Gauge Cluster Issues

[Woodshumvee]

With the humvee running i am able to get the back lighting to work but no actual function from the gauges. Oil pressure needle jumps to 0 then stops. Nothing from volts or fuel. Tanks full and bats are new. I tried a new oil gauge just to see and it does the same thing. Thought it was weird that all the gauges don't work. pulled the face panel and all the connections are good. What do you think it could be? Thanks

 

[NDT]

The gauge panel needs to be well grounded. There is a supplemental grounding harness available that helps with these issues.

 

[Woodshumvee]

Thanks NDT. Found a good write up on supplemental grounds. Going to give it a try tomorrow

 

[m38inmaine]

I had one doing the same thing and it was the ground.

 

[Retiredwarhorses]

There is a ground not only on the panal, but a ground that passes from the engine side to compartment side for instrument grounding...this must be clean.it can only be accessed by removing the inst cluster, it's behind the vent cables' upper right corner....I personally replace the ground stud with new 1/4-20 threaded Rod...

 

[Woodshumvee]

Thanks guys. I ended up finding a ground plug disconnected right over the trans in the ground cable cluster and it looked like someone had cut another ground wire at the plug. I had to cut the wire cover back to get the end and solder a new connection. Once I pluged them both in all my gauges worked.