed when they realized that didn’t work.  Those insulation displacement connectors can wreak havoc on automotive wiring if not installed correctly.

 

Also, if this is a diesel, why did the RV dealer have to screw with anything?  It should have the correct trailer brake/connector already from the factory?

To clarify, I am referring to the factory  'camping wiring' option that is a bundle of wires taped and tucked between the cab and bed.  They just added the correct connector to the end, and I assume that's all that was involved.