Weird Gauge Problems/Cruise Control

[diezelcrazee]

Ok, this in on my 94 F-350. The cruise control has been intermittent ever since I bought the truck and I have went through the diagnosis thread in the tech articles.

I first noticed several months ago that by pushing various cruise buttons, it would cause my temp and oil pressure gauges to "jump" up 10 - 20 %. When the gauges would do this jump, it would cause my cruise to work.

Lately the cruise has been totally non working, but last night I was driving home and got to fiddling with the cruise buttons again, and noticed it making a huge difference in my oil pressure gauge especially, and some in my temp gauge. The oil pressure gauge would go from 1/2 to max just by hitting the cruise button. Then a really nice thing happened. THE CRUISE took off and started working. This was with the oil pressure gauge doing its thing at max (I don't mean pegged, just all the way over on high).

I am sure this is electrically related. I know that older Ford vehicles had an instrument panel voltage regulator on the back of the dash cluster, does anyone know if they used that in 94?

And does anyone have any other ideas? I love this truck and would really like to get the cruise working correctly.

Thanks

 

[icanfixall]

Sounds to be like you have a ground issue under the dash. Also the back side of the steering wheel has a rotating electrical contact where the cruise control switches make contact when the wheel turns. That too may need some attention. Requires the whel be pulled off. Easy job if you have a wheel puller. If not remove the nut till its on the task couple of threads. Now grab the wheel and rock it from side to side pulling back towards the seat back. When it lets go the nut stops your head from crashing into the rear window if you have a single cab truck. Been there only once and still remember the stars I saw floating around my head. I felt like a cartoon ...

 

[Agnem]

I agree, sounds like a bad ground, or a strange short. The cruise is all tied into the horn circuit.

 

[diezelcrazee]

Sounds to be like you have a ground issue under the dash. Also the back side of the steering wheel has a rotating electrical contact where the cruise control switches make contact when the wheel turns. That too may need some attention. Requires the whel be pulled off. Easy job if you have a wheel puller. If not remove the nut till its on the task couple of threads. Now grab the wheel and rock it from side to side pulling back towards the seat back. When it lets go the nut stops your head from crashing into the rear window if you have a single cab truck. Been there only once and still remember the stars I saw floating around my head. I felt like a cartoon ...

It may be a bad ground, IDK where to start looking for that. I have had the wheel off and checked the contact rings, and felt all that was in order. I have also replaced the cruise buttons as that is what the tests in the tech article pointed to, but that didn't help any.

I agree, sounds like a bad ground, or a strange short. The cruise is all tied into the horn circuit.

The tech article mentions the horn circuit, but the horn blows fine so it seems that relay is working

Thanks to both of you for the replies.