Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Intermittent Battery Light Ford Explorer

I’ve got a 2007 Ford Explorer. About a week ago I noticed that the red battery icon showed up. I hit the reset button for diagnostics/system check and got the “Check Charging System” message. OK, fine. Several minutes later I hit the button again - this time it said “Charging System OK”. It’s been going on/off now for the last week or so. What seems to bring it on is this: if I’m at a stop light and my air conditioner is on full blast, I get the battery light. If I turn off the AC at a stop light, the light doesn’t come on. Even if the light does come on, once I get away from the stop light, everything seems to be OK.

I figure that whatever is going on is going to get worse and I’ve been lucky I haven’t been stranded so far. Any thoughts as to what it might be? Should I try to tackle this myself or just take it to the mechanic? Thanks

If you are in the US your local Auto Zone will check the battery and alternator for free.
As for doing it yourself since your skill level is unknown can’t answer that.


If OP knows how to work a DVM, the first test I’d do in that situation is to measure voltages at the battery terminals. Before first start of the day, battery should measure about 12.6 volts. Immediately after starting the engine, 13.5 -15.5 volts. Let us know what you measure.

Have someone inspect the serpentine belt for wear.