Engine/Transmission (1998.5 - 2002) Random voltage drop

[KMahnke]

I'm having a problem on the '01 with a random voltage drop. This just started happening within the past 3 days. Truck cranks good, no signs of a weak battery, but sometimes after driving I'll get a check gages light and the volt meter will drop all the way to 8. I can turn the truck off and crank it right back up and the meter will read normal, and it wont do it again until later in the day. Sometimes the voltage will just drop and read between 14 and 8. Checked for codes and it threw a 1682 and 1693.



P1682 (G) Charging System Voltage Too Low Battery voltage sense input below target charging voltage

during engine operation and no significant change in

voltage detected during active test of generator output

circuit.



P1693 (M) DTC Detected in PCM/ECM or DTC





Has my PCM gone kaput? Or is this an alternator problem? Any help appreciated,



Thanks!

 

[MHagen]

It is most likely the Alternator. I had the same thing happen a few months ago.



Mike

 

[KMahnke]

Thanks for the reply, do you know where I can get an alternator??? online someplace maybe just to compare prices. I tried to get the darn thing tested at 2 different NAPAs and they couldn't figure out how to hook it up or they "didnt have the right wires" to hook this one up. They say they can order one for $223. Another place I always go to doesn't even stock them. The advanced auto and autozones are even worse so I dont even go there unless i need tire shine... .

 

[WTBurke]

Hey KM,

Check out

21 SI Alternators, 22 SI Alternators, Large Truck Alternators, Caterpillar Alternators, 21-SI Alternators, 22-SI Alternators, 21SI Alternators, 22SI Alternators



William

 

[Moose Truck]

I'm having a problem on the '01 with a random voltage drop. This just started happening within the past 3 days. Truck cranks good, no signs of a weak battery, but sometimes after driving I'll get a check gages light and the volt meter will drop all the way to 8. I can turn the truck off and crank it right back up and the meter will read normal, and it wont do it again until later in the day. Sometimes the voltage will just drop and read between 14 and 8. Checked for codes and it threw a 1682 and 1693.



P1682 (G) Charging System Voltage Too Low Battery voltage sense input below target charging voltage

during engine operation and no significant change in

voltage detected during active test of generator output

circuit.



P1693 (M) DTC Detected in PCM/ECM or DTC





Has my PCM gone kaput? Or is this an alternator problem? Any help appreciated,



Thanks!

What was the outcome? My Truck just started this 01Sep08, Thanks MooseOo.

 

[SSolderitch]

voltage regulator in pcm bad? hook an external one to see if the problem continues... . cheaper than an alt.

 

[Moose Truck]

The strange thing is, the head and instrument lights are nice and bright, with the volt meter on the 8 Volt peg Tomorrow, I am taking the VOM w/ me to work, I'll take her volts and see what's up. IDK, maybe there is a bad wire to the PCM??? Moose

 

[DodgeWarlock]

Recently had the exact same problem on our 01. After circling my tail for a while worried it was the pcm, it turned out to just be alternator failure. (Did not notice if you had an automatic, but electrical noise from our failing alternator made our convertor lock and unlock at about 45mph repetitively before it failed. )



Try Rockauto.com or try another Napa. Got mine at Napa for a good bit better price than that. The Bosch and the Nippondenso are interchangeable, just make sure you get the correct amperage unit.

 

[Moose Truck]

I had the Auto thing a couple of years ago, Fixed with Sheilding the alternator ground, and by putting in a DTT Noise Filter. Did both at the same time however, don't know which fixed what?

I did not have a problem on the way to work, as I had brought the Digi- VOM. NAPA for the Alternator sounds like a good Idea. Regards, Moose

 

[DFerverda]

Mine just conked out yesterday. Was 30 miles from home, check gauge light came on, volt meter read about 10 volts, made the mistake of shutting the truck off on the last stop and had to jump it.
Alternator was bad. I replaced with this one, works fine now.

Alternator by Remy New - Part 15580002 - Advance Auto Parts

I would have liked to upgrade to Mean Green or such, but a couple hundred bucks difference right now is out.
Dirk