Mud-club

Vehicle & Technical => Range Rover => Topic started by: Tel on August 12, 2009, 16:19:15

Title: P38 dse cruise control problem
Post by: Tel on August 12, 2009, 16:19:15

Got an annoying problem my cruise control only works when it wants too is there any common problems I can check
I take it this systems not vacum opperated like the v8s?

Any help much appriciated

Title: Re: P38 dse cruise control problem
Post by: Rossko on August 17, 2009, 09:41:14

If it is like the V8s, it is vacuum operated, so check the pipes and actuator bladder.   It has a private electric vacuum pump which can seize up.

Title: Re: P38 dse cruise control problem
Post by: Range Rover Blues on August 18, 2009, 20:42:17

My LSE plays up because of the gear slector switch, it only works intermittantly.

Title: Re: P38 dse cruise control problem
Post by: Tel on August 19, 2009, 08:58:58

Right I'm really stuck on this now as I was using it lastnight and it would work for about 10 seconds then turn off it's defently not the brake switch causing it either any ideas?

Title: Re: P38 dse cruise control problem
Post by: Range Rover Blues on August 24, 2009, 00:09:59

I got pee'd off with mine so I built a "tell-tale", a strip of veroboard with one LED for each input or output so I can watch what's happening, I wired it into a spare  cruise ECU because I has already swapped the ECU to no avail.

Title: Re: P38 dse cruise control problem
Post by: waveydavey on September 16, 2009, 07:26:53

On the diesel the cruise control is incorporated to the DDE so if you have no other engine problems it must be a switch input.
Brake
Clutch
handbrake
steering wheel controls
dash switch

If its a manual I would have a look at the clutch switch

Title: Re: P38 dse cruise control problem
Post by: Tel on September 16, 2009, 13:39:25

its an auto

no other egine problems no i think it might be the steering wheel switch ill be looking into that

thanks mate

Title: Re: P38 dse cruise control problem
Post by: Rossko on September 16, 2009, 18:25:03

Do you have this gubbins?
http://www.rangerovers.net/repairdetails/cruisecontrol.html
What's completely missed out of the description there is the little electric vac pump, where the bottom tube goes.

Title: Re: P38 dse cruise control problem
Post by: waveydavey on September 17, 2009, 06:46:25

He won't have; as I said on the Diesel it's part of the DDE; as in it is 100% electronic, no actuators or anything anywhere in the system, it just tells the engine computer how fast to run the engine.
It is a damn good system; essentially nothing to go wrong bar the switches.

Title: Re: P38 dse cruise control problem
Post by: Tel on September 17, 2009, 12:40:06

this is making me think as i have just had the becm replaced under the seat ans it used to work ok beforehand and now it only works when i wants too would this be connected or is it on a differant control unit?

Title: Re: P38 dse cruise control problem
Post by: waveydavey on September 18, 2009, 07:47:47

It could be connected; the Cruise control is actually a part of the DDE which is the computer in the plastic box just behind the battery BUT that is told what to do by the BeCM and the BeCM is what receives the inputs from the controls.

It could be just the plug on the BeCM that has the wire from the controls?

Title: Re: P38 dse cruise control problem
Post by: Tel on September 18, 2009, 11:37:19

I think what I will do In that case is get a contact cleaner and clean up all the plugs on the bcm