I got a 91 xj 4.0 auto, 4x4, tilt wheel

Cruise just stopped working yesterday... I checked fuses, which one is the cruise control on? The cables are connected at the throtle body. Where should I look?

 

still looking for help on this please

 

look by the battery for broken vacuum line i think the cruise is mounted there is you ac vents working correctly they both require vacuum from this line

 

good mornin,

well you have same year as mine, and you have same problem as mine.

OKCJEEp had forwarded me some interesting pdf on this problem...

My cruise control broke a while back, what I had found back then were the actual wires in the steering column which lead up to the turn stalk assembly for the crusie control switch had "broken". I ended up VERY carefully and with much patience re-soldered them to the correct pin connections. (that was couple years ago.)....since then it had worked fine.....fast forward to about a month ago.....drivin from Dallas to El Paso, no cruise control whatsoever.......lovely!

so here is what i have since discovered and further analysis is warranted.........

the cable from the "SPEED CONTROL SERVO" to the throttle body (jeep calls bell-crank, i call accelerator spring) was frayed all to hell, so, i got a new cable , installed it and no joy... am thinking now its the Servo ( i have 265,000 miles on it and its never been replaced.) I am thinking its probably time for a new one as its probably not holding vacuum anymore.

I have fine vacuum pressure right at the Servo so I know there is no problem with the vacuum line.

the only other thing I can do after changing the servo is the engine control module (speed control module, jeep calls it), or the switch on the turnsignal lever itself. so its a work in proccess, any updates I will post here.. If you PM me, I will send what I got as to the JEEP manual description for the cruise control system.

Sooooo,, this week am gonna change out the servo (right next to battery) mounted on the sidewall of the engine compartment. Will see if that does anything!

cpnwrench

 

sorry, I didnt answer your question....

according to the manual, the "STOP/HAZ" fuse and "ACCY" fuse on the main fuse block are associated with the cruise control, (main fuse block being the one inside the jeep drivers side up under the dash. if those are tested good, then the problem is somewhere else.

cpnwrench

 

thanks for the responses, I've had the flu for a few days and will try suggestions tomorrow

 

Update......

an FYI for you in case you have not had the opportunity to look at it.

I found an obscure wiring diagram which indicated that there is a "in-line" fuse for the cruise control electrical circuit.

according to the diagram the 4 amp fuse is taped to near the fuse block assembly in the lower left footwell inside and up under the dash.

Now, I have not looked at it yet as its freezin out there, but.......when sun comes out i am gonna track that sucker down an see if its blown.
i also got a servo unit from a junkyard and see if that fixes my cruise control problem. I have plenty of vacuum right up to and at the servo unit so I am suspecting that. but I will keep ya posted. also I can send you the pdf file i found which shows that fuse...if you want it. let me know

cpnwrench

 

I may have missed it, but when the cruise went out did you notice if the AC or Heater are only blowing through the defrost vents? If so that is typical of a vacuum leak. Check for a rubber vacuum hose hanging from the exhaust manifold. Mine had mysteriously fallen off. Slide it back on if so and you will be good to go. If not, trace it back around checking for leaks.

 

You will notice 4 thin little wires in a black tube at the base of your turn-signal stalk. If you look carefully, you will see one or more are broken. I guarantee it.

You can remove the turn signal stalk by pulling it straight OUT firmly. You will need to replace the 4 wires though.

I used a nice flexable USB computer cable with the ends chopped off. You need to carefully solder the new wires to the broken wires on the stalk and tape or heat-shrink very well. Run the new cable down the inside of the steering column by attaching it to the old broken cruise wires and carefully pulling it down.

Reconnect at the bottom to the old wires again.

Enjoy your working cruise control and curse out GM for using SOLID wires in an area that flexes.


At least GM made it easier to repair on the later systems by adding a plug-in so that you can easily change the busted stalk out.

 

Yep this just happened to me the other day my vacuum hose running next to the passenger fender rite by.the battery was snapped off i plugged it with a screw and whhhabam fixed heat works again and the Cruise

 

Guys!

found the problem in my cruise control situation!!! So I hope that this find will help everyone else out.

Now, I also have a 91 xj 4.0 4x4.. love the jeep! just persnickity problems.

I had written earlier posts about this problem but I am glad I found this thread, as there is some good stuff here from everyone!!!! I really do appreciate it!

It was pretty chilly out today but, I had through insistence from the trouble shooting guide in the shop manual, Especially the part where it says "NO Cruise Engagement" and the first thing they say to check is the vacuum lines for cracks or breaks. So I decided to check the entire vacuum line system all the way from the intake manifold all the way down to the "vacuum reservoir" which is located below and behind the right headlight.

What I found was this; at the opening behind the headlight where the tube feeds down to the vacuum reservoir there is a sharp crease (bodywork opening) as the tube bends downward. Over time this crease has cut into the tube which caused a vacuum leak .....even though I had what appeared to be good vacuum when I checked it at the speed servo. ( I know cause I had the jeep running and pulled the hose off the servo and put my thumb over it and it was pulling air pretty good.)
Needless to say I have removed that hose from the vacuum reservoir and the "t" section near the servo and have used epoxy and duct tape to repair the "crack". I will be installing tomorrow and testing....I do hope that due to this leak over time it has not caused the speed control module to fail. I will send photos of the location and repair once I have tested it out.

DISKMAN,,,,,got a question... you said that you can remove the turn stalk/lever by pulling straight out on it.......I have been trying to find out where how and what technique to use to remove it to test the wiring I repaired some time ago.....according to everything I have read I gotta take the steering wheel off.....but I do remember somewhere reading that the lever CAN be removed without having to take off the steering wheel.....

So you say it can be popped out by pulling "firmly" outward on it?

I don't mean just yanking on it, but pulling straight out ya?
please let me know.....we are talking about the '91 yeah?

This would save me hours of work I don't need to do! appreciate it!

Now, that does not mean that the vacuum canister/reservoir itself may not have cracks or is not structurally intact, but this is a step forward.....

appreciate everyone's input and hope my info helps someone!

 

cruise control update.....

so I fixed the vacuum leak yesterday......


still no joy, no cruise, no workee,

so tomorrow i am going to swap out the servo.

if that does not work, am gonna have to replace the turn signal lever

thats all i can think of left to replace to get this working.

i have already checked out the brake/stop switch and that is ok.

anyone got any ideas?

cpnwrench

 

I hope you get yours going!

I have yet to find my problem...I have sunday as vehicle maintaince day so we shall see

 

more now I think of it.......I am suspecting a connector for the cruise sytem is disconnected...under the dash.

I say this, cause prior to driving to where I am now I had driven from the east coast to dallas and left my jeep at my dads.
I had put in a new headlight switch, cuz the lights started to flicker on and off constantly when i turned them on.
now, in order to replace the headlight switch, i had to take the lower dash panel off. this is what i did in Dallas to install the switch correctly. in doing so I think I disconnected a bunch of connectors for various modules in order to get to the headlight switch, i found the other day i had disconnected my windshield wiper delay module and found this when trying to use the wipers.
gonna check tomorrow to see if something like that is what is the culprit.

as today I found a connector no plugged into anything,,, it is a 7 or 10 pin connector, not sure which. will keep everyone updated....beaverdave if you want wiring diagram an Trouble shooting guide from factory i can send you pdf of the 1990 model.......if will help..

am sure the problem is something simple i have overlooked.

cpnwrench

 

Keeping track of your progress. I have a 2000 cherokee but you have given me many ideas to track down on my own Cruise Control issue. After I get my engine istalled and running this will be one of the things I plan to tackle.