Cruise control blues

[RoyLuke]

So far I have removed and tested the vac pump, R&R the steering wheel switch, panel switch and checked the hoses. Negative function of the cruise control.
Only thing left is the relay. Exactly where is it on the 96 Disco?
If that isn't it, whats left? LOL

Roy

 

[WLDKGDM]

Did you leak test all vacuum hoses on the CC? That is usually the culprit. There is also a T fitting near the brake booster that can crack.

Dan

 

[96discoI]

actually, there are other things it could be. the brain was the culprit for me. what is it doing or not doing? do you hear a click under the dash in the passenger footwell? replace all hoses and tees whether they look bad or not. there is a relay under the dash in the passenger footwell and it is green or yellow. if it clicks when you are above 28 mph, the dash button is activated, and you press the set switch, then the brain is the culprit. if you have no click, it could be both the relay and the brain. good luck and do some more research on discoweb. also, there is a reference on this site about a place in utah that fixes the brains because you cant buy them new anywhere...

 

[d1driver]

Brake switch - on brake pedal
ECU (the brain) - behind glovebox
Vacuum pump - behind drivers headlight
Switch in dash
Switches on steering wheel
Hoses - run from brake switch through firewall to vacuum pump and throttle body

I just got parts from Will Tillery to attempt to fix mine.

 

[RoyLuke]

I have narrowed it down to the brain and/or relay. I tried to listen for the relay "clicking" but it is hard to hear over the road noise. I even turned off the engine but could hear no "clicks"
I can see 5 relays in a tray behind the glove box, 3 yellow, 2 green. How can I tell which is the CC relay?
Roy

 

[evoasis]

Same situation here :/

 

[96discoI]

i cant tell you which is which because over the years they end up getting put back into different holders in the tray. on top of that i have an R380 which changes some things on the relay side. you cannot check the operation of the cruise with the engine off. you have to be going at least 28 mph and have the dash button engaged to get it to engage the pump. under 28 nothing works. turn off the heater, the radio, roll up the windows, and go for a drive over 30mph,press the cc button that looks like a skateboard, and if your steering wheel buttons work right, you will hear a click. then get your ecu rebuilt. if no click,get a new relay. on the r380,it is not the black one. it is either the green or yellow one. i have a bag of extra ones that i use to test with. good luck

 

[d1driver]

I have not heard of a relay for the cruise. The ecu has two little nuts holding it into the slot. A real pain to get out.

 

[cosmic88]

The CC relay is not one of the "green" or "yellow" relays. It is located up under the glove box, and is a tall(er) black relay (four pin). Rmove the fiber board panel which covers the blower motor where the passenger feet are... not the side kick panel under the A pillar.

pics...

The relay

the location next to blower fan motor...

 

[msggunny]

Didnt see it listed, but have you chased the problem via the RAVE's troubleshooting?

It finds the problem faster than trying to figure it out yourself.

 

[ERover82]

What color are the wires to the Hella relay? I've looked there and not been able to find it as I have no Hella relay and the first one there on mine is yellow.

 

[msggunny]

I have narrowed it down to the brain and/or relay. I tried to listen for the relay "clicking" but it is hard to hear over the road noise. I even turned off the engine but could hear no "clicks"
I can see 5 relays in a tray behind the glove box, 3 yellow, 2 green. How can I tell which is the CC relay?
Roy

RAVE troubleshooting procedures will figure this out for you.....