Hi,

I just purchased a 2001 cherokee Xj sport (police package).

The cruise control light comes on, but when I hit “set” it doesn’t do anything.

I did a little research, and replaced the vacuum hose (it had snapped in half) and now it blows air out of the correct vents (not just the defrost) and also tested the vacuum line and it has suction. But the cruise control still does not work. Also, the rear brake lights work, and the horn works as well. Any suggestions as to where to look next?

I know very little about cars, so any help would be greatly appreciated!

 

If you have access to a salvage yard, go find the cruise control unit itself. There's really nothing else to go wrong with 'em, other than what you already said about the vacuum line. As you noticed your vents began to act right too.. they run off vacuum. Salvage price for cruise control on my '93 GC was only about $28. Good luck!

 

I had same issue with my 2001. Finally discovered that the brake mechanical switch, which is directly under the dash in line with the steering wheel, and very hard to see, was faulty. Replaced and now works. The issue was the switch was sending "braking" to the ECM, which then would not engage the CC.

 

Same here, my 2001's brake switch had a bad set of contacts.
The 2001 brake switch has three sets of contacts, two are used for the cruise control. Failure of one of the contacts is common and prevents the CC from setting. The switch can easily be removed and tested with a multimeter. Other common problems are a corroded plug on the servo, a cracked clock spring and one or more defective switches on the steering wheel.
All can be tested.

A FSM is a handy device for troubleshooting this and other electrical issues, save your money and buy one.

 

Ok, I ordered one, it should be here in a week.

 

Ok, Is there anyway you can send me a picture of where the brake switch is or what it looks like? I tried googling it, but I’m getting a lot of different result.

 

Ok, never mind. I found the brake switch and replaced it and it works now! Yeeeeeeeeeeeeeeeeees!!! Thanks for the help!

 

Pictures as requested!

 

NIce !! Looks to be in great shape...