07 6.7 r3500 no crank no start, no comunication with ecm

[raddrake3]

with scanner can communicate,with tpm,pcm ,dash not ecm need help

 

[sag2]

Check for any of the 5v sensor circuits shorted to ground.

 

[IEschrich]

Hi, I may be dealing with a similar problem right now. Has there been any resolution to yours?

I lost the dash, engine, power steering and brakes etc while going 60 towing a trailer. Truck would not start any more. Batteries both at 12.5V and fairly recent. Disconnecting-reconnecting them did not make a difference. Had to be towed to a lonely desert town where truck and trailer remain until this day.. first try was the TIPM since some of the modules did scan, others not (including the PCM). New TIPM did not make a difference. Suspect is now PCM, but I'd like to exhaust all other possibilities first.

 

[sag2]

Hi, I may be dealing with a similar problem right now. Has there been any resolution to yours?

I lost the dash, engine, power steering and brakes etc while going 60 towing a trailer. Truck would not start any more. Batteries both at 12.5V and fairly recent. Disconnecting-reconnecting them did not make a difference. Had to be towed to a lonely desert town where truck and trailer remain until this day.. first try was the TIPM since some of the modules did scan, others not (including the PCM). New TIPM did not make a difference. Suspect is now PCM, but I'd like to exhaust all other possibilities first.

What year truck? Welcome to TDR, you will get answers here.

 

[IEschrich]

2008 6.7l 4x4

 

[sag2]

OK, can the shop communicate with any of the modules on the truck?

 

[IEschrich]

Yes, they were able to talk to the TCM, ECM, and a couple others. Apparently this vehicle runs two CANBUS branches both connected to the TIPM. The branch with the PCM also has some of the modules that were live. Errors stored in those modules were about loss of communication with the PCM. Conclusion was that TIPM malfunction could cause this too, so try this one first. Replacing it did not make a difference though. So the next suspect would be the PCM.

Note I also have a Ravelco theft protection installed on this truck. Having the shop trace those wires to exclude an aged crimp or rodent intervention here.

The only other clue may be that a couple days prior to failure I had the check engine light come on; however it had cleared itself before I could scan the code. The same day the panic horn came on and I had trouble turning it off. This could all be totally unrelated though.

 

[sag2]

OK, your first post says no communication with the ECM, then above you say you can talk to the ECM, TCM and a couple of others. We need to know exactly who is communicating and who isn't. If you can talk to the ECM and the data looks good you should be able to start it.

 

[IEschrich]

Sorry sag2, my first post was mistyped.

On my truck, according to the diagram they showed me at the shop, the PCM is the powertrain control module, the ECM the emissions control module (my assumption). The latter does communicate with the scanner. The PCM does not.

 

[RustyJC]

IIRC (sag2 will correct me if I'm wrong), ECM = engine control module; PCM = powertrain control module.

Rusty

 

[sag2]

I do not think an 08 has both an ECM and a PCM. I believe by that time the trans controller was integrated with the ECM.