Cruise Control on 2001 Jeep Cherokee

[dinghyboy]

I obtained the servo, clock spring, steering wheel switches and brake light switch from the junk yard off a 1999 (verified VIN 10th digit) jeep cherokee and installed them in my 2001 Jeep cherokee. The installation went easily but the cruise control is not working. The on/off button turns on the cruise light on the dash, but I can not set the cruise control by the set button. The resume/accel button does not increase speed.

 

I have made sure the brake lights are operating properly and are not on.

 

I don't think it is a clock spring issue since the horn works and the airbag light goes off.

 

I visually inspected the vacuum lines and they look okay. I put a vacuum pump on the line at the manifold connection. I pumped it up to 20 (inches?) and it bled down to 10 and then held at that point.

 

What do I do next?

 

Does it need to hold more vacuum than that?

 

How do I test the electronics or the servo to see if they are okay. If anyone has instructions or access to a manual for diagnosing the cruise control it would be much appreciated.

 

Thanks,

 

Gavin

[MeanLemons]

They had different switches on the steering wheel for certain years in the 97-01 range.  You may had gotten wrong ones. 

 

 

[Sir Sam]

3 hours ago, MeanLemons said:

They had different switches on the steering wheel for certain years in the 97-01 range.  You may had gotten wrong ones. 

 

 

 

99 should be the correct year cutoff, also if you get the wrong ones the cruise light won’t turn on. 

 

It’s possible the left switch is good but the right switch is bad, check that you can measure resistance through the right switch and that the resistance changes when you press the buttons. Verify that you can read resistance through the plug to the left switch and that resistance changes when you press on off. 

 

I don't have the resistance values offhand but you can see the resistor color codes on the back of the switch as well. 

 

You might have somehow gotten a 98 right switch, not likely but possible. 

[Dzimm]

My accel/resume button on my 97+ truck is extremely touchy.  I have to hit it in just the right spot or it won't work.  I'm guessing you just have a bad switch much like mine. 

[Eagle]

But he can't engage cruise, and the SET button is on the left.

 

Is it possible that the brake switch isn't adjusted correctly, and you can't engage cruise because the "brain" thinks the brakes are on?