2015 Tahoe LTZ Gages out and no start

[cgraves817]

Electrical problem that is getting extremely annoying

Occasionally all my gages blank out, like the vehicle is off. Once this happens, it will not start if i turn it off.
Seems to happen during/after wet conditions.
if i disconnect the battery and let it sit, then reconnect battery, i can usually get it to start back up and the gages all work as normal. Until the next rain or snow.

I have replaced the ground harness with AC Delco OEM replacement.
the problem ONLY happens after i drive through heavy rain or snow/slushy covered roads
currently vehicle is with my mechanic but he is scratching his head.
The BCM was replaced last week. Ran fine until it snowed. Problem returned. returned vehicle to mechanic.
all grounds are checked and or replaced. other than the one behind the pillar on left side of dash. Thinking this would not be the problem as it only happens when wet? I would not think moisture would get to that connection.
Thinking about it the other day, i recall occasionally in the past, a problem with the trailer brake system (which i never use)
After a heavy rain or slushy roads, i would sometimes get an alarm about the trailer brake system malfunctioning?
it would not cause the problems i am experiencing with the gages and no-start, but is that maybe a factor with this issue?
A faulty ground within the trailering system?
Any help is appreciated!

 

[Joseph Garcia]

If you had a previous issue with the trailer brake system, try removing the fuse that powers it, and see of your issue goes away. I'm not sure if there any other critical electronics pulling power from the same fuse, though.

You state that you checked all grounds. Did you check the ground on the truck's frame approximately below the driver's foot? This is a major ground, and if it is corroded (and it usually is), you will get all kinds of erratic electrical behaviors. Even if it 'looks' good, take it apart, clean all of the wires and the frame contact, and re-attach, it using dielectric grease.

Other members of this Forum will chime in.

 

[gat0r]

for: trailer brake system

it took me a while to play around w/ it.
battery gauge would dip below 14 & go above 16 , on occasion.

i found it was an issue w/ alternator.
all the electronics are super sensitive & this seems to be the first system that has issue

so i replaced alternator & "trailer brake system" have stopped for now


i am also contemplating the Big 3 (or 4) upgrade
[of note the ground cables have to be run through some sensor (Regulated Voltage Control (RVC) Sensor) & if all neg cables updated largest will be 4 gauge, to be able to fit all inside sensor]




as to your cluster & start issue, i have not seen that, yet

 

[gat0r]

just thought of other users having odd issues.

check your shark antennae
& if you have sunroof check drains.


if there is an issue w/ water getting to your A pillar, check this out:
https://www.tahoeyukonforum.com/threads/where-are-the-ground-points.143921/#post-1814103