Thanks to many of you I have tweaked out most of the electrical issues on my XJ6. My next project is repairing the cruise control. It does not work at all. I'm not sure if the problem is electrical, vacuum hose, or an issue with the bellows. Could someone explain to me how this system works and offer troubleshooting advice?

Most appreciated!

 

In most cases resealing the bellows fixes the problem. Remove and clean the round metal end plates and reassemble the bellows using a silicone sealer on the end plates. Make sure to note the orientation of the end plates before taking everything apart.

Easier still is checking the 3 amp fuse and the vacuum supply hose.

Sometimes the release switch on the brake pedal shorts out and fries the transisters in the cruise control "brain".

I might add the the cruise control and trip computer work off of the speedo transducer. Fixing your speedo just might fix the cruise control. Emphasis on "might" :-).

Cheers
DD

 

Here's more detailed info on cruise control problems:

Cruise Control

Cheers
DD