Low voltage diagnostics

[silverscottsk10]

On way to Yamaha to pick up some parts my 06 Silverado popped up a charging system failure, voltage started dropping, picked up my part and headed to o'Reilly's, hooked it to scanner and showed no issues, but as it sat and idled it went back to 14.8 on dash but my radar scanner reads voltage and showed 13.8, on way home voltage dropped to 10.2 volts, all connections are right, belt is good no slipping, there's an odd smell coming from under hood, not quite a burnt electrical smell, but close, I'm thinking its alternator, anyone else have any thoughts or things I could check before I drop 100$ on an alternator?

 

[Camar068]

As usual, check all your grounds and battery connections. Maybe put a meter on it with no accessories running. Then start turning things on. Try to catch a reading when the radiator fan kicks in. Make note of what was turned on if/when you see the low voltage.

Turn everything else back off, and turn that one suspect accessory back on and see if it does the same thing. If it doesn't, then it would seem it's a charging/battery circuit issue.

Just a few things I'd do in that situation. Let us know what you find.

My current battery went dead a while back. I didn't see any corrosion, and had 14.5 running at the battery. The post were dark grey in color. So I jump it and run it down to where I got my battery from (still under warranty). It tested fine with 2 testers. They sanded the post to where they were shiny, bam problem fixed.

 

[silverscottsk10]

Everything is good, I don't have any draws on it, just charges and then won't

 

[silverscottsk10]

Alternator is bad, failed testing three times, at 150$ this one should last another 160k miles

 

[HotRodPC]

Alternator is bad, failed testing three times, at 150$ this one should last another 160k miles

Don't count on it. It seems the OEM factory alternators will go for a long time, then once replaced with a reman, then they're good for about a year just like clock work. If you got a lifetime reman, plan on exchanging it about every year. I'd almost rather just go to a Chevy dealer and buy a brand new AC Deloc or Delphi and be done. Delphi is gone now so it'll probably be an AC Delco. Not sure how true but I've heard even GM is using Bosch alternators now.

 

[Camar068]

Don't forget we get 5% off at Rockauto.

[edit] lol had starter on the brain. DB Electric has alternators as well.

https://www.dbelectrical.com/alternators/automotive/chevrolet/c-k-r-v/5-3-liter/

 

[silverscottsk10]

Don't count on it. It seems the OEM factory alternators will go for a long time, then once replaced with a reman, then they're good for about a year just like clock work. If you got a lifetime reman, plan on exchanging it about every year. I'd almost rather just go to a Chevy dealer and buy a brand new AC Deloc or Delphi and be done. Delphi is gone now so it'll probably be an AC Delco. Not sure how true but I've heard even GM is using Bosch alternators now.

I'm thinking about trading this truck in, if I'm gonna have to work on it every weekend I might as well get a diesel