2014 Silverado electrical nightmare

[carnau]

6 hours ago, Johnbellaville said:

I appreciate your efforts on this it does give me hope I’m going to a shop I was referred to today to see what they say 

Good luck. Keep us informed. If I can help with anything else just quote me in one of these and it will send a notice to my phone. 

[brian2]

On 3/3/2020 at 7:32 PM, Timmer66 said:

My Silverado had a very similar issue. Lots of faults, reduced power and eventual death. And also when the weather was wet/snowy and crappy. Then after sitting would miraculously self fix. Turned out to be a corroded network wire just in front of the rear wheel. When it got wet it grounded the network and nothing could communicate. A bit of solder and some heat shrink solved it. To the credit of the dealership I dealt with, they really worked to dissuade me from replacing the EBCM when I thought it was the issue, saying they had yet to see one fail. So I persevered until I fount the nick in the insulation. 

 

Was this a splice connection or a connector plug?  Was the problem in harness or at plug? Pictures?  Thank you posting your information.

[brian2]

I find this thread interesting.  I had a long list of error code on my 2017 GMC Sierra, which I addressed most with clean the tightening poor frame grounds.  I thought after correcting the ground near the ABS control module, I would have finally cleared the U0121 code.

 

I am down to just three codes U0121, U0140, & B127E.  It looks like I will need to go deeper into the wiring.

 

Where does one get wiring diagrams and connector diagrams from now days?   In the past, I would always invest in shop service manual.  I was shock to see the price for a shop manual given I think I only spent $150 on manual from 1999 GMC Sierra.  It likely make more sense to use online service to manual.  What recommendation at there for shop service manual?  Is ALLDATA my only option?