2008 Sorento LX charging system problem

General
1

Hey guys,

2008 BL V6 Sorento with 224K miles, likely with a replacement engine that has fewer miles.

Yesterday, I got the usual battery and brake system warning lights immediately after heavy acceleration while merging. Not sure if they’re related, but it was definitely unusual.

About 15 months ago, I replaced the battery and alternator for the same issue, and they’ve been working fine until now.

Had them tested at a parts store today, but no problems were found.

The warning lights are intermittent and usually disappear above 2000 RPM. My OBD reader shows the voltage fluctuating—12V at low idle, 13.8V while driving, and sometimes 13.8V at idle. The warning lights only come on when the voltage drops low.

The car starts and runs fine for now.

I removed and reinstalled the battery today, tightening all connections, but it didn’t help.

The car has a history of valve cover oil leaks, but those were fixed before the issue 15 months ago. There might be some minor seepage, but nothing significant.

Any ideas on what else to check?

Could it be broken grounds? I’m stumped.

Thanks.

1 Like
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Given the issues with fluctuating voltage and warning lights, you might want to recheck the battery connections and grounds for corrosion or looseness. Also, consider looking at the voltage regulator and the alternator belt. If the problem persists, a mechanic with electrical expertise might be the next step.

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In a 2008 Sorento LX, a charging system issue could be due to a failing ECM, which can prevent the alternator from charging properly. If you’ve already checked all grounds and connections, the next step is to diagnose the ECM to see if it’s causing the problem.