Intermittent Battery Light

PABowhunter · Nov 3, 2015

Pulled out of work yesterday and noticed my battery light flickering on an off. The in dash voltmeter didn't fluctuate at all. The light continued to flicker randomly the whole drive home. I got home and pulled out the multimeter. Had 14.3 volts at each battery and at the alternator. Plugged in AE and it was reading around 12.6 volts with no codes.

It did the same thing today on the way home. I didn't really notice it on the ride into work. It may have flickered once or twice, but it came on several times on the way home.

Both bateries and the alternator are fairly new. No older than two years anyway. I'll have to check my records.

Any trouble areas I should check? Alternator starting to go?

79jasper · Nov 3, 2015

That's alternator almost 99% of the time.

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greyford1979 · Nov 3, 2015

I just had this same thing happen last week. Checked everything like you did, including wiring. Thought there is no way it's my alternator since I had just replaced it in September. I noticed while this was happening my dash lights were a little dim and even my windows went up and down slower. Swapped my brother's known good one on to mine and sure enough, the 2 month old alternator was junk, and it was one from the dealer :doh:

PABowhunter · Nov 3, 2015

Well mine is one from Napa with a lifetime warranty, so I guess I'll be taking it back.

PABowhunter · Nov 3, 2015

Or should I upgrade

Arisley · Nov 3, 2015

Check the big wire coming out of the alternator. Make sure it is tight to the alternator.

Also check to make sure that the connector itself is in good condition. I have seen that connector get almost broken in two and look fine because of the heat shrink on the connector.

greyford1979 · Nov 3, 2015

Arisley said:
Check the big wire coming out of the alternator. Make sure it is tight to the alternator.

Also check to make sure that the connector itself is in good condition. I have seen that connector get almost broken in two and look fine because of the heat shrink on the connector.

Yep that's the main reason why I swapped with my brother since I could't find anything wrong, just to make sure I didn't miss something. Soon as I put mine on his, his light came on.

PABowhunter · Nov 3, 2015

I checked the big wire. it was nice and tight. I'll have to check out the connector a little better.

I may be able to try a swap to troubleshoot this weekend.

Pstrke96 · Nov 3, 2015

If you have a good Napa free swap no ?'s just do it same work as a swap test

Arisley · Nov 4, 2015

I always swap them out in the parking lot. I have a piece of rubber hose I shove over the end of my ratchet, and another piece big enough to shove over the end of the big wire when I pull it off. Don't even bother disconnecting batts. Takes it longer for O'Reilly's to swap it out than it does me.