My next project is to resolve my non-functioning cruise control. Just thought I'd ask if there are any obvious fixes (like remembering to set the park brake to retract/extend the top) before i start veering of into wiring and pneumatic diagrams. Any input appreciated!

 

Not sure there's anything that simple, but it's very common for the bellows to just stop sealing after 30 years of heat. Pretty easy to test it & whether any solenoids are stuck open (squeeze it together, do you hear any hissing?) & not difficult to just reseal with silicone

 

I’ll check it! Thanks.

 

When I squeeze the bellows, I hear air hissing...but somewhere else, not at the bellows. Should the bellows maintain pressure when i squeeze it? It does not.

 

The V12 bellows is the ones that are troublsome, the later 4.0 ones generally are not. Typically, the Hella system in the XJS is very durable.

If I had to guess however, I would start at the microswitch that is at the shifter. If it isn't sensing that the lever is in D, it won't allow the cruise to work.

 

I will definitely check that. Thanks.