Efi live question motors lmm 07

[Bdsankey]

I can't disagree the trucks been down for over a year n a half. What happened is I had an injector go out so I figured put witch one first thing it was number 7 witch is front right of motor witch has a 90' so I got the new one also got the pig tail for it said that commonly the plug itself would go bad cause of the turn so y not change. Well the 2 shops I talked to one said the new one didn't need programming so tried it nothing changed in my misfire damn so I ran separate wires from the ecu to the number 7 injector still no change well me not knowing much about diesels got to looking under the dash well for some stupid reason I unplugged my alarm slash remote start unknowingly that's what it was well idk if when I plugged it back inn idk if I mixed wires or anything like that cause stupidly I didn't mark them and every since then it stop cranking by the keys and won't communicate with Amy scanners and we completely removed the alarm wiring from the truck even no luck so again any ideas help thanks in advance

#7 cyl is passenger side rear most. The front driver side is #2.

Passenger Side: 1, 3, 5, 7
Driver Side: 2, 4, 6, 8


If you removed the remote start and now it does nothing it sure sounds like someone damaged wiring and has been unable (or simply hasn't tried) to find the point of the break. Any competent shop should be able to easily handle this job, either they don't want to do it or don't know how.

 

[TheBac]

Broken/cut wiring at ignition switch would be my guess.

 

[Greenmachine07turd]

So they replaced the ECM and BCM and no change? Like Tom said, I would STRONGLY advise that you get the original ECM and BCM back... It sounds more like the canbus is open or shorted somewhere. I'm on the west side of the river and could take a look at the original ECM and BCM on the bench to see if they'll talk if you can get them and want.

Once I get the truck and computers back I may take you up on this cause idk what's going on with it and it's driving me insane

 

[TheBac]

Could be a corroded connection within the canbus wiring. Could simply be an odd ground issue. Could be an overlooked blown fuse/circuit. Could be a broken wire within its sheathing.

 

[NC-smokinlmm]

Or an aftermarket stereo harness.

 

[Cougar281]

Or an aftermarket stereo harness.

Not terribly likely on LBZ/LMM where flashing occurs on the High Speed CAN Bus. Different story with the LB7 and LLY that nearly everything shared the Class2 bus that the ECM was flashed over. That being said, aside from the first few paranoid times I flashed my ECM when my truck was still a LLY, I never pulled fuses and never had issues...

 

[PureHybrid]

Honestly, take it to a dealer if they're willing to work on it. They more or less HAVE to fix it, nowhere else to go from there, infinite source of engineers a tech can get help from

 

[Greenmachine07turd]

Honestly, take it to a dealer if they're willing to work on it. They more or less HAVE to fix it, nowhere else to go from there, infinite source of engineers a tech can get help from

As i agree with you statement and the facts the dealership is the most expensive place and honestly I don't trust them around where I live sadly

 

[Stroked06Goat]

Any update? Sorry to hear about your shit luck. Did they stick you with the new BCM/ECM bill being electronic parts?

If a communication error the ECM frying would be my last check on that new of a truck, its rare as i think someone mentioned. But on the electrical side (and I hate electrical troubleshooting) I've seen where pins of connectors look good but inside they are just backed out enough to not make connection. Or they are corroded just enough to lack connection.
Heck i was just watching Roadkill and they fired an LS motor for the first time in that 67 vette, and one dude spotted the injector wires were in the harness plug backwards and firing the wrong cylinder, so was running on 6. I would have never spotted that!

And x2. GROUNDS, clean them all.