Tbopp

Hey guys. I got a new battery and alternator, but it still won't charge. Left lights on for a cpl hours. Plus I could get a jump for a few hrs and the alarm kept going off. No sound because it was dead but light barely flickering. So replaced both of them things. Still won't go past 12.0 volts on multimeter. Is there a fuse or relay I should check? I checked all the small ones inside the car. All working ?

donbrew

12 volts engine on or engine off? Model, year, mileage?

Tbopp

12.44 off and when I start it goes to 12 the decrease very slowly. 2011 chevy hhr

RJ_RS_SS_350

Battery cable terminals break, connections get loose or corroded. 12 volts measured at the battery is a dead or damaged battery.

Tbopp

I'm worried that advance auto sold me a defective alternator. Can you test it at the alternator while it's running with a multimeter? Shouldn't it read something if you place it on positive bolt of alternator and ground anywhere?

RJ_RS_SS_350

Are you measuring at the battery or under the hood? 12.44 is a dead battery too.

Tbopp

Had the battery tested at the shop I bought it from. Read 12.6. But I've started it up a few times to check it. So it's gone down to 12 .4. But with car running goes down to 12 now. It's not charging

Tbopp

I'm measuring at the battery in the rear. Going to get it charged at the AutoZone later. And try again I suppose. Check connection at the alternator again. But I don't know if there's fuses or relays that could of gone bad

donbrew

Sounds like a defective/incorrectly installed alternator. Engine running a VOM at the battery should read somewhere around 14 volts. No fuses I can think of. Sometimes wire get compromised.

The large red wire should connect the alternator and the starter then to the fuse box then to the battery, Some cars may have a fusible link between the alternator and the starter; check it for continuity.

Tbopp

Thanks how do you check for continuity?