1976 cruise control diag

How do the factory systems work? How do I figure out what is wrong? I can not find wiring diagrams for it or FSM diagnostic procedures or anything in alldata.

It won't even attempt to set, the diaphragm looks new, everything in side the thing looks new, it is getting plenty of vacuum (about 15" @ 55 mph) on one of the wires I get power when I put the switch in the on position, power to another wire when I press the set button and the 3rd gets power when I hit resume, the cable has to be ok because the speedo works and the cable runs through the cruise unit.

Souinds like a bad transducer. The gadget on the fender that everything hooks to.

I am certain that the cruise units from 1970 on up all work the same. There is section in 1970 FSM for diagnosis and service. There is nothing in there about repairing the transducer. Wiring diagram should show the wiring for the brake pedal switch, the turn signal lever with the speed control switch.

One of the easy tests for the transducer, is to turn ign to ON or ACC, then pull the double connector off the transducer . . should here clicking noise if it is ok. No clicking, replace.

Your unit sounds just like the first one I put on my Satellite . . . looked great, etc . . .however, it would not pick up. I did the above test, and replaced the transducer, VOILA, now there is cruise control !! Good Luck . . .

Cheers,

Mark

I could hear clicking when pulling the two wire plug with the ign on.

I just noticed it looks a lot like the one on my 86 5th ave so I am gonna try that one

What vehicle is this on ??? Not that it matters, but the wiring should go like this :

Power from accessory circuit to speed control switch should be the black wire on the speed control switch.

The brake pedal switch is wired between the speed control switch and the transducer (dark blue wire).

On the transducer side of the connector the remaining two wires (black and yellow with tracer) should go to transducer. Connector on speed control side for these two will have white with tracer (matches up to black wire) and yellow (matches up to yellow with tracer).

Sure sounds like it is all wired ok, and that the problem is the transducer. I think mopar made the most robust cruise control unit, and the EASIEST to add to any car !!! Well, certainly any mopar !! And yes, a transducer from the 80's even though it looks bigger, is same unit and wired the same . . . give yours a try.

Good luck

Cheers

Mark

PS - hope to see you at Kalispell show on 14th !!! Look for the purple satellite.

IMPERIAL CLUB

http://moparbvans.proboards.com/thread/1666/factory-cruise-control

After trying 3 units from parts cars I have sitting around I pulled the one from my 5th ave cuz I knew it worked but the bracket is different, well it worked mostly... if you set it at 65 it slowly slows down to 60 and holds it there. Can I adjust one of those screws to get it to hold a little quicker?

There are some adjustment instructions in this link that was provided by IN THE PINK. http://moparbvans.proboards.com/thread/1666/factory-cruise-control