Electrical issues with 02 chev 'burb

[ak77]

Hello everyone
I'm looking for some collective wisdom here. I have an '02 Chev suburban, and all out of the sudden it had developed an electrical issue, in particular the battery stopped charging.
Here's the timeline...
Mid July drove down south for work, round trips to the rig for about a week averaging 100 km a day - no problems. On my way back about half way in the battery light came on, the charging gauge was at 12v. Made it back home by the skin of my teeth. Pulled the alternator out, had it bench tested at the crappy tire - all good. Changed the battery under the warranty just for poops and giggles. Started the truck and the charge gauge still showed low charge, only 12v on the terminals. Noticed the terminal bolts were a little wobbly, but couldn't make them tight as heads were rounded. Decided to buy a new pair, installed them - full charge on the terminals... So i thought - great. Parked it, left for work for a month (fly-in). Came back, starts no problems, drove for 2 days no issues... Parked it last night, hopped in about 24 hours later today - battery light is on, 12v on charging gauge. Wtf??? Terminals still tight. Only additional device to draw power that i plugged in yesterday was the dash cam I've had for years, it's not hardwired, runs off sig lighter plug. Never had an issue before leaving it plugged overnight, though i have had forgotten to unplug it in the past leaving for extended periods of time, draining the battery completely. As i says i have changed the battery since...

I did check the fuses but not overly thoroughly, what i saw was fine.

Just pulled the battery out, took home, put it on the charger... Should be back to 100% by the morning...


Provided CT didn't mess up there bench test and my alternator is good, seems like the issue is getting the charge from it to the battery.
Anyone has any other suggestions to what i need to check?
TIA

[Suzukisam]

Test the voltage at back of alternator while running if it’s higher then battery then wire from alt to battery has an issue. If it is at 12 volts like battery alternator is bad. CT did not screw up the removing of it and installing bounced the worn brushes giving temporary contact. Replace alt:

[Rustynail21]

I would suggest checking grounds and tracing the wires, especially the power wire off the back of the alternator. Check the connectors that wire goes through thoroughly. There has been reports of battery cables on chevy's breaking down internally, might be worth taking a look.

I have been exactly where you were on a dodge van 20 years ago and it turned out to be the main connector was slowly going and one by one electrical gremlins popped up until the alternator stopped charging. Could also be a break in the wire, so trace it carefully and look for damage!

It'll take some time, but chances are you'll find it! I went to 4 shops before one realized that the harder they pushed with the test light the more volts we got!

Good luck and keep us posted!

[does it ALL outdoors]

Originally Posted by Rustynail21

I would suggest checking grounds and tracing the wires, especially the power wire off the back of the alternator.

That's also where I would start looking, especially the ground side of things.

Good luck.