diesel_diva26

We just recently discovered that my 93 dodge 250 has an overdrive tranny. Whoever owned it before has made it a wiring nightmare. When I first got the truck I had a switch for everything from my alternator to my break lights. It was a mess. Does anybody have the wiring schematics for my transmission? It's a 46rh.

diesel_diva26

Also, anybody know if my trannys a lock up? I'm still fairly new at this, so thanks for the help!

SNOWMAN99

Lock up was not used until the 1994 model year trucks. That is the biggest EDIT with my truck. A Goerend converter did help, but I can still tell its there. Maybe a 5spd conversion is up for me.............

diesel_diva26

Well that sucks. I was considering converting to a 5spd but I've never been a big fan of manual trannys. is there a way to make mine lock up? or would it even be worth all the trouble?

Tater93

You have to convert to a 47rh to have lock~up. Its becoming a pretty popular swap, and there are plenty of guys on here that have done it. I'm sure they'll chime in with some advice.

dzl_damon

There were some wiring schematics in the Sticky from the factory service manual. I HIGHLY suggest getting a FSM, well worth the $40. Don't waste your $20 on Chilton or Haynes.

If your OD is not working, there is a common problem with the Throttle Position Sensor (TPS). For $12 you can make your own, and adjust shift points with yet another **** on your dash! But usually you mark 2 settings. Normal OD engagement, and towing OD engagement. A fellow here sells a "kit" for $30 or something if you don't feel like going to Radio Shack and getting it yourself. A write up for this is also in the sticky.

The previous owner of my truck did a nightmare of rewiring as well. I feel your pain brother. I'm just finishing up my rewiring now.... lets see if she works!!

Here we go:

'91.5 wiring diagrams
http://dens-site.net/Dodge_CTD/1991.5-Wiring_Diagrams/

TPS adjustment:
http://www.pdrdiesel.com/oldsite/Tech1GTPS.htm
http://dens-site.net/Dodge_CTD/tps-adjust.jpg

Replacing the TPS with a potentiometer:
https://www.dieseltruckresource.com/d...ad.php?t=42003
Another writeup, but with pics:
https://www.dieseltruckresource.com/d...d.php?t=142641

wannadiesel

Also see:
https://www.dieseltruckresource.com/...77&postcount=2

If the PCM is totally whacked, here is a low-cost easy alternative.
https://www.dieseltruckresource.com/....html?t=156988

diesel_diva26

Is the wiring on a 91.5 the same as a 93?

archer39

yes

diesel_diva26

I'm pretty sure the problem is my PCM. We ended up grounding out the wire for my overdrive and now i just have a switch in the cab and it works great. the pcm doesnt do anything else important does it?

Crossy's son

the PCM controls your whole charging system and A/C system....no pcm= no charge..unless you do other things.

diesel_diva26

Well apparently my PCM hasn't been working since i bought the truck 4 months ago and we just rewired some things here and there. It's not hurting anything now, that i know of, and i dont want to spend the money to fix it unless necessary.

Crossy's son

and cruise control too. i think

wannadiesel

No, they are very different!

The thread that the individual post I linked to explains the differences.

The problem with your truck is most likely related to the crank speed sensor. Your PCM is not getting a signal from that sensor so it does not know the engine is running. No need for A/C, OD, or a charging system if the engine is shut off...