Cruise Control stops after about 5 minutes

Hello

My 93 RRC LSE 4.2l cruise control works fine for about 5 minutes on the motorway and then cuts out. The light on the dash stays on, but the CC will not switch back on. I give it a couple of days and it works for about 5 minutes again.

I haven't given the system a real good check over yet, but I've checked all the hoses and they all look fine. Anybody any ideas?

Thanks
NKG

I think the cruise control is the same as that fitted on my 91 Vogue SE. Assuming all the vac pipes are O.K. I think you will need to check the spiral cassette. What happens is the ribbon cable breaks causing intermittent contact from the steering wheel switches. It is a bit fiddly and a repair is possible but in reality, it is probably better to get a new spiral cassette - new they are stupidly expensive but search e-bay and specialist breakers and get a second hand one. Assuming you will be removing the steering wheel to get at the spiral cassette - (check rave/workshop manual for procedure)

Check the steering wheel switches themselves, apparently they are known to stick. Carfully prise the switch cover out of the steering wheel and you will find the button underneath - using a multi meter on continuity, push the button and see if it works and check that it breaks contact when you release it.

Assuming you can satisfy yourself that the vac pipes are good, the pump and solonoids are working correctly, the bellows has no holes in it, the spiral cassette is good and the switches are working then I'm afraid you may be in the ring for a new cruise control ECU. I was lucky, I only had to change the spiral cassette and not had a problem since.

The ribbon cable tends to go very close to the multi plug. If this is the case, with care, it can be repaired. Just make sure it's recentralised as per the manual before refitting.

If the CC suddenly stops holding its speed after 5 mins or so its unlikely to be the rotary coupler at fault as it is only used when you press the buttons on the wheel.If thats the case then look at the pump and valve assy - if the vac side gradually loses its suck and the motor does not fire up to replace it there are two possibilities there,plus checking feeds/earths to the cruise ecu.With the wiring digram its easy to check the feeback from the steering wheel switches.A decent multimeter can also be used to monitor the speed input on its Hz scale,from memory it shows around 50hz at 25mph and 100hz at 50 etc.Remember the electronics are getting old now and can slowly fall over,so subbing over a known good ecu is a good idea if all else draws a blank.

Well, with cruise control fault manual in hand I've gone through all the checks and got to the one that says it is the ECU. Searching the web for a replacement it looks like £160 is the average price. I also found the "ECU Repair Centre" in the Netherlands, anyone tried them before?

cheers
NKG

NKG said:

Well, with cruise control fault manual in hand I've gone through all the checks and got to the one that says it is the ECU. Searching the web for a replacement it looks like £160 is the average price. I also found the "ECU Repair Centre" in the Netherlands, anyone tried them before?

cheers
NKG

Click to expand...

Yes,

A good Service and they have know how about the whole system. Repair cost where inclusive shipping costs 100EUR and 1 year warranty!
Regards

Hello

To round off this thread. I sent the ECU to the "ECU Repair Centre" in the Netherlands and for 105EURs I got a recon one back. All works fine.

NKG