I’m trying to figure out why my Cruise control will not work. The green “Cruise” light does not come on when I press the On button. It’s my understanding that the green indicator will activate even when you are not moving (there is a great write up here that explains the theory).

Today I pulled airbag and measured the different cruise switch resistance levels at the clockspring 2-position connector behind the airbag. Oddly the On/Off and Set buttons on the left side had extremely high resistance levels (11k and 17k ohms, respectively). I removed that switch assembly, carefully pulled it apart and used some Deoxit 100 on the contact surfaces. I then had normal readings from that switch; 0.459k and 4.35k ohms. The right switch was also pulled, cleaned and had the same normal readings as it should.

At this point I’m not sure what to do. There IS vacuum at the cruise control servo (I heard a loud hiss when pulling the vacuum line off of it). I did not yet actually get a vacuum reading (minimum 10” of mercury per the FSM). I read on the other forum that the resistance levels change the moment the two-pin plug is connected back together behind the airbag. It would be nice if there was a diagnostic flow chart.

I’m actually considering buying a Micropod II clone from China to get some in-depth data from DRB III emulator.



T20 screwdriver to remove the switch. 8mm bolts hold the airbag on.



Cleaning the right side switch. I heated up the back of the switch assembly first with a heat gun to carefully soften the plastic. Then I used my pocket knife blade to , on the front side of the switch, to pry each of the sides off of the little rocker teeth. I suggest warming the assembly if it is cold outside as cold plastic snaps off and warmer plastic will flex. Note the little silver “ninja stars” over each switch. They will fall out so do this over a table so you don’t lose anything.

 

I've no experience to give you tips but check out page 420 onwards: 8711 XJ 2000 Service (xjjeeps.com)
Also check out page 1051 onwards from the '97 manual: 1997-factory-service-manual.pdf (xjjeeps.com)

 

This is from the '95 manual. The '95 manual IMO is the best for information, although there were major changes '97 onwards:

 

I finally had some time to diagnose the cruise issue today. Yesterday I did replace the brake light switch just as a precautionary measure but no luck. Today I tore the steering wheel cover off to check continuity between the clockspring connector, to the C100 located in the left footwell (has a 10mm bolt that holds it into its socket), and C1 and C3 at the powertrain control module. I do have my own copy of the FSM which greatly assisted.

Verdict: Bad Clockspring

There is good continuity of the Speed Control Switch signal all the way from the C2 clockspring connector to Pin 32 on C3 (Grey PCM). There is no continuity of the “Sensor Ground” at all between the clock spring connectors on either either side of itself.
I’m surprised that RockAuto doesn’t even offer a clockspring with cruise functionality. I suppose I’ll have to get one from Crown.

 

This is odd. A thread in a different forum discusses how part #56009071AE is identical to 56009071. Apparently the “AE” designation was for a TJ yet these guys claim they are identical. Heck, even Dorman makes that part (525-109) and RockAuto has it for $144.79. I think I might give it a try as Dorman has a lifetime warranty versus Crown’s one-year.

edit: seems like this was discussed here before but never actually definitively answered…

 

I can state with confidence that the clockspring Dorman 525-109 works with a 2000 XJ with cruise control. This does not show up as compatible for an XJ though but it works perfectly fine. I will be contacting RockAuto to inform them that it is indeed compatible.
My problem is SOLVED.

Replacing the clockspring was quite easy. Unhook a battery cable and do not start the job for at least ten minutes. 8mm socket for the airbag bolts. 13/16th socket for the steering wheel nut. You'll need a steering wheel puller with 3/8" bolts. While the steering wheel is off it I'd a great time to clean the leather; way less of a mess this way. I used Meguires interior detailer. My leather wheel really needs to be sanded, dyed, and resealed. They sell kits for that. Removing the airbag connector is tedious. In used a fine tipped flat head screw driver to carefully pry it from the side. It pops right off.

 

Hip Hip Hooray!!

 

We LOVE it when people follow up with their solutions! Awesome!

 

I just had to see what the culprit was. I know that people get a little weird about repairing a clock Spring and I do agree it's not an item to screw up due to the airbag launch circuitry there. But as you see, I could have easily fixed this. The culprit was the end of the ribbon that goes to the main big wide connetor. The flat copper conductor had simply unfastened itself. A simple precision solder job would have easily fixed this. Cheaper than the $150ish I spent on the new part. The cable was still lubed with silicone grease and was in excellent condition. I saw a YT video of a guy soldering a break in the middle of the cable - that is insane.