Truck electrical issues IDEAS WELCOME

obsessed1 · #1 03-09-2018, 03:40 PM

So here's the story. 08 gmc 2500hd 4x4 crew cab long box. Last friday my wife was driving into town and the tranny kicked into limp mode. She pulled over and shut it down, and the truck would not start again. When I got there we noticed the indicator line that tells you what position the gear shifter is in wasn't there. Tried everything I could but could not start the truck. Got it towed to the mechanic. When he looked at it on Monday it still didn't have the indicator line but after turning the key 20 or more times the line appeared and the truck started but the whole left side of the dash board wasn't working properly( needles jumping all over ) then after a few seconds the line disappeared again and kicked the tranny back into limp mode. After a week of tracing possible problems we can't find anything. Now it's been 3 days since we have been able to start it. It won't even start by powering up the starter. The mechanic is stumped I'm stumped. Just looking for possible ideas to try and hoped someone on here had a outside the box idea we could try.

We have replaced the switch on the ignition
Checked all fuse boxes for good connections
Traced all wiring we can find from the steering column
Checked all the grounds

No one has been able to find where that indicator line is powered from yet???

Thanks for any ideas, even simple ones, never know something might just work

Drewski Canuck · #2 03-09-2018, 04:22 PM

Just went through Dodge Diesel Hell with an 03. All it ever was is that flat braid ground strap from the back of the engine to the truck body. Was very white, so it looked normal. But is aluminum corrosion.

Either paint the sucker with CLR, or take it off and soak it in CLR and CLR the places that the bolts go through.

The Tranny is isolated to the engine and relies on the engine ground strap. Engine sits on rubber snubbers so never is grounded to the frame otherwise.

Same thing for the Tranny and its rubber mounts.

Cost you $8 to find out. If it works, I like Kokanee 15 packs. We can get together and cry in our beer about our Trucks.

Drewski

flange · #3 03-09-2018, 05:42 PM

Quote:

Originally Posted by Drewski Canuck

Just went through Dodge Diesel Hell with an 03. All it ever was is that flat braid ground strap from the back of the engine to the truck body. Was very white, so it looked normal. But is aluminum corrosion.

Either paint the sucker with CLR, or take it off and soak it in CLR and CLR the places that the bolts go through.

The Tranny is isolated to the engine and relies on the engine ground strap. Engine sits on rubber snubbers so never is grounded to the frame otherwise.

Same thing for the Tranny and its rubber mounts.

Cost you $8 to find out. If it works, I like Kokanee 15 packs. We can get together and cry in our beer about our Trucks.

Drewski

This is a man who knows. Grounds are really important on modern vehicles.
Buddies 2009 Avalanche similar situation was the grounds. His started by flashing the lights and door locks cycling.

hogie · #4 03-09-2018, 06:14 PM

Scanner won't connect. So that means you can't communicate with any modules?Sounds like a network problem. Should be able to communicate with some of the modules .

Drewski Canuck · #5 03-09-2018, 06:18 PM

If someone had told me to use $8 worth of CLR before spending $1,400 on mechanics, I would have tried the cheap and fast route. But that's just me, in hindsight.

Drewski

overhere · #6 03-09-2018, 06:24 PM

Under the drivers door there is a body mount there should be 2 ground wires there . Clean the contact surface and use a proper bolt and nut to reattach. Get rid of the screw . And at the back in the left rear frame withe all the wires i the loom . There is a resistor for data bus lines. Its used to terminate the bus system. There is a updated plug in cap (old resistor fails and truck no run)

Arty · #7 03-09-2018, 08:16 PM

Saw a youtube vid last week about a phantom electrical problem in an older Benz.

Turns out there was a fuse-box in the edge of the dash right beside the driver's window, which had most of the fuse contacts corroded. (Probably from leaving the window open during a rainstorm overnight.)

The corrosion was bad enough that the can-bus (or whatever it was) although having some electrical connectivity couldn't maintain a proper signal to any processing modules.

I'd check any and all points of potential conductor contact corrosion.

crazy_davey · #8 03-09-2018, 09:09 PM

Quote:

Originally Posted by Drewski Canuck

Just went through Dodge Diesel Hell with an 03. All it ever was is that flat braid ground strap from the back of the engine to the truck body. Was very white, so it looked normal. But is aluminum corrosion.

Either paint the sucker with CLR, or take it off and soak it in CLR and CLR the places that the bolts go through.

The Tranny is isolated to the engine and relies on the engine ground strap. Engine sits on rubber snubbers so never is grounded to the frame otherwise.

Same thing for the Tranny and its rubber mounts.

Cost you $8 to find out. If it works, I like Kokanee 15 packs. We can get together and cry in our beer about our Trucks.

Drewski

Had a look at my 03 and couldn’t see this braided strap, any more details on where it’s located? Passengers or drivers side?

Thanks!

vtecngsr · #9 03-09-2018, 09:36 PM

Quote:

Originally Posted by crazy_davey

Had a look at my 03 and couldn’t see this braided strap, any more details on where it’s located? Passengers or drivers side?

Thanks!

https://m.youtube.com/watch?v=URs_jV75fZg

crazy_davey · #10 03-09-2018, 09:41 PM

Quote:

Originally Posted by vtecngsr

https://m.youtube.com/watch?v=URs_jV75fZg

That doesn’t help my question, hopefully it helps the OP. I was asking Drewski about his 03 Dodge.

Sorry for the hijack.

leeelmer · #11 03-09-2018, 10:00 PM

All gm trucks since 1999 have anti theft
It is a small red light in dash
Cant quite remember if it looks like a lightning bot or something different when you turn your key on

Chuck_Wagon · #12 03-09-2018, 04:22 PM

I’d be suspicious that your instrument cluster itself is at fault.

hogie · #13 03-09-2018, 04:30 PM

Network down? What happens when he checks the network.

obsessed1 · #14 03-09-2018, 04:41 PM

Quote:

Originally Posted by hogie

Network down? What happens when he checks the network.

The scanner won't connect for some reason either so can't even see if it's kicking a code

obsessed1 · #15 03-09-2018, 04:43 PM

Thanks for all the replies. No idea is worth not checking at this point

TylerThomson · #16 03-09-2018, 05:05 PM

Sounds like a ground issue to me. I'd remove and clean all grounds and mounts.

vtecngsr · #17 03-09-2018, 05:13 PM

https://www.autozone.com/repairguide...96b43f81b3c296

JustBen · #18 03-09-2018, 04:32 PM

Had that problem on a 08 gmc work truck. Shifter linkage was worn enough that it wouldn’t always go all the way into gear. Truck started throwing all sorts of fits when you hit a bump or went through mud.

obsessed1 · #19 03-09-2018, 04:40 PM

Quote:

Originally Posted by JustBen

Had that problem on a 08 gmc work truck. Shifter linkage was worn enough that it wouldn’t always go all the way into gear. Truck started throwing all sorts of fits when you hit a bump or went through mud.

Shifter linkage was replaced last winter. Even turning the lever on tranny by hand changes nothing