I have seen a couple fuse panels bad. The fuses check out but something in the board was bad and not putting power out worth a shot if you got one to switch.
Question: lmm wont start after build
- Thread starter 770JOHNNYW
- Start date
I was just gonna suggest that.
Might be ridiculous but are you getting fuel to the cp3? Primed good ? Shot in the dark. Nothing to do with it not spinning over but why it didn't light with the jumper.
yea ive got fuel its not fireing the injectors im pretty sure which like i said i dont even know what codes are in it.
It's gotta be in the connections some where something is crossed mixed not making a good connection if your saying both ECM's act the same. Your going have to double check everything . Good luck
well the som bitch started with the starter button runs perfect but all the gauges don t work nor does the ignition switch...trans takes gear and all that.
There was a fuse ecm1 on the in cab panel that was bad on my lb7 that did this same thing. Probably won't help but I figure you're beating your head against the wall and it's worth a shot
Yea I'm not real sure at this point the damn thing is acting weird like maybe its got a bcm issue or something I may have to haul it to the dealer. It runs great like I said if u jump the starter
So everything works BUT the instrument cluster and ignition switch ,so basically the steering column is dead? Can you communicate with the ECM ?
See if you pulled a connection or pinched something when you pulled the motor? Double check the fuses also don't just look at them test them as they could be blown and you cant tell. Use a continuity tester! If you can't test them then just get fuses and swap them out!
See if you pulled a connection or pinched something when you pulled the motor? Double check the fuses also don't just look at them test them as they could be blown and you cant tell. Use a continuity tester! If you can't test them then just get fuses and swap them out!
still no communication with ecm...thats how i checked the fuses is with a continuity tester. thanks still no luck
Ohm'ed out pin 6 in and 14 data link wires at the obd port. From what I can find in tech link and online you should see 60 ohms at those two pins. I've got 120 says if you see 120 you have a resistor issue. Anybody heard or know anything about this? This thing has to get done.
says if you see 120 you have a resistor issue. Anybody heard or know anything about this? This thing has to get done.
Its a shot in the dark probably but have you've checked all the pins in the ECM plug & bale plugs on the engine to be sure none are pushed in & not making good contact?
There's a break in the serial data loop somewhere. The only person I trust to work on something like this has it at the dealer. Leaning towards gpcm like josh said....not sure wtf could have happened with it but every lmm I work on gives me hell for some reason
I've never had this issue but gonna try to help you out. If your thinking its the GPCM then unplug the connector and find terminal 44 and jumper it to 46. And then jumper 43 to 45. Once you have those two circuits jumpered recheck your high speed circuit at the DLC and see if it dropped to 60ohms. If it did then its the GPCM, if it didn't then your concern is somewhere else.
It does sound like your on the right track though with issues with the data link. What year is the LMM? I believe there is a document out for the early ones stating there are issues with the 120ohm terminating resistor located under the bed.
It does sound like your on the right track though with issues with the data link. What year is the LMM? I believe there is a document out for the early ones stating there are issues with the 120ohm terminating resistor located under the bed.
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Its a 2010 and that's what we're looking at the terminal under the bed hopefully that will point us in the right direction...thanks
Final Resolution?
What was the final resolution?
I have what I believe to be similar symptoms...
Service Traction Control then Service Stabilitrack then Service Trailer Brake System flashes until I push the check mark button to clear all three. Also, when it happens, it completely disables the trailer brake (even while towing my 12,000lbs Airstream at 70+ MPH). It seemed to start out more intermittent but now it's nearly every time I start the truck.
2009 Duramax LMM
Banks Power Pack (BanksIQ 2, Cold Air Intake, Intercooler, DPF back dual exhaust, and EGT sensor installed)
Banks Speed Brake
BDS Lift (7" front & 5" rear)
<90,000 miles
Ranch Hand front and rear replacement, NFab three steps, and bed rail caps all the way around (all powder coated white to match the truck)
What was the final resolution?
I have what I believe to be similar symptoms...
Service Traction Control then Service Stabilitrack then Service Trailer Brake System flashes until I push the check mark button to clear all three. Also, when it happens, it completely disables the trailer brake (even while towing my 12,000lbs Airstream at 70+ MPH). It seemed to start out more intermittent but now it's nearly every time I start the truck.
2009 Duramax LMM
Banks Power Pack (BanksIQ 2, Cold Air Intake, Intercooler, DPF back dual exhaust, and EGT sensor installed)
Banks Speed Brake
BDS Lift (7" front & 5" rear)
<90,000 miles
Ranch Hand front and rear replacement, NFab three steps, and bed rail caps all the way around (all powder coated white to match the truck)