Hi all. Only just joined and thought my story may help someone - as the other posts helped me solve my problem :-)

Bought my 1999 XK8 last week. In immaculate condition despite having done 164,000 miles (though the drivers seat shows a lot of wear)

Anyway, almost immediately after getting the car the 'Low Coolant Warning' started appearing. Checked the coolant level and not a problem. So I just ignored it for a couple of days. Then yesterday all sorts of Electrical Warnings appeared, i.e. Gearbox Fault, Low Water Coolant (still), Low Brake Fluid, and Engine Failsafe Mode - and, of course the car wouldn't start !! After switching on and off about 8 times it then cleared itself (Low Water Coolant warning still on) and I drove to the local pub. Came out and same problem again.

Spent the rest of the evening reading various posts and this is what I did:

(1) Charged the Battery;
(2) Did a 'Hard Reset';

Everything fine for 10 minutes. Then Low Coolant Level Warning came on!!

Re-checked coolant level and everything OK. So (following comments on other posts for which I thank the contributors) I then disconnected the Coolant Level Sensor - and wow - everything went wrong again, i.e. all previous warnings etc.

Then I used a paper-clip to jump the two terminals - and all OK. To make sure I then disconnected the paper-clip and all gone wrong again. So, I'm pretty sure the Temperature Coolant Level Sensor is entirely to blame.

I've now re-inserted the paper clip, taped it up and my next job is to get hold of a new sensor/Coolant box.

In the meantime I've just driven the car about 50 miles. Stopping and switching on and off at various times on the journey and all is as it should be.

Hope this may help someone.

Good luck and safe driving ............... Len

 

Welcome to the forum Len,

That range of faults sounds like a combination of a faulty level sensor and a failing battery. Take care not to ignore the possibility of an overheat situation on the V8 with a genuine low coolant situation whilst you have the sensor bypassed.

When you get a minute, please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some info about yourself and your vehicle for all members to see.

In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

My low coolant level warning comes on if the level drops a couple of millimetres, I have been told that the sensor is far too high up. but never ignore it, it only takes a few seconds to check it. I would concur that it does sound like a faulty battery, when the batteries are on the way out on these cars, all kinds of electrical silliness occurs. I had the same warnings, Restrictive Performance, Gearbox Fault, ABS Fault, and also the windows kept losing their memory and didnt autoshut completely when I opened and shut the doors. I kept charging the battery but same problems, so I bit the bullet and bought a new battery, and have had no faults since.

 

Welcome to the forum jemp, and good information. When you have time please visit thenew member area and introduce yourself:

New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum

 

Classic symptoms of a very "sick" battery. Install a new one, take two aspirins, and call me in the morning.

 

+1 on all the comments.

The Low Coolant message may have an origin different than the others.

There is an exhaustive thread on my Low Coolant message and how I resolved the situation.

In brief, the float inside the expansion tank becomes saturated over time, loses buoyancy and produces false readings. I gave mine
a little "life preserver" to help it float and the problem went away. I still, however, check the coolant level regularly!