I have a 93 2wd. the cruise and overdrive quit working at the same time,but while still rolling at speed I can place trans in nuetral, turn off the ignition, restart the truck and both the cruise and od will work again.I've only had this truck about 6 months.The only thing Ive replaced is the ignition switch,which a friend of mine gave me used.any help will be greatly appreciated,

 

I believe that's a sign of an ailing PCM, but I'm no expert.

 

Check to see if the electrical system is charging that is another sign of a pcm problem

 

these tucks have clock springs this will affect the cruise this carried over to my 2001 just a bit of FYI

 

Thanks for the info.I did fail to mention that I noticed that while driving at night the lights dim and the amp gauge flucuates (you know what I mean)at the same time.What is a clock spring?

 

sounds like the PCM.

The clock spring is behind the horn (on the steering wheel) it enables to wires to go though the steering column without binding up. the horn and cruise wires go though it. A lot of times you will get a plastic on plastic scraping sound when they go bad.

 

I would check the crank sensor and wiring first, then make sure the truck won't start in Drive.

 

I second this!

 

The lights dimming could be the grid heaters but that should stop after the truck warms up.

 

how do I check The crank sensor?The truck does not crank in drive.please bear with me.I can build 600 hp on an old school big block mopar,but I,m still cutting my teeth on this diesel stuff.

 

Crank sensor is down on top of the crank damper, a little to the right of center. Make sure it's tight and that the gap is somewhere in the neighborhood of 0.050" using a non-ferrous feeler (folded over matchbook cover is close enough if you don't have brass). Then follow the wiring harness up the front of the motor, paying close attention to where the harness goes around the corner of the head. Also check the connector in the harness for corrosion.

If the PCM does not get signal from the crank sensor then it does not know the engine is running. So OD, cruise, A/C compressor, and charging system are not activated.

 

I have the same problem with my 2002 except when i start mine back up it will go into Od and the cruise wont work. I have replaced the APPS and the PCM alone with both speed sensors.

 

Did anyone find a definitive solution for this problem? I lost both cruise and OD as well. any help would be great as I am burning up transmissions. Also I am not getting conv lockup.

 

You wont get lock up unless someone changed the trans to a 47rh instead of the 518.

 

Yeah. the truck came with the 47rh I think. That might make it a true 91. But, this is my third trans I am bolting up. The first two were the orig, and a used. This one has ARI valve body kit and billet conv. I did the jump out the controller behind the glove box to a toggle to get it to OD. But I cant imagine I am just burning up transmissions. The guy who rebuilt the trans I am plugging into it used HD parts for the rebuild and set the bands for a firmer shift. I did everything right. If The toggle switch trick I have is sufficient, I wont press further. But I cant Figure out why I dont feel the lockup before OD. I can really feel it my 98' Feels like a fifth shift. So now that I got the rebiuld info out of the way, The question remains. Is the toggle sufficient or do I need to fix this before I smoke another trans? Thanks