On my 1996 VdP XJ6, running like a bird, suddenly the instrument cluster panel is completely dead. I checked and both the 5A and 10A fuses on the rear seat kick panel are ok and the fuse sockets have power. Disconnecting the battery doesn't help, but if I pull and replace the 10A fuse a few of the panel check lights come on temporarily. The directional indicator lights on the panel work normally but nothing else.
Other than the cluster electronics failing, I see no other electronic modules that could cause this. I've tried switching the cluster for two others that I've had on the shelf but neither responds, however it's entirely possible that my spares are bad. My next move is probably to look for a replacement from a working car but before I do that, does anyone know if exchanging an instrument cluster requires any sort of reset to make it work?
I'd greatly appreciate any advice.

 

No reset required. Plug and play ( although your cumulative mileage will be wrong unless you change over the related sub module on the dash)
The fact that you can produce some results from touching the 10a fuse would tend to draw my attention away from the cluster itself…

 

Thanks, that's helpful re the plug and play. I was prepared to live with the wrong cumulative mileage as something unreachable in the instrument cluster programming, but you indicate there's a module containing it? Any detail of that would be helpful.
As far as what the problem is - since the quirk of a reaction to pulling the 10A fuse, I actually had the whole cluster come alive when I started the car and put it in gear, but after turning the key off and trying again it didn't repeat. It suggests there's a single bad connection somewhere that sparked over when I started it. I can't think of a single point failure item outside the cluster that would do that, so am forced by default to assume it's something inside its electronics even though that too seems unlikely.
I have a replacement cluster coming from a running car so fingers crossed. More soon.

 

To continue: as you had suspected it is apparently NOT a fault in the cluster. I have now tried 3 others - one that I bought as good several years ago, one that I picked up along the way, and the latest just bought from a working car. None of them solve the problem.

So what is there outside the cluster that could block everything? There are two separate power feeds, one 5A and one 10A and both have voltage at the fuse and fuses are good so surely one must be getting through. Any ideas very gratefully received.

 

Progress!. If I remove the 10A fuse of the two feeding the instrument cluster (Left rear kickboard fuse F5), turn on the key, and replace the fuse, some of the warning lights come on. But these are the lights such as "door open" that would normally stay on after the initial 5 second scan check of all the lights, and if I start the car, everything on the cluster is working - all the gauges, odometer and trip computer etc. But after I turn the key off, it all goes away and nothing works again when I turn the key back on.
And this is the same for my original cluster and both the spare clusters, they all behave the same way which indicates the problem is not in the cluster. It seems that turning the key on with fuse F5 out allows something to reset to normal.
The one other new thing I notice is that when the cluster is working the SRS Air Bag warning light is on. Maybe there's something in Jaguar's weird security logic that causes the instrument cluster to shut off after a while for an air bag problem.
Anyway the next step is to look at the wiring diagram for something outside the cluster that is affected by F5.

 

And a final update.
If I start the car in the normal way it runs OK but all the gauges and warning lights are dead, the odometer and directional indicator lights work.
If I begin by pulling the left kickboard10A fuse F5, turn the key on but don't start, and replace the fuse, the cluster goes through its normal start cycle with all the warning lights showing for a few seconds. If I then start the car the cluster continues to operate with all gauges working.
So turning the key on with F5 out is allowing something to reset so the cluster can then start normally.

 

Hello,

I have had exactly the same problem with my XJR 6 for a few days.
Have you been able to find a solution to the problem with the instrument cluster in the meantime?

Greetings from Stuttgart

 

On all X300s all 5 fuse boxes the small relay in the corner must close to power fuses 10 , 12 , 14 , and 16

All the rest fuses are hot at all times directly connected to battery cables / bus

To test this relay , have key in run but engine not started , remove relay and it should click in your fingers back to open , swapping option left engine bay fuse box as in this instance only runs the car horns

As you rotate key to start it will purposely drop out a few of these fuse box relays for starter juice priority , may not recommand the fuse box relays as you return key to run

The command from the ignition switch is in the form of a ground path that can be at issue

No new key needed as ignition switch removes ( tricks to accomplish ) from key barrel , same IG switch part # as later V8 X308s

 

Hello, all blue relays switch as soon as they are plugged in when the ignition is on.
Only the relay on the horn does not switch, but the horn works.I also removed and measured the switch on the ignition.Everything is fine here too.Are there any other sources of error I could look for?
Best thanks and many greetings from stuttgart

 

Because a relay does say it is getting the correct command to close but the power contacts inside the relay can be compromised by burnt power contacts

Someone recently stated you can open the relay and clean the power contacts

Reading the switch logic and meter practice was fun to wrap your head around from the wiring guide

 

Final final update: solved with professional help from my Jag Service in Knoxville, who should be worshipped. It turns out there are three (underlined) fuses that affect the instrument panel, you have to read your handbook fuse list very carefully. The third one starts a sequence that gave me the intermittant operation previously reported. Replaced this and all is well. Sorry posted so long after the event but I've moved to NZ.