Odd electrical problems

[Jadalexm]

Hey everyone. New member here and I’ve got an interesting issue. Just bought my 01 Yukon Denali xl and I got it pretty cheap because the previous owner said lightning struck some wires near the truck when it was in Florida and now it’s got a draw on the battery and the gauges go crazy. He said he had the cluster sent out and nothing changed. He installed a lever on the ground of the battery so you can easily disconnect it so it doesn’t drain, and I don’t think that helps much. There’s no way it makes that great of a ground connection. Anyone with experience have an idea on where I can start investigating? I have a huge list of stuff I want to do to this but I have to get this taken care of first so I can at least get it inspected. Haha.

This is a video of the cluster freaking out. Which it does non stop.

https://imgur.com/a/14XGFPH

 

[Tonyv__]

Simple test I learned was to just use a regular 12v bulb and put 2 wire leads on it + and - Make sure the key is out of the ignition and just start pulling fuses 1 by 1 and stick the leads from the bulb in place of the fuse. If the bulb lights up then that circuit could lead you to your parasitic draw.

Obviously a multimeter would work better but last time I had this issue. I didn’t have any tools and a bulb was what I used.

 

[swathdiver]

Hey everyone. New member here and I’ve got an interesting issue. Just bought my 01 Yukon Denali xl and I got it pretty cheap because the previous owner said lightning struck some wires near the truck when it was in Florida and now it’s got a draw on the battery and the gauges go crazy. He said he had the cluster sent out and nothing changed. He installed a lever on the ground of the battery so you can easily disconnect it so it doesn’t drain, and I don’t think that helps much. There’s no way it makes that great of a ground connection. Anyone with experience have an idea on where I can start investigating? I have a huge list of stuff I want to do to this but I have to get this taken care of first so I can at least get it inspected. Haha.

This is a video of the cluster freaking out. Which it does non stop.

https://imgur.com/a/14XGFPH

This guy knows his stuff:

https://www.youtube.com/channel/UCzJWy4r_V89YYt4GBxNaJfQ

 

[rockola1971]

Pull the IC and clean the rear of the circuit board off. I suspect you have silver migration going on there. This will cause the BCM to never goto sleep and IC will go nuts depending on what parts of the circuit are bridged.

 

[Jadalexm]

So I have an update on this issue. Turns out I don’t have a signal at my obd port either. There’s power there, but I can’t connect. I replaced the ecu thinking it was causing that issue and the dash going crazy, but everything’s the same. I’m also trying to fix my air level suspension too cause that won’t turn on. I’m curious if the abs light has to do with that, but again, can’t read codes so I have no idea. Any help is appreciated.

 

[TollKeeper]

Stupid question, have you tried a different OBD reader? A tech2 is going to read your ALC, but any generic one should be able to read the PCM.

 

[Rocket Man]

By ecu do you mean body control module or powertrain control module?

 

[PNWYukon]

Check for rats inside/under the fuse box.

Get a wiring diagram and trace the wires.

If your underbelly is crusty, trace all the grounds and reseat them.

 

[Jadalexm]

By ecu do you mean body control module or powertrain control module?

The pcm. I read somewhere that it could be the bcm causing all the lights on the dash and the low voltage to the obd port.

 

[Jadalexm]

Stupid question, have you tried a different OBD reader? A tech2 is going to read your ALC, but any generic one should be able to read the PCM.

I tried my little matco hand held reader. Then I tried the snap on one from work. The snap on one actually gave me a message that said vehicle voltage to scanner too low.