Hi All,

Sorry if I posted in the wrong category...I'm a newbie if you couldn't tell!

Anyways. Let me start from the top... My truck is a 2001 Dodge Ram 1500, V6, 2 wheel. We had it parked in the garage for the winter, and to my dismay, I have seen signs of a mouse in the cab...my floor mats were chewed. It was parked since late last summer, because I thought the water pump was going bad, after I just had a new radiator put in, and would deal with the it the next summer, seeing as how winter was coming. Well, we got the truck out in March and it did need a jump (I know, shame on me for not starting it over the winter) But it started right up after about 10 mins on a jump. It did have a slight weak start, but it was running fine, and it the waterpump issue went away. Anyway. I had been driving it a few times with no problems, until I was driving to town one night and noticed that my dash lights and headlights seemed to be dimming a litte. Well I didn't think anything of it until a mile or two down the road, my check guages light came on and I saw the voltage gauge and spiked all the way up. So I pulled over, shut it off, and it started right up. I drove it home and it did it 2 more times. Well the day after or so, I get in, and drive it and it has no problems. But the next day, it did the same thing...and when I shut it off it won't start back up until a few minutes. When it finally does, the clock on the radio resets. So, I checked the battery cables-all was good. And so I checked the alternator by taking the bat. cable off-and the truck still ran. (Which I now know that is a no-no to do if your truck has a PCM). So I replaced that battery, and it seemed fine the next two drives. I went to drive it today, and it spiked again before I could get 5 miles down the road. So I pulled over, shut it off, and I noticed the voltage guage was still up. So I waited and waited and it wouldn't start. Well when I opened my door, the guage went immediatly down and it started up. So I drove it home. I personally thought it was the voltage regulator. So I took the other truck to Autozone, and the guys there said it could be the voltage regulator and that its in the PCM. :/ I couldn't get it scanned anywhere becuase no one is open on a Saturday around here. I did try to pull the code with the ignition, and it came back P DoNe...which I looked up and it meant that no codes were found. The guys at autozone said that I may be able to piggyback in a external voltage regulator, if thats the problem. So my question is, what could it be, and if it is the voltage regulator, how could I go about piggybacking an external one?

Any help would be great!

Thanks
-Dan

 

It's time to check connections and continuity in the charging system -- you've got either a punked regulator or an intermittent open or short circuit. A short to ground on the alternator field winding will turn the alternator hard on all the time; an open (or high resistance) in the sense circuit will cause the PCM to see low or no battery voltage and ground the field winding to crank the alternator up.

Grab the factory service manual (in the 2nd gen Ram FAQ section) and check all of the wiring shown in section 8W-20, and wiggle the wires/harness while checking.

If the regulator is actually failed, the economical and more reliable fix is to engineer in a two wire external regulator from an older Chrysler product. There are how-tos scattered around the web, just a google away.

Welcome to DF!

 

Okay, so this is my first vehicle and other than routine maintaince, I'm pretty much in the dark. So, I should wiggle the wires in the diagram while the truck is running? And if the volt gauge spikes, then its that wire I wiggled? Right? And if it doesn't do this afterwards, then it would most likely be the EVR? Right?

 

The wires to the alternator (except the feed wire to the battery) are all ecapsulated in some plastic thingy.... What you may want to do, is disconnect the battery, take that thing off the alt, clean all the terminals on the alt, and the plastic thing, and put it back together. Also do the battery feed wire. See if that doesn't improve its attitude any.

 

Ok. Everything at the battery end is clean. I don't think the alternator is dirty, but I'll double check.

My uncle suggested that since a mouse got in the cab, that he could have chewed on a wire causing a short which is responsible for the voltage spikes. Is this a possibility, and if so, where under the dash might we look? I looked under the dash briefly, and didn't notice any obvious spots, but that dosen't mean it couldn't be a spot hidden to me. Not sure if theres a particluar place I should be looking... I've wiggled some wires under the hood, while the truck was running, and no spike.

Thanks.

 

So I've wiggled every wire I could get my hands on while the truck was running. No spikes. I'm really stumped on this. I heard that if it was the actual alternator that the gauge would be showing a low charge, instead of spiking up to max...But right now I'm clueless. Any other suggestions?

 

No -- allowing the voltage to skyrocket like that is tough on the electronics and battery, and might cost you a helluva lot more than you want to spend in both time and money. With the battery disconnected, use a multimeter to check resistance -- not continuity, but actual resistance which should not vary as you wiggle the wires. You'll want to wiggle the wires at every point along their runs, as it's not a valid test if you wiggle an end and don't impart motion where there's a break in the middle.

If you're not comfy with electrical testing, tow the truck to an automotive electric shop and let them hunt it down. Or find some web site somewhere that might teach you what you need to know. But don't run the thing until you're pretty darn certain you've found and corrected the problem.

Whoever told you that doesn't understand automotive charging systems.

 

Ok... I see what I can do. And if I can't do it, then I'll leave it until I can get someone who can. And I know this is sort of off topic from the wires, but I was wondering from something I read, could the alternator in my 01 possibly have a fuse somewhere that it connects to the alt.?

 

Yep. It's in the PDC, should be 140A.

 

I just wanted to say that I've recently had similiar issues with my 01 Ram 5.9L quad cab 1500 2wd. I took the Negative cable and pulled it back off the motor and zip tied it to the metal brake lines by the PDC box on the right side of engine compartment. Then once my repairs were finished I placed it back down on the motor and attached it to the spots I thought it was attached to before? I thought? lol And now when I connect the battery it blows that 140 amp fuse in the PDC marked Alternator?
I went to Dodge bought 3 of them thingy's and was told that my short is that I'm grounding a hot wire somewhere? or grounding something that shouldn't be grounded? When I read the manual I've got it says that the negative cable connects to the back of power steering pump but leaves out the area on the right side of my support bracket and the steer/pump that another cable grounds to that runs down my valley between the intake a right valve cover. So my question is I don't think my truck had the neg. cable grounded to back of the steer/pump and I put that part of the neg. cable with the other one that grounds between the support bracket and my steer/pump? Could that be the reason I'm shorting out? Having the 2 grounds over lapping each other and mounted together with nothing seperating them? Can anyone send me a diagram link for the whole negative cable from the battery to the alternator? PLEASE!!!!!!!! and thank you!!!!!!!!!!!!!!!!!!!!!!!!!!!!