As some of you may have read on my post about the progress that was made yesterday, you might recall that I mentioned that the "instrument cluster" for engine temp, oil pressure?, volts, and fuel level aren't working at all. no lights and no movement. My main concern is getting the engine temp gauge functioning and I've read up about the sensor that is located right near the oil cap. Is that most of the battle aside from it properly communicating with the ecu? Any ideas or advice on getting these gauges working would be amazing. Thanks.

 

But the tach and speedometer DO work? if so, it suggests that voltage supply to the cluster is OK.

As for the small gauges you may have a stack-up of faults but corroded contact points on the circuit board on the rear of the cluster are quite common. The fix is fairly easy- remove the cluster and gently clean the contacts--and add a redundant ground wire while your at it. We can give some details on this project if needed.

But you might have other problems as well---such as faulty sending units. You can check by removing the wire at the [oil/water/fuel]sending unit and touching it to ground...with the key 'on'. The gauge needle should rise to the top.




The sending unit for the water temp gauge is on the RH side of the engine near the RH thermostat. Look for the single green wire. (or perhaps green/white? Or some other green/xxx combination? My memory is foggy this morning)




The sensor on the LH side of the engine, aft of the left thermostat, is for the fuel injection system and does indeed talk to the ECU. But it has nothing to do with the temperature gauge on the dash.

Cheers
DD

 

If none of the smaller gauges are working and neither are the lights, it seems quite likely that it is a cluster fault. Were any of them working before?
Greg

 

I posted this: https://www.jaguarforums.com/forum/x...t-work-117268/
Hope it helps you to decide what you'd like to do next.
I am still very proud of how well ALL my gauges work on a 25 year old car. A rock-solid, very good quality instrument cluster after a little investment.