Charging system failure

SarahsGMC · May 17, 2015

My 06 sierra half ton with the 5.3 is throwing a charging system failure message and the battery gauge is right between 9 and 14 at about 11-12. I just put a brand new battery and alternator in both bigger than stock Because it threw this message before and it was time for an upgrade.. all grounds are good and cleaned wires are tight.. I can't figure it out.. haven't had the alternator tested yet. I put the battery in first and got the alt a couple weeks later when I installed the alternator it cleared the message and I thought all was good, but since I put this one in my lights inside the truck and my tail lights will flicker while idling with the speed of the belt... been doing this since the day I put it in and last night I get a voltage drop battery light and the message. Any ideas?

MikeNH · May 17, 2015

Probably a faulty alternator. New doesn't make good- it took three from advance auto to get a working one in my Jimmy. lol

&CDFiXER% · May 17, 2015

Probably a faulty alternator. New doesn't make good- it took three from advance auto to get a working one in my Jimmy. lol

+1 on checking the 'new' alternator. I have had the above happen as well, only it was the first one was bad and the second one was good, probably because THEN and only then do I remember to have the dang things tested BEFORE I leave, lol. Has happened at three different parts suppliers over the years.

DanMan_S · May 17, 2015

On my '09, turned out to be the fusible link on the firewall. It was loose and vibrating around. When I cleaned it up, cleaned the corrosion off and used dielectric grease on the contacting surfaces and tightened it up, I stopped getting the error message.

SarahsGMC · May 18, 2015

Ended up being a bad alternator started smelling like chlorine and had it tested at 2 different places it failed both. Got it warranteed and new one is good.