I read through as many threads as I could find, and my problem seems different.

When it didn't engage, I glanced down at the console and the red light was not on, normally it is always on. Tried pushing the switch but no joy.

I am not getting any other warnings e.g. limp mode or anything like that. Only vaguely related occurrences, rear brake lightbulb went out a few weeks back and replaced with one that fit but may not have been same bulb number, but I think cc was still working after that. Also used emergency brake a week ago for probably only the second time in 3 years. It was a short trip back home so cc wasn't used that same day. Quadruple checked that the e brake is off (but maybe a microswitch somewhere is sticking?)

Checked 3 fuses, centre console switch fuse 6, cruise control on/off switch fuse 14 in the drivers side fascia, and fuse 10 Engine control/crusie control vsv under the hood. Tested all with a meter as well and all checked out okay.

Any thoughts?

 

The cruise not working is probably the brake switch mounted down on the pedal area. The switch is 2 switches in one. One for the brake and one to disengage the cruise when you brake.
If the console switch is working correctly the it is the brake switch.
There are numerous threads and tips for changing the switch.

 

If the cc switch does not light up, it is probably the problem. Disconnect the brake switch plug and check for power at the white/blue wire with the switch and ignition on.

 

The problem is usually the brake switch as already mentioned. But when mine did that and also with no errors otherwise and also no red led it turned out to be the ECU. I had replaced the 2 brake/CC switches and it didn't fix it and a couple months later the ECU failed and turned the V8 into a V4. After getting the ECU fixed at ASI the CC was also now functional again.



Dave

 

Thanks all for the input. Looks like I'll be testing for power at the brake switch and then checking the switch itself. Let's hope it's not the ECU, but thanks for the pointer to ASI, as that is at least a reasonably priced alternative should the need arise.

 

I went the simple route, instead of being upside down under the dash. My cruise was fixed by replacing the bad relay under the hood. I forgot which relay it was, but with a little research it should be easy to find. The relay, if it is a simple 4 spade relay, is about $7 at Autozone, and is rated at 40 amps, because it is used for lighting also. If it is a 5 spade relay, most European car dealers sell them, and they are simply called Bosch style relays. Jaguar uses their own type of Bosch relay, and it is brown, but the color doesn't matter. I am older, so climbing under the dash, messing with a two brake switch set up is far down my list......My 2 cents.....Mike

 

Thanks mrplow58, but it turned out to be probable previous error by me.

Using Rev Sams credit card removal system I pulled the shift surround to check the switch (I'm old too so was in no hurry to crawl around the brake switch).

As I lifted it up over the shifter the wire for the cruise fell down. So even though CC has been working for 2 years since I replaced the wood surround, I must not have clicked the wire tightly into place. In my defense the previous owner had buggered the heck out of the switch mounts so I had to do some fancy epoxy work to get them to stay, and I probably was a little gunshy to push too hard back then.

Put the wire back on and light comes on, so I'm guessing I'm all set. Sorry for the unnecessary post, but hopefully others that don't have the limp mode problem will find this thread useful.

mplow58, I think I'll print off your list of vehicles, I have you beat by 2 cars but you have me beat by 5 bikes, I should be able to use your list to convince my wife I'm not crazy.

 

Glad it turned out to be a fairly easy fix. I had that same problem with the top switch. Pressed it one day and it fell inside the console. I used pieces of cardboard wedged around it when I put it back and its stayed put since.

Here is a partial list of some of the cars I've had...


Dave