Have Jeep Questions? Ask a Jeep Repair Expert for Answers
Hi there. Welcome to our site.
We are technical experts (mostly OEM and ASE Certified Master Technicians) who can tell you how to diagnose and repair your cruise control - the caveat being you supply the parts, tools and basic mechanical skills. At the end, once you're satisfied with our services, you accept our answers and rate the service.
Most of the times, the cause is a failed clock spring in the steering column, behind the steering wheel. When you press the ON switch, you're actually sending a signal to the main computer (PCM) to activate the cruise control (CC); then, as you press SET, the PCM recognizes the vehicle speed at that moment and keeps it constant until the CC is deactivated/turned OFF.
Is the horn working OK? Any Airbag warnings ON? Check Engine Light ON?
OK. Since the cruise control is controlled by the PCM, any failure should have resulted in one or more set data trouble codes (DTC), knowing which can give us a better idea as to where to focus our efforts. If you don't have access to a scan tool, you can drive up to any major auto parts retailer and they'll scan your Jeep's computer for free.
I m not familiar with the tool you mention. Does it plug in to the vehicles's data link connector? Can it read both current and pending codes?
If no codes are present. The next step would be to use an Ohmmeter to check continuity from stop lamp switch to PCM connector C3 terminal 11 (Yellow/Red wire) and then on from PCM connector C3 terminal 32 (Red/Light Green wire) to the CC SET switch in the steering wheel.
Please see attached graphic for PCM connector terminal identification.
No. We're checking for open circuits between the stop lamp switch and the PCM, from the PCM to the CC switch and from the CC switch to the PCM. To do so, I need you to first check continuity on the Yellow/Red wire from the stop lamp switch to the PCM C3 terminal 11; then, check continuity on the Red/Lt Green wire from PCM C3 terminal 32 to the CC switch terminal 1 in the steering wheel. Last, check continuity from the CC switch terminal 2 to PCM connector C1 terminal 4 (Brown/Yellow wire).
To get access to the CC switch, turn ignition switch off. Disconnect negative battery cable. Wait 2 minutes for air bag system to discharge reserve voltage. Remove 2 screws holding air bag assembly to steering column. Separate air bag assembly from steering column and disconnect air bag, horn and speed control switch connectors. Removescrews securing speed control switch to air bag assembly. Separate speed control switch from air bag assembly. To install, reverse removal procedure.
Move the steering wheel from side to side when checking continuity to and from the CC switch to make sure there is good continuity through the clock spring.
Have to log out for a while - dinner time in Richmond, VA. Will be back later tonight to check on your progress.
I see there is no news from your end. I'll be back online tomorrow after 2 PM ET. Hope to hear from you then.
Looking forward to your findings.