Hello all,

As the title states, my 97 XK8's a/c compressor clicks on & off (hyper-actively at that, sounds like Morse code). The climate control is completely OFF.

Has anyone else experienced such an issue? I tried searching older posts, but found nothing related to cycling when climate control is off. Perhaps some hints as to where to begin? Any help is greatly appreciated.

 

Compressors will run anytime the system is on any kind of defrost setting, but still, with it turned off, I think it shouldn't happen.
Maybe try having the air directed at the footwell only. Then turn off the system and see what happens.

 

For now, I have removed the A/C compressor relay.

For anyone else coming across this post in the future, it is the brown relay in the compartment which also holds the brake fluid reservoir. Took me a while to figure out...

 

Did you try swapping the relay with another one?

 

Thanks! Not sure why I didn't think of that one.

Sadly, I got the same result. At least I now know the relay is good...

 

I know the wiring diagrams for the XJ8 are available on this site, have you tried searching for the XK8 ones?

 

The relay is controlled by the ECU and may older ECUs develop faults due to leaking capacitors. Time to peak inside the ECU and look for physcal evidence of (dark brown stains around a capacitor can). Disconnect the battery first.