I just got off the highway and had a wire short out in the bed of my truck and completely drain the batteries to the point where everything in the truck shut off and it came to a halt in the ditch. I found the problem, jump started my truck and when I did, the alternator gauge started showing a charge of about 11 or 12. I figured I could drive another 30 miles at highway speeds and charge up the batteries. The guage stayed at 11 or 12 for about 5 miles then it dropped back to completely dead. I drove the truck back home, about 12 miles, and it still runs, the alternator just won't charge.

Think I ruined the alternator? A guy just told me that when he discarged his completely, the dealer had to RESET THE COMPUTER something or another to get the alternator to charge again. IS THIS TRUE? Please help. That sounds like the biggest bunch of malarky I have ever heard.

I tried searching for previous threads, but got real tired of waiting 30 seconds between searches.

Thanks for any help! And don't look at my job title. You'd think I would have had a fuse on it.

JWB

 

No, there is no reset procedure. Charge up the batteries, then test the main charge fuse in the PDC. It may have blown. Other than that, the alternator may be toast.

 

I just check the main charge fuse labeled "Alternator 140 amp" in the PDC. All is good there. I guess an alternator from NAPA for $128 is good enough? Should I get one from DC? Of course my deal in town is closed today, service anyhow, losers.

Thanks for the tip. Any others before I jerk the alternator and have it tested?

JWB

 

not sur eon the 03, our fleet truck w / cummins had 2 fuses under the hood that you could find by following the lead from the alternator, if they go, she no wanna charge even with a fresh altynator........

 

I'm going under the assumption that the batteries are so dead, and pull such a load on the alternator, that it won't ever charge until I charge the batteries up to a decent level where that alternator can actually put energy back into them. May not be true, but at this point, that is what I think. If the old lady ever gets back here with my battery charger, I'm going to try that. I hate living here and building there. Everything I need here is there and everything I need there is here.

Thanks, JWB

 

Some of the do it your self parts house can test the alt. [ while in truck ] free ,
make sure its bad before you replace it , the regulator is in the computor .
Do you know where the wire that shorted went to ?

 

Definitely charge the batteries before you replace anything. You may not be getting enough power to the pcm to power it up and tell the alternator the batteries need charging.

 

I had a power cable lying in the bed of the truck that I connected my elec/hydraulic cherry picker to (see gallery). It went straight to my battery (brilliant, I know) with no fuse. After pulling a water pump up out of Lake Keystone with my chains, I just threw them in the back of the truck. Before I got home, the chains had moved around enough to get in between the insulation on the live connector in the truck bed and shorted out my batteries. It welded my 3/8 transport grade chain to the bed of my truck and completely killed everything. I charged my batteries for an hour and everyting is good. No money spent on this stupid misktake. A large fuse is in the future.

Thank you guys for your input.

 

Nobody on this site ever does anything silly like that!