Engine/Transmission (1994 - 1998) No Cruise control

[ABorchard]

Not often one of these trucks stumps me but this one has.

'95 3500, AT 4wd, with no cruise, all the likely problems have been checked, vacuum, actuator, control and brake switches and three times though the diagnostics in the factory service manual, everything checks out good, still no cruise.



Could it be a bad PCM, wouldn't that throw a code?

Next step will be to trade the PCM from my own truck into it, something I'm a little leery about to see if that could be the problem.

Any other suggestions?

 

[SBozeman]

Did you try spraying the throttle position sensor with electrical contact cleaner. When mine quit working I dowsed it and worked the throttle back and forth and it has worked ever since. That was about 2 years ago.

 

[biggy238]

Check the ground wire and the connection to the frame. Some people have had corrosion problems and mine was completely loose when I bought the truck.

 

[JAmos]

Where is the ground wire located? Just fixed a different wire problem and it didn't have any effect on the cruise. I also checked the easy things(fuses, vacuum lines, electrical connector) with no luck.



Jordan

 

[DJAustin]

I went through the same things on my 95. Ended up being the swithch on the steering wheel. The detent would not hold the switch closed. I have had to replace it twice now.

 

[biggy238]

Mine has a harness that runs down just in front of the inner fender. Mine is shattered so I don't know if you can get to it from under the truck on yours or not.

Mine grounds another electrical connection and my horns about 12-16 inches from the front of the frame. I'll get a picture tomorrow if I can remember.

 

[JAmos]

I went through the same things on my 95. Ended up being the swithch on the steering wheel. The detent would not hold the switch closed. I have had to replace it twice now.

DJ-would the cruise work if you held the on switch down, and is that what you are talking about? I haven't tried that with mine yet.



Jordan

 

[DJAustin]

Yes, I wedged a match book under the rocker and it worked. Eventually the contacts "shifted" out of place, and it would not work this way either. I have replaced this switch assembly twice now. Both times the "on" switch went bad.

It is very easy to remove the switch assembly, and inspect it. Be carefull when you open it up, incase it is OK and you need to put it back.

 

[Andy Redmond]

I too have tested the switchs for continuity and found them "ok," and a new switch solve the problem. So I chaulked it up to an intermittant concern.



I think its like 36 or less from the dealer, not trying to be a parts changer, but we have made our point!

 

[ABorchard]

Parts trading took place before I got a hold of it. So far the vacuum actuator, control and brake switches, have been traded to no avail. Owner was going to trade out the transmission speed sensor today though I don't think that's the problem as the speedo works fine. All the wiring checks out fine also.

I'm still thinking the PCM but ran into something interesting, remanufactured 12 valve PCMs aren't available because there are no cores. Only way to get a reman is to send the old one in for rebuilding. This indicates to me that they don't fail often.

 

[Andy Redmond]

Reman PCM thru Dodge and the aftermarket (standard motor products and others) are available without sending yours in for repair.



A few elec. specialist in my area will rebuild or exchange.

 

[JKouzez]

i am having problems with my cruise also it will hold for a few seconds and then cut out its not the brake sensor because the raod could be totally smooth and it still does it and i even put my foort behind the brake and hold it back with the same result help would be aprreciated because i am not very familiar whith the cruise system

 

[ABorchard]

Any more thoughts?

Have traded almost all the components now including pcm with another truck where the cruise works perfect, still no cruise on this one. All the wires check out, only tests left undone require a DRB scan tool, something most mechanics don't own.

Tearing my hair out on this one.

 

[biggy238]

I didn't see any mention of the TPS being checked. It would have shifting problems if that was bad though, if it were automatic

 

[SBozeman]

I mentioned earlier to try and spray (dowse) the TPS with electrical contact cleaner and work the linkage back and forth. Have you tried that yet?

 

[ABorchard]

I mentioned earlier to try and spray (dowse) the TPS with electrical contact cleaner and work the linkage back and forth. Have you tried that yet?

No, but the transmission is working perfectly.

 

[ABorchard]

I have sprayed the tps but no cigar. I have found a shop with the DRB scanner. So I have to bite the bullet and get it scanned for 55. 00. I have preformed every test that is published in the dodge manuals. My only test that I could not do is the eng speed sensor or crankshaft position sensor. I would think that there would be no tach if this sensor was defective.

 

[SBozeman]

No, but the transmission is working perfectly.

I don't know exactly how the TPS works, but it fixed my cruise control and the transmission was working perfectly at the time. Good luck with the scan. Tracking down this kind of problem can be maddening.

 

[mysteryman]

the solution

The main thing that fails in the first and second gen's is the micro swithches in the steering wheel. I have bought quite a few of the switches from the vendor that made them. I just solder them onto the tiny circuit boards.



The next thing that goes bad in the system is a part called the "clock spring"

It is located directly under the steering wheel. It connects the switches to the main harness. Inside the black can is a spool of ribbon wire. It is the dumbest dam design I have ever seen!!! The way you test it is you take a ohm meter and check continuity of the terminals going in with the terminals going out.

What happens is the ribbon cable breaks inside the spool. Normally it breaks at the ends. I have fixes a few of them but this is not an easy thing to do !!!!!!

I have my doubts that vary many out there will be able to pull it off.

Your local dealer will sell you a new one for about 140. 00 bucks though.



If any one has any further questions contact me with PM

 

[ABorchard]

The mystery is finally solved!!!!!!!!! The problem was #1 the brake lite switch harness

connector. It was shorted out. Replaced. #2 The PCM connector that plugs into the PCM/computer. While checking for the cruise problems I spread the prongs not realizing this was happening. I took the connector apart and fixed the problem. All works well again like nothing happened. THANKS ART