XK8 Rear parking sensor

[scruggs]

I have seen a few threads on rear parking sensor problems but not for the fault I have on my XK8.

For half the time the rear sensors work fine but for the other half I get a constant tone (as if close to an object) and a flashing 'R' on the auto box selector. This normally occurs after the car has stood all night and less so if the car has been used.

Obviously the flashing 'R' is trying to tell me something, but what?

It is a 2003 XK8 convertible.

Regards

Scruggs

[scruggs]

Ok, i need to find the reverse sensor module. Cannot find it in thr boot. Any other locations.

[jimattfield]

Have you considered low battery, or dew. Some rear park sensors don't like either.

[scruggs]

Thanks, I have tried keeping the sensors clean but that might not solve dampness ingress into the wiring, but I doubt that is the issue.

I will stick the meter on the battery and see what it gives after being parked for a night. It is fairly new though.

[jimattfield]

The sensors are more sensitive to dew/rain/power washers than the wiring although I did cure a beeping error one year by unplugging the connectors at the sensors and using switch cleaner on them. A heavy downpour can still make them play up a bit. Can't say I noticed a flashing 'R' though.

Low volts can also make modules play up, for example if I park up for a couple of days and start on a cold morning I can force a DSC warning message every time but there is nothing wrong with the DSC system at all.

Look for a small rectangular module somewhere in the spare wheel bay marked LJE7352BB.

[TM]

What would be considered to be a low battery?

[scruggs]

Found the module. It is in the fuse box in the boot on a 2003 model 4.2. The flashing R is a red herring. All gearbox symbols flash and the sport mode does not work which appears to be a well known issue on XK's. Apoarently it is caused by a bad electrical contact in a module on the gearbox shifter.