C5 losing cruise control

Jelly_Owner · Post by **Jelly_Owner** » 20 Sep 2011, 20:24

Hello,

I have a 2001 2.2HDi C5 auto which has 96k miles on the clock. It's just had a major service with timing belt, 2 new tyres and other stuff done and that all went well. That is until I drove it out of the garage!

One of the things the garage did was to adjust the throttle cable. It now seems to bog down when pulling away from a junction and also as per the subject, the cruise control doesn't always work. If it fails to engage from cold, I stop the car, switch off, count slowly to ten and try again and that usually does it. But it's been known to work and then drop out mid journey. I've noticed it do that as it pulls hard to recover to the previously set speed, such as climbing a hill off a roundabout where the hill is the slip road to a dual carriageway. Once it fails, it won't kick in again until the car is switched off completely and restarted. Not even switching to the accessory position on the ignition switch seems to allow it to work again. It has to be a full switch-off.

I took the car back to the garage, a main dealer, and had them look at it but they said it was working. Well yes, it was, then! But I couldn't persuade them to see how I might get the car to them with it not working because as I turned the thing off, or they did, it would all be ok again.

So is there anything I can look at, or check to see what might be wrong? Or places that I could have the dealer check?

TIA.

wheeler · Post by **wheeler** » 20 Sep 2011, 21:16

Are the brake lights working as they should ? are they staying on intermittantly ?
This would cause both lack of power & the CC not to work.

Jelly_Owner · Post by **Jelly_Owner** » 21 Sep 2011, 09:03

I can only judge of course when I'm not in the car. I watch the brake lights when my wife reverses the car down the drive and they always seem to be working, coming on and going off as expected.

It's not too long since the rear calipers were replaced - the usual Citroen corrosion causing them to twist against the discs. Certainly the brakes work ok.

The car doesn't seem to slow abnormally when I take my foot off the throttle so I don't think the brakes are binding. As for the car bogging down from a start, if I hold the car on the brakes with my left foot and build the revs with my right, it pulls away ok suggesting that it's a control function somewhere that's getting confused.

wheeler · Post by **wheeler** » 21 Sep 2011, 16:50

Sorry when i meant are they staying on i meant the brake lights not the actual brakes.

Jelly_Owner wrote:if I hold the car on the brakes with my left foot and build the revs with my right, it pulls away ok suggesting that it's a control function somewhere that's getting confused.

If you do this it can cause problems as the ECU knows the brakes & accelerator shouldnt be being pressed at the same time & the ECU certainly will be getting confused.

Jelly_Owner · Post by **Jelly_Owner** » 21 Sep 2011, 18:18

> Sorry when i meant are they staying on i meant the brake lights not the actual brakes. (How do I quote your reply as you've done with mine?)

I don't think so but it's not easy to tell

The frequency of the cc not working is decreasing so something in the car is learning and auto adjusting to suit. I just wish I knew what that was. I don't have access to any of the test tools so would be relying on the main dealer. They have been pretty good to me though. Recently when the car decided it had lost a tyre pressure sensor, they fixed that without charging me. They said I was a good customer. Perhaps they'd taken a look at the £1000 bill for the previous service!

Post by **myglaren** » 21 Sep 2011, 21:25

Jelly_Owner wrote: (How do I quote your reply as you've done with mine?)

Click the "Quote" button in the post you wish to quote from.

john alexander · Post by **john alexander** » 25 Sep 2011, 19:29

If you had removed the calipers and swaped sides you would have saved a fortune.