Hi all , I have a problem with the instrument cluster on my 1989 4 litre XJ40 , due to a power draw i am using a battery isolator , connecting it back this morning it has done something to my instruments ,has done this before , changed the fuse for cluster before and has fixed the problem . this time no such luck , speedo , tach and all other gauges ( all needles stuck to the right )do not work , and the warning lights , battery , water temp and oil lights are all on . Have have changed all the fuses in both footwells and the ones in the centre console , no difference . The car starts and runs as normal .Has anyone had this problem ? if so how do i fix this ? Are there any relays under the dash that can cause this ? I’m at a loss as what to do . Please help me .

ignition is off .

 

I really dont know, but have you tried turning the isolator back off and then on again?

 

Hi Jerry , Yes have done that , i need to disconnect daily as i'm chasing a battery drain , hense the isolation switch . The car starts and drives as normal but this one time it decided to knock out the important dash gauges as pictured the dials are all to the far right and the speedo and tach don't operate , also the oil light , battery light and the water light remain on after the initial start up lights go out , as i said the car still runs and drives nicely . at a loss.

 

Hi nightstalker,

I assume your car is a 1990 as in your signature and not a 1989 as in the title of your thread, since it has the analog gauges instead of the vacuum fluorescent gauges in the '87-'89 cars.

It does seem logical that a fuse may have blown. I can't recall how many fuses are in the circuits for the instrument cluster, but you can download the wiring schematics for your car at this link:

Jaguar XJ40 Electrical Guide 1990

Another possibility is corrosion on a ground point that is referenced by the cluster, or a loose connector on the back of the cluster.

Cheers,

Don

 

I recently had a dead battery then after it was replaced I had similar problems.
- all gauges stuck on way (mine were opposite to yours... i.e. all to left).
- odometer dead and stuck
Decided to disconnect and reconnect battery and this time I put positive on first....
All fixed!