I’m having an issue where my stereo and all my gauges except the tach and speedo will suddenly lose power while driving. This doesn’t happen often and the truck keeps driving normally, and everything will power back on after a few minutes. Anybody have an idea of what may be going on?
LBZ electrical problem
- Thread starter VEfreak
- Start date
I’m guessing it might be a failing relay that all those things have in common. It makes the most sense to me. I’ll try to find the wiring diagrams online, unless anybody already knows a good website to find them and can save me a little time. Any help is appreciated.
Gmupfitter should have what you need.
I don't think there is any relay that powers the cluster. Off the top of my head I believe it comes from batteries, then fuse, then ignition switch to cluster. The radio is directly powered through it's fuse and is turned on via GMLan or canbus or some such signal. The cluster does have two or three power sources though so it is possible you are loosing one of those.
Because you loose radio at the same time I would guess it is a ground that is loose. As I believe they are powered through separate sources
I don't think there is any relay that powers the cluster. Off the top of my head I believe it comes from batteries, then fuse, then ignition switch to cluster. The radio is directly powered through it's fuse and is turned on via GMLan or canbus or some such signal. The cluster does have two or three power sources though so it is possible you are loosing one of those.
Because you loose radio at the same time I would guess it is a ground that is loose. As I believe they are powered through separate sources
Do you still need wiring diagrams? I can find one you need on prodemand and send screen shots or all data DIY allows you to buy for just your specific truck for about $30
Correct. The instrument cluster has 2 power sources:
- Always hot +12v sourced through either the IPC/DIC 10A fuse or the SEO B1 15A fuse with the 8S8 RPO.
- Hot in start or run from the IGN E 10A fuse or the SEO IGN 10A fuse with the 8S8 RPO.
Is the radio aftermarket or stock? Stock radios have 12v sourced through the 15A RADIO fuse and grounded through G203.
The only thing in common that I can think of between the instrument cluster and a factory stock radio would be ground G203 and the serial data bus. Seems unlikely to be an issue with the ground since a ton of stuff grounds at G203.
LBZ_baker, if you could provide some screenshots it would be much appreciated. Unfortunately I haven’t had any time to deal with this issue, being the holidays and all. My wife is already pissed that I have to replace the water pump while we are on our Christmas vacation.
Dndj: It is an aftermarket radio. Once I get some time I’ll pull everything back apart and check ground 203.
Dndj: It is an aftermarket radio. Once I get some time I’ll pull everything back apart and check ground 203.
Ok, if aftermarket it's possible that the radio power was wired into the same +12v circuit as the instrument cluster and this would create another common point of failure between the radio and the cluster. Most pro shops would use an adapter from the factory harness to the aftermarket stereo and thus retain the use of the factory RADIO fuse, but who knows. You would need to take a look and see what was done under the dash for the +12v to the aftermarket radio.
Except for the stereo loosing power, you might try opening the instrument cluster and reflowing the "big" resistors and transformer on the board. If there is a bad solder joint, it could be loosing connection once things either heat up, or get bumped during driving.
Another thing might be the ignition switch starting to go out. I have not been into a newer one, but if there are multiple contractors in it for the various circuits, it could cause intermittent issues in various circuits.
Another thing might be the ignition switch starting to go out. I have not been into a newer one, but if there are multiple contractors in it for the various circuits, it could cause intermittent issues in various circuits.