Cruise control not working after factory retrofit

[TJRushour]

This is my first Jeep Forum thread and I hope someone can help. I have a 1999 Jeep Wrangler Sport 4.0 with manual transmission. I purchased all OEM Mopar parts for the cruise control. Mopar Servo, Mopar Steering wheel Switches, Mopar Clock Spring with Cruise Control plug, new vacuum lines and luckily I had Cruise Control plug under hood. Checked steering wheel switches and they are for a 1999 Jeep Wrangler and they are working correctly using test meter. Hooked everything up, and I can see the CRUISE "spot" on my light cluster where it should light up, but the blueish cruise light has yet to come on and the Cruise is still not working. Servo does not respond at all. I've researched the internet and found nothing that addresses this situation. I have seen a small white male plug behind the steering column, but do not see where this might plug into anything. Please help anybody. I'm happy to send more pictures, but I have attached one to show the wires in question that are attached to nothing right now.
Thanks,
TJRushour

 

[Chris]

Two things:

1) Is the servo brand new? If not, it might be defective.

2) Are you 110% certain the switches came from a 99? I ask because they changed the switches in 01, and those switches will plug in, but they won’t actually turn the cruise control on. I know this from experience with both the early and late model switches. They look visually identical, but they are in fact different.

 

[TJRushour]

Two things:

1) Is the servo brand new? If not, it might be defective.

2) Are you 110% certain the switches came from a 99? I ask because they changed the switches in 01, and those switches will plug in, but they won’t actually turn the cruise control on. I know this from experience with both the early and late model switches. They look visually identical, but they are in fact different.

Thanks for the reply, Chris!!!
The servo is brand new and a Mopar. I even tried to hook up another old servo I had and it didn’t help either. The steering wheel switches are correct for 1999. I have read many threads on that and see that you MUST have year correct switches and even the numbers on the back of the switches match for my year, from what I’ve read.

 

[whitrzac]

Does the cruise light flash for second when you push the on/off button for the first time when starting the jeep?
If not, the PCM is not getting the cruise on/off button signal.


If it was a dead servo, it would turn on for a few seconds, then off after it errored out. I higher end scan tool that can read model specific codes is immensely helpful for troubleshooting this. It will give you cruise error codes, you can watch what buttons your pressing, why it won't set, etc.

 

[TJRushour]

Chris, could you confirm that the cruise control switches

Does the cruise light flash for second when you push the on/off button for the first time when starting the jeep?
If not, the PCM is not getting the cruise on/off button signal.


If it was a dead servo, it would turn on for a few seconds, then off after it errored out. I higher end scan tool that can read model specific codes is immensely helpful for troubleshooting this. It will give you cruise error codes, you can watch what buttons your pressing, why it won't set, etc.

Chris, after taking the switches back off, I see the attached part numbers. These should be “AD” for a 1999 wrangler TJ, if I’m correct and they are not. Geez!!! The ones I have are for 1998, aren’t they? These are replacements from an eBay seller who sent me the wrong ones the first time. I’m going to get the correct switches and I’ll be back in touch. Dang!! Can’t believe I didn’t double check these!!!

 

[Chris]

Thanks for the reply, Chris!!!
The servo is brand new and a Mopar. I even tried to hook up another old servo I had and it didn’t help either. The steering wheel switches are correct for 1999. I have read many threads on that and see that you MUST have year correct switches and even the numbers on the back of the switches match for my year, from what I’ve read.

Okay then, consider me puzzled as hell!

When I encountered this same issue on mine, it turned out that I had the wrong switches. In your case it just doesn't make any sense. Have you checked the fuse by chance?

 

[TJRushour]

Okay then, consider me puzzled as hell!

When I encountered this same issue on mine, it turned out that I had the wrong switches. In your case it just doesn't make any sense. Have you checked the fuse by chance?

Chris, just for future reference, where is the fuse for the cruise control? I’ve yet to find any information on that online either.

Thanks

Okay then, consider me puzzled as hell!

When I encountered this same issue on mine, it turned out that I had the wrong switches. In your case it just doesn't make any sense. Have you checked the fuse by chance?

Chris, sorry to wear you out, but you are the man to ask. The correct cruise control switches are the “AD” style for 1999 Jeep Wrangler, from what I’ve read. I see several for sale on EBay, but can’t help notice they have “ABS PC” stamped on the back of them. My Jeep did not come with ABS as an added option, so I just want to confirm that doesn’t matter and these AD style switches would work?

 

[Chris]

Chris, just for future reference, where is the fuse for the cruise control? I’ve yet to find any information on that online either.

I'm not 100% sure, but it's either behind the glovebox or under the hood. Both fuse boxes have labels on the underside of the covers, so you should be able to easily see which one is marked for cruise control.

Chris, sorry to wear you out, but you are the man to ask. The correct cruise control switches are the “AD” style for 1999 Jeep Wrangler, from what I’ve read. I see several for sale on EBay, but can’t help notice they have “ABS PC” stamped on the back of them. My Jeep did not come with ABS as an added option, so I just want to confirm that doesn’t matter and these AD style switches would work?

ABS doesn't make a difference with the switches, that has nothing to do with it at all to my knowledge. "ABS PC" is probably just some sort of labeling that actually has nothing to do with ABS brakes.

It's been 6 years or more since I last dealt with the switches, so I can't remember anything about the different part numbers. All I remember for sure was that there were switches for 97-99 models I believe, and then switches for 00-06 models. I remember them having the same connectors, so you'd never know they were different unless you knew the part numbers.

When I lookup that part number you have (56007530AC), it says it's for a 98, which must mean it's for a 97-98 model, so I would have to say you have the right switches. What is the part number for the other one?

 

[TJRushour]

I'm not 100% sure, but it's either behind the glovebox or under the hood. Both fuse boxes have labels on the underside of the covers, so you should be able to easily see which one is marked for cruise control.



ABS doesn't make a difference with the switches, that has nothing to do with it at all to my knowledge. "ABS PC" is probably just some sort of labeling that actually has nothing to do with ABS brakes.

It's been 6 years or more since I last dealt with the switches, so I can't remember anything about the different part numbers. All I remember for sure was that there were switches for 97-99 models I believe, and then switches for 00-06 models. I remember them having the same connectors, so you'd never know they were different unless you knew the part numbers.

When I lookup that part number you have (56007530AC), it says it's for a 98, which must mean it's for a 97-98 model, so I would have to say you have the right switches. What is the part number for the other one?

That’s just it. My Jeep is a 1999, so these won’t work from what I’ve read. The other switch part number is 56007531AC. Shouldn’t mine be “AD”?

 

[Chris]

That’s just it. My Jeep is a 1999, so these won’t work from what I’ve read. The other switch part number is 56007531AC. Shouldn’t mine be “AD”?

I’m not sure what the AD vs AC thing means. I think AD just succeeds AC as the more recent part number.

It sounds like you may indeed have the wrong switches in that case.

 

[Chief Brohician]

TJRushour,

Have you found a solution? I am extremely curious about this topic. I have wanted to put cruise on the ‘98 for sometime now. If you still have the ‘98 parts I could take them off your hands.

Also, most manufacturers install standard wiring harnesses, for different options. Im pretty sure mine has it, but it has been awhile sine I poked around the Jeep. How do I find out if my ‘98 has the harness?

 

[TJRushour]

I’m not sure what the AD vs AC thing means. I think AD just succeeds AC as the more recent part number.

It sounds like you may indeed have the wrong switches in that case.

I’ll let you know. Always something to learn on a Jeep. I’ve got another question for you. I don’t really off-road. Only to a fishing hole from time to time, but want to lift my TJ and put 33’s on her. What’s a good lift for me to get? And what’s a good size and width of wheel that you recommend? I Don’t need a $1,500 Teraflex lift, but this is my daily driver and I’d like a good one that will last.

 

[Chief Brohician]

Chris the admin, put a beginners guide. Under frequently asked questions, there is the beginners guide to lifts. Here is the link to that thread.

https://wranglertjforum.com/threads/a-beginners-guide-to-lifting-your-jeep-wrangler-tj.733/

I’ll let you know. Always something to learn on a Jeep. I’ve got another question for you. I don’t really off-road. Only to a fishing hole from time to time, but want to lift my TJ and put 33’s on her. What’s a good lift for me to get? And what’s a good size and width of wheel that you recommend? I Don’t need a $1,500 Teraflex lift, but this is my daily driver and I’d like a good one that will last.

 

[Chief Brohician]

Where did you get your parts? I would appreciate it if you would list the parts ordered and part numbers. Thanks.

I’ll let you know. Always something to learn on a Jeep. I’ve got another question for you. I don’t really off-road. Only to a fishing hole from time to time, but want to lift my TJ and put 33’s on her. What’s a good lift for me to get? And what’s a good size and width of wheel that you recommend? I Don’t need a $1,500 Teraflex lift, but this is my daily driver and I’d like a good one that will last.

 

[TJRushour]

Where did you get your parts? I would appreciate it if you would list the parts ordered and part numbers. Thanks.

I got them on eBay. Saw many posts stating that’s the best place. For your 1998 just sure the listing is for a 1998 model. You’ll fine them. They are usually between $40 and $75.

 

[Jamison C]

Since I haven’t seen this covered yet, do you have the CC throttle cable?

 

[Chris]

What’s a good lift for me to get? And what’s a good size and width of wheel that you recommend? I Don’t need a $1,500 Teraflex lift, but this is my daily driver and I’d like a good one that will last.

Build your own lift. Ideally you want 4" of lift for 33s, so I'd recommend something like an OME 2.5" suspension lift and a 1.25" body lift. That would literally be perfect and wouldn't break the bank!

 

[TJRushour]

Since I haven’t seen this covered yet, do you have the CC throttle cable?

Jamison, I do have a throttle cable and vacuum hoses and everything is hooked up, but my cruise simply won't light up on the dash when I push the buttons. I've even taken it out and thought maybe the light was burned out, even though my jeep has never had cruise control. To me, the servo simply isn't getting power.

 

[TJRushour]

TJRushour,

Have you found a solution? I am extremely curious about this topic. I have wanted to put cruise on the ‘98 for sometime now. If you still have the ‘98 parts I could take them off your hands.

Also, most manufacturers install standard wiring harnesses, for different options. Im pretty sure mine has it, but it has been awhile sine I poked around the Jeep. How do I find out if my ‘98 has the harness?

Chief, if you google search Jeep TJ Cruise Control harness and you'll find pictures of that harness/plug. If you can't find it, let me know. I'll take a picture of mine, even though mine doesn't seem to be getting power to it.

 

[TJRushour]

I got them on eBay. Saw many posts stating that’s the best place. For your 1998 just sure the listing is for a 1998 model. You’ll fine them. They are usually between $40 and $75.

Build your own lift. Ideally you want 4" of lift for 33s, so I'd recommend something like an OME 2.5" suspension lift and a 1.25" body lift. That would literally be perfect and wouldn't break the bank!

Thanks Chris. Local guy tried to sell me on a Teraflex lift. I know they are very good lifts, but for what I do with my daily driver, I don't want to spend $2,000+ on my TJ's lift. I'll have to buy, new wheels and tires, too. Once that's completed.