Well, after replacing all of my lines when I first got the truck, trying to fix the cruise, it worked. That was 3 years ago. Lately, it has been falling out at highway speeds, working its way down to not coming on at all. I decided to tear into it yesterday, and this is what I found:

I hooked a test light to each pin on the cruise ECU (little silver box next to the ECU behind the glove box).

Pin 1 - for the vacuum pump, there are 3

Pin 2 - empty

Pin 3 - set button. Under normal operation, this will get positive voltage when the switch is depressed.

Pin 4 - resume button. same as set.

Pin 5 - brake input. This will get positive voltage when the brake pedal is depressed.

Pin 6 - vacuum pump

Pin 7 - vacuum pump

Pin 8 - ground

Pin 9 - lockout. This will get a positive voltage from the ECU if there is a fault, or if the vehicle is not in the drive gear.

Pin 10 - Power from switch

Pin 11 - Speed input. You should see a pulsed positive voltage while driving.

I saw everything just like it should be so I pulled out the ECU. It was a bit of a bugger. Once I had the board out, I saw that pin 11 had only a small amount of solder, and that was cracked. Several others were cracked as well, so I re-soldered the broken terminals, and voila! It works again. Just thought I would put it in writing for people to search that have problems with RAVE.

Hope it helps someone!

 

I have had the same " cut out @ highway speed".....and feel I've covered about everything else, but you have inspired me again !!...I'm going to give this a try..
thanks

 

Thank you for writing and reposting. Do you know if it is normal that if ibturn the car/key off with cc button depressed, I have to press off then on again for cc to work? If shut off with switch off(open) then start car and turn on cc, seems to work again.

Thanks! Tom

 

My old D1 did that. Ended up buying another ecu.

 

NiceTip.. I'll pull mine and take a look. Thanks!
Dave

 

I am about to go down the road of troubleshooting my cruise control, I am having trouble finding a good schematic of the vacuum hose routing, has anyone come across one?

 

I recently had the same problem...the only vacuum hose I was able to find hooked up to the Cruise was the hose from the pump to the actuator (not 100% certain that's the correct term...the cable from the throttle connects to this unit...both the vacuum pump and this unit are located below the coolant reservoir.)

FWIW, I thought there were more vacuum hoses as part of the cruise system, but apparently not...