The light comes on when you turn on the cruise function, but will never engage when you press the button. Any ideas?

 

Could be the actuator/servo.

 

check ALL your vacuum lines

 

Hi

Same thing for me on my '95 XJ. Turned out that the rubber bellows on the actuator was torn. I was out of town at the time so I got an inner tube patch kit and patched it. That actually worked for several months but I did replace the actuator. The patch kit can be used maybe for a diagnosis.

Good luck.

bliving7

 

You don't mention having any issues with your ABS, but for what it's worth, if your ABS pump or module isn't working, it can disable the cruise control. It's a bit of a clue when you get an ABS light showing, whereby, if your cruise control is still working, then the warning light is probably just a wheel speed sensor malfunctioning. An easier fix than replacing the pump and/or module.

But I would go with the vacuum actuator or a hose in this instance.