Engine/Transmission (1998.5 - 2002) Electrical Problem

[LSchick]

Electrical Problem: 99 3500 24valve, Auto 2x4. Both batteries have drained down to below 1240 V in less than 3 days and of course will not start the truck. Nothing left on. Have had a load check done on the batteries, alt. checked etc. and was informed the batteries are probably going bad as they are 4 years old etc. Due to a time element and appointments replaced the batteries . This hasn't cured the problem ,i now have time and disconnected 1 battery and find i have a severe draw when replacing the 1 post on the 2nd. battery. Have removed all the fuses etc, 1 at a time and find the engine control fuse # 2 seems to eliminate the problem when i remove it. With this fuse removed batteries have stayed at 1270 V for the last 3 days. The truck hasn't been driven in this time. HELP does anyone know what this fuse controls and a possible solution or were to look... ... ?

 

[Midnight]

If no one else responds in time , i will check my shop key tomorrow at work and get back to you.

 

[mopars1]

Fuse #3 (engine control 2) in the PDC (this is from the 2000 model year service manual) feeds the joint connector #2 which in turn feeds to the ECM and the PCM along with the fuel pump relay that powers the fuel injection pump.



The wires from this circuit at the ECM are 18 gauge Red with a White tracer color and it split to cavity #48 and #50.



The wire to the PCM is 14 gauge Red with a White tracer color and goes to cavity 22 of the first connetor.



The wire to the fuel injection pump is a 14 gauge Red with a Light Green tracer color and goes to cavity #7 at the pump.



I don't know if the 1999 wires are the same color, but I don't why they would be changed. Hope this helps you trace the circuits.



You might try and pull the fuel pump relay to start to see if that may be the source.

 

[Midnight]

Mopasr1 is correct. The wiring is the same colours in the 99 as the 00. Good luck.

 

[Oil Burner]

I had the exact same symptoms on my truck. My volt meter was showing a slow draw on the batteries but my alternator checked out just fine. The problem was ( don't know the exact name 'cause I'm at work and can't look at my truck right now) the engine control RELAY (not fuse). I had a painless wiring kit mounted on top of the underhood fuse/relay box and one of the screws was resting on that relay and finally wore through the top and failed it. I would check that first as it might be an easy fix. Good Luck.

-Jason

 

[LSchick]

My thanks. I do appreciate the answers,have replaced the pump relay with the head lite relay as they appear to have the same part numbers . Reinstalled the engine control fuse late last nite and the voltage was down to 1250 again this A. M. Have charged the batteries, driven the truck parked for the nite, and again removed the engine control fuse Voltage reading was 1285and will see what the reading is again in the A. M. Again my thanks as the help and advise is appreciated.

 

[PMalin]

I find that fuse #2 30A fuse, goes to the "ignition switch". However, if you are saying there is a current draw while the switch is turned off, then it may be your "ignition switch" is going bad?? It may have a stuck contact, feeding one of various circuits? Either Run, Run Start, Run Acc. Some of these you may be able to eliminate right off. Since the starter is not cranking continuously you could probably eliminate that. Run and Run Start conditions also feed Fuse 9 10A in Junction Block and power the ECM and PCM. But again with the switch off, I would think they should be without power. I do not know for sure how accurate this info will be for you, but thought I would have a quick look at some possibilities.

Good Luck

 

[LSchick]

Thanks again for the input on this electrical problem, I took the truck in to a dealer yesterday to have a exhaust manifold replaced under warranty that was cracked, mentioned the electrical problem and had them look at it. They had 2 of there techs check it out. Said my theory on the engine control fuse was wrong and explained why which i now believe and understand. All 99. s have a seat belt module under the drivers seat that stays on for 30 minutes after you shut the engine off,this apparently has been a problem ( Mine checked out fine as most have to be replaced ) They checked this out with Chrysler who stated there is a new T. S. B. now out stating that if the truck is idle for 3 days a fuse on the 99. s should be pulled to cure this problem, this the I O D fuse in the side dash panel. I really believe this dealer Bell Dodge in Phoenix Arizona is excellent as 2 years ago when i had a serious problem they were the only ones who took an interest and helped and solved the problem. (by the way I'm not from Arizona and didn't buy the truck from them, am only a winter visitor) will keep you posted after i try this for a few days but doesn't sound like we have advanced much over the years. Again sincere thanks.