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Q: Mercury Mariner battery light

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Hey, Peter. I own a 2009 Mercury Mariner. Upon start up, the battery light came on 30 seconds later. It was intermittent 3 days ago. Now it's steady. I took it to Autozone and the battery charge was at 74%. I had replaced the battery 4 weeks ago after a few hard cold weather starts. I had heard it may be the voltage regulator part of the alternator. Can recharging the battery be a short term fix? I've been making daily trips of about 10 miles and back for a training class with no radio, heater blower or other equipment. The headlights do pulse some, but still starts up ok. I'm in Cincinnati. Can I make it home to Columbus with a recharged battery and get the proper fix at a sooner than later time, of course. It's about 140 miles away. Thanks for the assistance.

My car has 124000 miles.
My car has an automatic transmission.

One hundred forty miles is too far if your alternator has failed, even if you depart with a fully charged battery. In your circumstance, what you want to determine is charging output at the battery posts. Charging output should be around 14.5 volts but the exact value will be stated in your Factory Service Manual. Of course, be sure the problem is not just simply bad terminal connections at the battery thus preventing the charging circuit from being completed. Your battery should also be load tested. If you want these steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an alternator inspection/diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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