I have recently bought back a previous x type estate I owned about 4 years ago. In the time it has been out of my possession it has mainly been off the road and done less than 1000 miles in those four years. It appeared for sale in my local garage and it was such a good price against my wife's advice I bought it. During this time it has developed a few issues. One isthe cruise control no longer functions. You press the button on the steering wheel and there is nothing no messages on the display or message centre and no cruise control. Not having much knowledge on cruise control I am stumped I check the switchest on both accelerator and brake pedals and they seem ok otherwise I am out of ideas and not able to find any info anywhere else to point me in right direction. Any ideas welcome. Thanks Dave

 

David, the first thing I would be checking is to see if the buttons on the steering wheel are still functioning. If you need steps on how to check those, let me know. The question I have for you is whether you know how to use a multimeter or not. After that, you mention "a few problems". If one of them is dealing with the throttlebody, then yes, the cruise will not work. If you need a set of diagrams for your car, let me know. I just need to know the build month/year of your car since you state it is a 2004 (2 different wiring harnesses for that year car).

 

yes great well I haven't tested the button unsure how o so your help would be greatly appreciated. Not aware of any issues with the throttle body? Buy the garage did mention it had been fitted with new clutch in the last year so not sure if that would affect it?
​​I know no other details of works carried out on vehicle during that time?
it was registered in 2005 not sure the exact year of manufacture but most of the bits seem especially plastic bits are date stamped March 2005 so I am guessing not long after that. Many many thanks Dave

 

David, since your car has a manual tranny, have you checked the clutch switch? That plays into things with your car.

As for build month/year, open up the driver's door and down in the bottom corner (corner of the driver's seat area), you should see a white/silver sticker there. Has things like VIN number, colors of the car, weight ratings, etc. One of them will tell you the build month/year.

 

David, I am taking a stab in the dark since you mention that a lot of the parts are from "2005" that you have an new style car (ie, the upgraded wiring harness). With that being said, I would start with checking fuses F51 and F26 in the passenger compartment fuse boxes. Fuse F51 is good if your 3rd brake light works. Fuse F26 only feeds the cruise cancellation switch. So, if you have a problem, fuse F26 is your most likely situation. If you want to prove that fuse F26 is sending power to the computer, you will need to access the clutch switch (note: there are 2 switches inside the one assembly, so, ensure you get on the correct wire) and then locate the white wire. Using a multimeter set to the 20V DC scale, place the black probe on the body of the car and the red lead on any exposed metal associated with the white wire on the clutch switch assembly. With the car in the RUN position and the clutch not being depressed, you should have 12 VDC on this wire. If not, then you either have a bad clutch switch assembly or a power issue to the clutch switch assembly. To narrow things down, move the red lead over to the red wire with a white stripe. This wire should have 12 VDC on it any time the car is in the RUN position. no power, fuse or associated wiring is bad. 12 VDC, the clutch switch is bad.

Of note, there is a separate switch with a separate power source that goes through the clutch switch assembly for starting the car. This would explain why you can start the car yet not have cruise.

This should hopefully get the cruise back and working.

 

that sound very very promising. It may have to wait till my next day off next week then I will squeeze into the foot well and fuse box and check it out. I will let you know how I get on. Thanks for you extremely valuable knowledge. I will also update the vehicle details. Thanks again Dave

 

 

Toby, this is a short term trial thing, so, please don't keep this in the car long term. What you can do is use a short piece of wire to bypass the switch in question to trick the car into thinking that the switch is good. This will allow you to see if the switch in question is the one that is acting up. LIke I mention, you should only have this installed long enough to do the testing and then remove. i would hate to see you have the cruise over rev the engine because you pulled the clutch switch. There are reasons for the various switch disconnects. But, to do a quick check with this understanding should be just fine.

 

tobyjug: Try adjusting the length of the plunger on the clutch pedal switch, aka clutch cancel switch. It cancels cruise control when the clutch pedal is press.

Remove the switch - careful not to break the plastic tabs that hold it in place - and test continuity with a multimeter. The circuit should be closed when the clutch pedal is not depressed, and open when pedal is pressed. I bet it passes this test. If not, replace it.

Next, adjust the plunger length - give it a good tug with your fingers to fully extend the plunger. Then re-install it and depress the clutch pedal. The plunger will self-adjust to the correct length. Hopefully your cruise control now works.

Your clutch pedal switch has 2 leads, but the electrical connector has 4 wires. This is ok because you have a non-US car. US cars have a clutch pedal switch with 4 leads: 2 to cancel cruise control when the pedal is pressed, and 2 to disable the starter circuit when the clutch pedal is not pressed - a US safety requirement.