truck is stuck in limp mode for the trans. started out intermintinly taking a long time to shift, at this time i noticed the indicator light for the gear selector would not would not illuminate. found corroded connections at the ABS controller 14 pin plug. replaced plug and controller. No fix. Took to dealer they could not connect to ABS or PCM modules. and this is what they said, "[I]inspect PCM and ABS module not communicating-no problems but unable to select PCM to access trans, check Pcm connections for corrosion, non found.check ABS system and elec. connectors found moisture in body connector under body door, dried and removed corrosion. check ABS system and now communicating but had fault with left F wheel speed connector. found connector unplugged reconnected, check power and ground to PCM- okay-test bus lines found bad communication with SCI transmit wire, traced wire to poor connection at 60 way connector under dash. recheck and now communication. check 5v reference at PCM and very low voltage only .8v-when other two way connection removed voltage goes to 5v"" When i picked up the truck the truck is still in limp mode as i asked for it back for the weekend . has any one else has common issues ? Where can i get a wiring schmatic for the 5v curcuit ?

 

Do a search on 2003 rams service manual. I just had APPS problems and found a manual online that could be DL'ed. I remember seeing wire diagrams in it. Craig

 

2003 had issue with corosion in PCM connectors. Fix was to install o-rings to prevent water from getting into the connectors and causing corrosion. The only way to check is taking the connectors apart and visually look at connector pins and wires and if corroded the entire harness and PCM will need to be replaced. Good note recalls never expire.

 

Thanks Guys , I'm still fightin with it...

 

Here is a thread from 2005 that talked about the 5V wire that was grounding itself near the A/C unit. Don't know if this will help, but it was in the 5V circuit
and sounds like the same sort of thing.

https://www.dieseltruckresource.com/...893#post804893

Dave