I love this 2003 XJR V8 Supercharged but, it drives me nuts sometimes. Here recently my ABS amber light comes on putting the car in restricted performance. I know its possible a sensor may be going bad. No rust from winter driving, just rolled on 69,000 miles. very clean and well maintained. I have noticed when backing up the rear breaks will squeal and I intend to get new breaks soon. Is it possible the breaks needing replaced will cause this light to come on? I have not hooked up an OBD.
btw, When I shut the car off the light goes away and all is good. It appears to come on in very slow driving conditions, Never noticed it when hwy driving.

 

Dont think a brake problem would put the car into RP mode unless its ABS related in which case you would get other warning messages.
Invest in a cheap scanner and read the stored codes - this will at least give you a starting point in tracking down the problem. Does the car run ok in RP mode regarding engine performance and gearbox shifting ?

AndyP

 

A cheap scanner won't pull c codes (drivetrain) only Jaguar IDS/WDS. But saying that a cheap OBD reader is a must for engine codes and XJ owners, it generally pays for itself first time it's plugged in.

I've got to ask, how old is the battery?

Brakes squeak in reverse? sounds like a pad edge catching, how many miles on the pads/shoes? Hand brake adjustment is easy I adjust by hand and feel to set it up. A lift helps or you develop good abs

Sensors/rings are an easy item to check along with their link leads.

An ABS fault doesn't usually put the car in restricted mode. Is there an engine light on also?

 

Off the wall, but I had this the other day after my car sat on a steep driveway with parking break on for about 10 days. Had to fiddle with the p break a bit and restart the car for it to go away.

 

I'm not sure how old the breaks are but the pads look "okay". I have an inexpsive obd I'm goin to have a few min soon and I'll post codes. In RP mode it shuts down to a crawl, a restart clears and it runs fine. The battery is a concern, I am hearing many issues concerning a dyeing battery. I'm not sure about how to hand set the tension, I can speak to my mechanic on this. I appreciate all the post, you guys are the best.

 

You're doing this on purpose, right?

If it breaks, it is broken. If you want it to stop, you hit the brakes.