boomer

??? I'm the proud owner of a 93/D350, auto w/od, 354 rear. This truck and I have seen 1,012,000 miles together and it still looks good!! Problem is : power windows and H/AC quit functioning, OD lockout quit working, all at the same time. When pushing switch for any of the afore mentioned items, the Command Center all lights up, (Brake, Water in Fuel, Wait to start lights). Checked all wires and relays. Is this a grounding problem or a PCM malfunction??

bigredbrick

I doubt that the power windows are 'puter controlled, same with the heater and AC. No fuses are blowing? I just ordered a ECM to hopefully correct my problems- intermittant voltage drop and tach not working. How many times have you rebuilt the trans.?<br>Chris

boomer

The tranny's been rebuilt each 400,000 miles. The overdrive unit exploded once at 400,000 so I don't take chances now. :<br>I'm getting intermittent flashing water in fuel, wait to start and check engine lights now each time I let off the accelerator. The battery tests 14.05 volts! It's charging 14.47 volts. I spliced into a smaller wire in the fuse block to feed the window and heater/AC and the windows and heater are working but no AC. The Larger Blk/Pk wire that normally feeds the windows and htr/ac is hot but won't operate either????? I'm thinking mabe an amperage drop from the PCM???? After more than a million miles in this truck, I thought I'd seen everything but this one's got me scratching my head!!!

Lil Dog

A common failure point is the Crank Sensor on the front of the engine just below the fan hub.. This will tell the computer that everything is running and close the ASD relay that will operate some of that auxiliary stuff.<br><br>I would start there before spending $$ on the PCM..<br><br>J-eh

boomer

Ran a diagnostic scan on the PCM this morning. Only thing to code was the TPS. PCM seemed fine?? The OD is hot wired but not by bypassing the TPS. Going to change that by cutting the orange/green stripe wire near the PCM connector and grounding it thru a toggle switch. This will eliminate the TPS from the OD system. Going to change the ignition switch tomorrow and go from there?? It's crazy!!!

greatwhite

If it is your PCM, and I think it sounds more like grounds, I have a spare used one which fits 92 or 93 models w/auto trans. Only available new or from wrecker. New one is $1100 CDN. No jobber part available for trucks with auto. On mine it was a broken wire at the plug where the wire passes through the clip at the top of the head. But except a/c all other accessories kept working. No speedo cruise O/D charge or a/c. Computer didn't know engine was running so it wouldn't turn these on. Rick

Dieselbuilder

Here is a shot in the dark , check your ground to the body of the truck?

boomer

Thanks guys. I have a new PCM setting at the parts store waiting for me to pick it up. I just want to cover all the other bases before turning loose the cash for the PCM. As for the body grounds, I ran additional grounds to the firewall more than a week ago. I get good continutity from the negitive post of the battery to the body, steering post &amp; motor. I disconnected the intake air heater solenoids and no more flashing lights on the dash!! Guess that was in the intake air temp sensor system, (which goes to the PCM!) I'm still not convinced that the whole problem isn't within the PCM????? Maybe it's a part time PCM and a part time Pain in the #$%^*?????? Too many different problems all at the same time and all monitored by the (You guessed it) PCM.

Farmall

[quote author=greatwhite link=board=9;threadid=13763;start=0#130434 date=1051015467]<br>If it is your PCM, and I think it sounds more like grounds, I have a spare used one which fits 92 or 93 models w/auto trans. Only available new or from wrecker. New one is $1100 CDN. No jobber part available for trucks with auto. On mine it was a broken wire at the plug where the wire passes through the clip at the top of the head. But except a/c all other accessories kept working. No speedo cruise O/D charge or a/c. Computer didn't know engine was running so it wouldn't turn these on. Rick<br>[/quote]<br><br>Not sure about in Canada, but here in the states you can get the comp from several pasrts sources. I ended up getting mine a Autozone for $189, I also found them at 3 other places, but they had to special order them and it would take a week. Autozone only took one day. And my truck is a 92' with a Auto. Bill

boomer

New PCM from the local Dodge Dealer is $752.00 + Tax. Reman not available from Dodge. Not available from NAPA either! Found 1 available from Advance Auto for $337.00. :'(

boomer

;D ;D ;D ;D ;D ;D ;D ;D ;D Well, Sports Fans, The resolution to the mystery is at hand!! The answer to the question; Grounding or PCM has been answered. It was neither!! It was the ignition switch!!!! A $57.00 part!! Changed the switch andf all the problems went away!! YEEEE-HAAAA!!!!

bigredbrick

Hallelujah!! If only I could solve my electrical woes. :'(<br><br>Chris