i asked my brother to swap the battery in my truck (94 Ram 5.2), he crossed the cables, - to + and + to-. tried starting the truck with the cables crossed didn't work so he called me over. i corrected the cables started the truck (ran fine) then noticed my alternator wasn't generating the correct voltage. i replaced the alternator. didn't fix the problem. later i learned the voltage regulator is in the PCM so i decided to replace that. got one from a junk yard plugged it in and the truck runs like $#!t. all fuses and relays are good. oh, and still not the correct voltage. what can be the problem ?

 

How did you check to make sure that the fuse's and relay's were good? I'd think that they'd blow once you cross the positive and negative.

 

i pulled every single one (inside and outside the truck) out and checked. i purchased a service manual to check the relays correctly.

 

I think you may have to have the pcm flashed to your vin for it to run right

 

so after the cross, it started and ran fine, with only one problem, no charging, likely due to a blown out voltage regulator in the pcm.

with second pcm, its still not charging, plus - its running like ****, whatever that means.

so did the replacement pcm come out of the same year and model of truck, especially -
year 94 or maybe 95.
5.2 gasser. not 5.9 gas, nor diesel.
california emissions. assuming yours is cali.

describe what running like **** means. rich? lean? skipping? black smoke?
also, check the main fusible link? thingy and the IOD, and all the other big large fuses in the PDC box beside battery.

 

i would say skipping is the best way to describe it. all the fuses are good, a buddy pulled the pcm for me. i begged him to be sure to pull it out of a 94-95 and specifically the 5.2, i think that is were my problem is. and I'm in miami, FL. idk if that makes a diff as far as emissions goes. but why wasn't i getting the correct voltage ?

 

any idea what that will cost me ?

 

If it were mine to do, I'd put the original PCM back and engineer in an external voltage regulator. Any two wire solid state regulator from any older Chrysler product will do, and there are howtos scattered around the web that'll tell you how to do it.

 

haha ! i was planning on doing that next if i couldn't get everything to work properly.

 

vin number in the pcm doesn't make any difference. but the engine size does.

oops, i looked at J415's signature.....
the california emissions (at least in later years) had O2 sensors on both sides, whereas (again in later years), the federal emissions had on one precat O2.
never mind on that one.

the 5.9 V8 or 3.? V6 would have different fuel delivery rates. if you don't have a 5.2 pcm, it could be a problem.