[ManicMechanic]

Hey all, while driving my truck today I got a ding and caught the check gauges light going off. Started watching gauges and the volt gauge was erratic...slowly moving but moving at 14 and higher. Never out of normal, but it got almost to the end of the "normal" range which is abnormal to me. Got to my turn, slowed down to take the turn and it shut off. Tried to restart it and had NO power. Turned the key off and then back on and I had full power, restarted the truck and drove it home...any ideas? Checking it all out now just wanted to see if this was a common thing on these trucks.

 

[ManicMechanic]

Checked everything, no loose connections, even at the ECM. Cleaned all terminal ends. Charging at 14 V for both batteries. Sat and idled fine for 30 minutes. No issues...God I hope this isn't something like an ECM going south.


Edit, also, no codes.

 

[Reledoux]

I had a problem like that with mine and it turned out my battery shorted itself, now I have far more problems lol

 

[bigfish95971]

Check and clean all four battery terminals and go from there looking for shorts.

 

[cumminsdog]

Check all grounds, check the PDC (interior and underhood) cables, Check for AC noise from the alt, Check for corroded battery cables, Check for broken battery cables, Check for cracked battery terminals, Check for loose battery terminals (make sure they arnt turning in the battery)

Buddy of mine had a similar issue. Had a loose terminal in the battery and cracked terminals on the cable.

 

[Junkman]

Put a volt meter in the glove box. You apparently had "power" in the batteries. You need to find where it stopped. Begin studying the wiring diagram to know what is required to run and where you have current with engine on, key to run.

 

[Bryan05]

If everything is tight, batteries are good then take a look at the alternator.

How many miles on the truck? If you are over 100K you might need new brushes in the alternator. If you do replace the brushes, I would put a new voltage regulator on it to. Should be a rebuild kit and it is easy to do.

 

[Off-road]

If everything is tight, batteries are good then take a look at the alternator.

How many miles on the truck? If you are over 100K you might need new brushes in the alternator. If you do replace the brushes, I would put a new voltage regulator on it to. Should be a rebuild kit and it is easy to do.

tmk the typical issue with brushes is in the starter. the alternator typically blows the diodes that rectify the signal.

 

[Anabolic]

check the grounds, I had a problem with mine corroding through.

what about your grid heaters? were they cycling? was the truck warm?

sounds like a grounding issue to me.