alternator keeps cutting out

[Jeff Kelderman]

was driving our 03 dually 4x4 show truck to the sema show and the alternator kept cutting out. what happens is the check guages light comes on and the guage goes to the min. setting. if you pull over and shut the truck off, wait 5 seconds or 10, then start it up the alternator starts running again. it may last 100 miles or 100 feet. i stopped in dodge city ks and they put a new alternator on it but it made no difference. since new, (oct 5, 2003) if you let it sit for over a week the battery would be drained. anyone else had any problems like this?

 

[Prairie Dog]

I wonder if your grid heaters are coming on for some reason.

Do you see any other indication of low batt voltage? Maybe it's just the gage acting up?

 

[Jeff Kelderman]

at first i thought it was the guage, but after driving for about 2 hours at night i had to make a very quick exit off the interstate as the voltage got low enough to for things to begin shutting down. i had one dealer tell me the ground was not grounding because of paint under the bolt, but i checked and it is ok. i know another guy here in town that bought an 04 last week and is having the same problem.

 

[Badunit]

Mine did the same thing one time many months ago. I don't know if the alternator actually quit working but the gauge went to zero. I didn't have but a half mile to go till I got home so I didn't notice any actual loss of voltage. It was better the next day and hasn't done it again.

 

[nickleinonen]

might be a good idear to get an ampmeter and put it in for testing [like a 100-0-100 range on it extrenally shunted] it'll show for sure if the alternator is stopping... do these alternators have an external regulator or are they internally regulated?

 

[DPKetchum]

The regulator is the ECM

 

[RonWeiss]

That's right the ECM controls the alternator. And it can shut it down too.



Ron W.

 

[JHardwick]

I made a post about this a couple months back, but couldn't find it.



No Matter.



A few months back my truck did exactly the same thing. Shut it down and refired, everything went back to normal.



Well, last night, a friend of mine was borrowing my truck and she called me no more than a few miles down the road saying "Check Gages" light was on and voltmeter was dropped to the peg.



I told her to shut it down and refire ... ... ... ..... took two attempts to go back to normal.



This morning on my way to work, the "Check Gages" light came on 3 times, and stayed on long enough to see it (not the quick glimpse that is has done a few times in 30K miles), but the voltmeter never waivered.



I checked the wiring last time thinking the service techs may have pinched a wire replacing my alternator bracket, so it's not the wiring... ... ... ... ... ... ... . well, I'm leaving the shop now on a 75 mile round trip delivery to the heat treaters, wish me luck :-laf

 

[ScottBrown]

Check the plug to the ECM , It may need to be disconnected the plugged back in also make sure the ground cable on the battery is tight. $. 02

 

[DPKetchum]

Ecm may have a glitch or alt.

 

[JHardwick]

all connections are good ... ... ... ... I just can't wait til this pig leaves me stranded

 

[rbattelle]

Maybe we should all buy aftermarket external-shunt ammeters?

 

[JLitton]

found this post while searching for an answer to my problem. I am experiencing this problem exactly as described above. It has done it once about two weeks ago and then corrected itself. Today, it has done it every time I have driven my truck and it never gets up to 14 volts on the gauge. If I cycle the key several times or wait a few minutes, the light will go off and the gauge will read about 10 volts but then will eventually drop to nothing. My batteries are starting to lose charge now after dealing with this all day.



What do I need to do to solve my problem other than take it to the dealer?