Battery not charging, service air bag, service brake system, only 800rpms WOT, engine oil life stays at 5%, fuel filter life no longer shown.

[BraydenVan05LLY]

Hey guys I have a 2005 LLY crew cab short bed 4x4 Duramax. When I bought the truck it was driveable it would just go into limp mode if you got on SOMETIMES, other times ran perfect, it seemed like either a fuel or wiring issue to me.. anyhow I was upset one day and it kicked into limp mode so I decided to go full dumba** and shake the harness. Well ever since the truck starts and idles perfect but you can floorboard it and even on the cts2 it shows 800rpms even at key on engine off. Switching from park to any gear it will try to take off then shut down and max 800rpm at WOT and the oil pressure now does not register and it says batteries not charging plus the other lights in the title but batteries are definitely charging I’ve gone through every harness and ground besides the one directly behind the dash. Has anyone else every experienced this? Also if your keep your foot on the brake and shift to drive it’ll spool up and and bust the tires loose but as soon and they cherp, it shuts back down to 800rpm max. Also if it’s idleing and you give it man’s 2% throttle it will idle like tractor mode anything more and it’ll idle up to 800rpm and if you don’t touch the gas pedal it idles normal. Any ideas? Anyone know where to start next or a solution even?

 

[2004LB7]

LLY's suffer from issues with the injector connectors and harness rub through right at the FICM bracket. Ice pick trick is common for a side of the road fix for the injector connectors. Otherwise replacing the pigtail with a longer one is the more permanent fix. Check the #2 and #7 those are the most common ones to cause issues

The rub through. Make sure you cut the zip tie and inspect the harness where it contacts the bracket.

Also, codes would be nice

 

[BraydenVan05LLY]

LLY's suffer from issues with the injector connectors and harness rub through right at the FICM bracket. Ice pick trick is common for a side of the road fix for the injector connectors. Otherwise replacing the pigtail with a longer one is the more permanent fix. Check the #2 and #7 those are the most common ones to cause issues

The rub through. Make sure you cut the zip tie and inspect the harness where it contacts the bracket.

Also, codes would be nice

I forgot to include in the post that I did the icepick trick then replaced the injector harness on both sides after it seemed to have no effect. Also I inspected the FICM harness and put a piece of hose around it and taped it up as well. I will grab the codes and post them in a few minutes.

 

[BraydenVan05LLY]

LLY's suffer from issues with the injector connectors and harness rub through right at the FICM bracket. Ice pick trick is common for a side of the road fix for the injector connectors. Otherwise replacing the pigtail with a longer one is the more permanent fix. Check the #2 and #7 those are the most common ones to cause issues

The rub through. Make sure you cut the zip tie and inspect the harness where it contacts the bracket.

Also, codes would be nice

I have a video if anyone needs it sent to them to get an idea of what it’s doing, if anyone has come across this issue before and has a solution It’d be greatly appreciated, thank y’all

 

[2004LB7]

Check the wires to the alternator

 

[BraydenVan05LLY]

Check the wires to the alternator

Visually inspecting I don’t see a break in the wires, let me grab my multimeter and see

 

[BraydenVan05LLY]

Found a bare wire on radio harness, looks like someone wrapped the rest of it i electrical tape instead of replacing the wire, found a couple more spots near the plugs to CAN/BUS

 

[TheBac]

Looks like the ground lead out of the radio, but would need pin position to know for sure.

 

[DAVe3283]

That's almost certainly one of the audio ground / drain wires, and I believe that's factory. Older trucks had that wire in a clear plastic sleeve, I'm guessing GM switched to tape to save a few cents.

Sent from my FlashScan V2 using Tapatalk

 

[TheBac]

"drain"wire -- that was what I was thinking, said "ground". Thanks Dave.

 

[BraydenVan05LLY]

I know that’s the ground wire on the radio harness lol, I’m saying also found chaffing at the plugs to the CAN/BUS harness as well

 

[BraydenVan05LLY]

but I figured that could be the cause of a few issues considering you have to remove the radio fuse to program these trucks anyways that for this issues I’m having it might not be all of them but I’m sure it’s playing some part.. right? I’m genuinely asking

 

[1FastBrick]

What Are Some Causes of a P0622 Code?​

There is a range of issues that can contribute to the activation of a P0622 code, but the most common and likely are:

• Faulty, damaged, or malfunctioning generator
• Shorted or open generator harness
• Faulty or damaged connectors in the generator circuit.
• Faulty or damaged wiring in the generator circuit.
• Faulty engine control module (ECM)
• Damage to the alternator rotor

 

[1FastBrick]

P0404 Exhaust Gas Recirculation (EGR) Open Position Performance
P1404 Exhaust Gas Recirculation (EGR) Closed Position Performance

Both of these can cause a drivability issue.

 

[1FastBrick]

DTC U0106 Lost Communication With Glow Plug Control Module (GPCM)

This will not cause a drivability issue.