Cruise control not working

[Matthew Bank]

I need some help my cruise control will occasionally turn on and the cruise light pops up but when I go to set it it turns off or if I hit the brake it will still turn off. What could this be

 

[LibertyTC]

Welcome to the forum.
What year is you Jeep?
Once I know, I'll get you the factory service manual. It operates on vacuum & a servo. There are diagnostic procedures in there.

 

[Billwill]

What year/model is your KJ ie. gasser or CRD?

 

[Matthew Bank]

It’s a 2003 liberty sport 3.7 v6

 

[Kevin McKinnon]

It’s a 2003 liberty sport 3.7 v6

Do you have any check engine lights or the ABS light on on your dash? If the ABS light is on it disables the cruise control.

 

[Matthew Bank]

Do you have any check engine lights or the ABS light on on your dash? If the ABS light is on it disables the cruise control.

No

 

[tommudd]

Have you checked the wiring from sensor on the rear diff up to the frame, common area for them to break ( the wiring )
Will cause issues like described at times

 

[Big Al]

? If the ABS light is on it disables the cruise control.

Good to know

 

[Billwill]

I need some help my cruise control will occasionally turn on and the cruise light pops up but when I go to set it it turns off or if I hit the brake it will still turn off. What could this be

Could be a bad Clock-spring randomly turning Cruise Control Off/On.

 

[Matthew Bank]

I have not

Have you checked the wiring from sensor on the rear diff up to the frame, common area for them to break ( the wiring )
Will cause issues like described at times

but where is the harness located?

 

[Billwill]

The harness is from the connector that plugs onto the rear diff speed sensor. The wires...harness...then runs forward towards the engine bay.

You need to physically check that these wires are not rubbing on the cable for the handbrake, the exhaust or anywhere else.