Hello all,
MY 01, 2500, Quad, auto, has a problem! The guages go crazy, like the full tank of fuel goes to empty low fuel alarm comes on, the speedo goes to zero when traveling at whatever speed, the temp gauge goed to zero no matter how long it's been driven! Hope you get the piture. I also get a no bus in the odo. Now this can all take place in the matter of seconds! Went to the dealer of course he said bad computer- 800.00. This all happens, it seems, when it's cold! I saw on another post from way back that it 's a corroded ground, foundit cleaned it.... but it still happened this morning. Any ideas?

 

You can check the connection between the dash and the pcm,
might just be loose enough that cold shrinks it just enough to lose connection.

Bad part, I don't know where this connection is.


phox

 

clean the battery cables well, wierd things happen in the electronics if the ground path gets resisted

GREG

 

I spent weeks tracking down something similar, turned out the female connectors on the pcm harness behind the airbox were stretched out making poor contact. First thought was bad pcm also, but when trading the pcm to another rig it worked perfect. Solution was to take the connector apart and squeeze the connectors shut a little bit.

 

What connection between the dash and pcm? I've checked, cleaned, and greased every connection I can find!
I don't see how to take apart the connectors? They look like they are one piece....
I don't think this PCM is bad because it's so random. I also want t o prove the cocky service manager wrong ..... Thanks for the help!

 

Any more ideas? I've looked on here for anything close to my problem, I can't seem to find anything.....

 

The connector I'm talking about is right on the pcm and is held together by one bolt.
Here's instructions for a older rig, not sure if they apply or not to yours
http://dodgeram.info/tsb/1997/08-01-97.htm

Take care with the grease, a computer signal can jump between contacts causing many different problems if the grease is bridging between contacts on the non pin part of the connector. I usually smear the dielelectric grease on so it enters the female cavities then clean off the grease that isn't in the cavity with an electronic cleaner soaked rag. Too much down in the cavity can also push out when you put the connector together and short the pins together.
No big deal on 12 volt signals but with the low voltage computer signals can cause a haywire condition that's very difficult to diagnose.