Moved this over here from the "general" forum...

So my XJ during the winter was having the speedo not work until it warmed up occasionally, figured it must be contact issue on the back of the gauge cluster, especially since the battery gauge always shows voltage below 14v despite a new battery...so today I finally took it apart. ALL the contact screws on the back of the cluster were loose, so I removed them, used a wire brush to clean the copper contact points, and screwed everything back in nice and tight. Now, the tach, speedo, and voltage gauge are working great (voltage slightly over 14 like it should be), BUT now the oil pressure and coolant temperature gauge are not working at all, and the fuel gauge is showing past full (despite being currently at half a tank) but also the low fuel light on at the same time? I'd guess a grounding issue, but cleaning the contacts and tightening down the screws should have made that better not non functioning??? Before doing this the fuel, oil pressure, and coolant temp gauges all worked just fine.

Any ideas?

 

On my 94 I had to run a ground wire from one of the GND screws to a grounding point on the body.

 

I ran a wire from the chassis ground to the ground screw for the oil pressure gauge to test, no change.

To reiterate, voltage gauge speedometer gauge and tachometer gauge all work... Temperature gauge and oil pressure gauge show nothing, fuel gauge is pegged to full, and this all happened after I tightened down all screws on the back of the instrument cluster to fix the speedometer.

 

Well when you had it apart, you got somethings working better, but other things, well they stopped working, Suggest you open her up again, and go over all the contacts again, pay close attentions to those things not working, Something got bent, loose, misaligned, or broke when you worked on it. Hopefully it will be evident upon examination.

good luck

PS..
My first car was not equiped with an oil pressure gage, nor temperature gage, in fact it was made with no gas gage. The VW Bug didnt receive a gas gage until 1962, My Bug was older. I eventually added both an oil pressure and oil temperature gage to the Bug, but never bothered with the gas gage. You marked down the odometer miles upon filling up as a gas gage substitute ( they was no trip meter). If the engine started to sputter out of fuel, you kicked over the reserve gas lever with your right foot, a bit above the gas pedal. . That was an exciting procedure at times, say when accelerating to merge onto a busy freeway.
You could also open the trunk, remove the gas filling cap, and peer straight down to the bottom of the tank to get a read on the fuel level.