Cruise control intermittent

[skattrd]

Before I start I'll say the car is automatic and I have all ready replaced the brake pedal position sensor, which has made no difference.
When I press the button for cruise the light on the dash shows up, but cruise doesn't engage until I press the "+" button. It then runs in cruise for a few minutes before disengaging, but feels slightly juddery whilst running in cruise.

I think I read somewhere that the cruise control is vacuum operated, so my suspicions would be a vacuum leak somewhere, I may be wrong on this though. If it is vacuum operated where should I start looking for leaks? or I am barking up the wrong tree and should I be looking elsewhere?

The car is a 2000 S80 2.5D SE Auto.

Comments/suggestions appreciated.

[skattrd]

Nearly a hundred views and no comment, so nobody has any ideas?

Can anyone tell me what components there are in the cruise control system? Is it vac operated? if so can anyone tell me where the pump is and I'll just start following/replacing pipework.

Cheers
Chris

[strbryan]

The system is not vac operated and is controlled via the engine ECU.If you have changed the brake switch for a new item which has had no affect the I would be looking towards the steering wheel controls.

[skattrd]

Cheers strbryan - hmmm steering wheel controls, I do not like taking steering wheels with airbags apart. Time to think about how much I want cruise and read up on the whats involved on dismantling the wheel without upsetting anything.

[ShadeTek]

You need to get the codes pulled which will tell you why the cruise was shut-off. Otherwise, it's guess work or replacing parts that aren't n££ded.