battery light on

2007 JEEP WRANGLER
150,000 MILES • 3.8L • V6 • 4WD • AUTOMATIC
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JU02MA28
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  • 1 POST
I have a new battery and new alternator and the battery light still on and battery is not charging.
Apr 3, 2020 at 10:09 AM
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KASEKENNY
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We need to inspect the voltage regulator circuit. This is what controls the alternator charging circuit. So the light coming on shows the voltage is too low. If the alternator is ok and the battery is new then we need to suspect the PCM is not commanding the alternator on to charge the system.

The only way to do this is monitor the PCM data with a scan tool. You can check for voltage on this circuit but that is misleading. We need to see what the PCM is commanding it to do. Let me know if you have a scan tool to check for codes and monitor the PCM.

Let me know and we can go from there. Thanks
Apr 3, 2020 at 10:50 AM