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Q: Battery drain, brake warning light on

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The battery in my car keeps getting drained. I had the battery tested and it checks out fine. Also, it is relatively new, about ten months old. Also, the dashboard shows the brake warnning light illuminated occasionally. When the light comes on, my battery power drops to low. What should I do?

Hello. If the battery is draining as the vehicle sits then most of the time this is caused by a failing ignition switch. I have had a lot of these fail on this vehicle.

I usually start by doing a voltage drop test of the switch to see if it is failing. If it is fine then the issue may be a sticking relay or a module problem. At that point I would perform a parasitic draw test on the battery and isolate each circuit while I try to find the one that is not turning off as it should.

If you need to have this looked at, consider YourMechanic, as a certified mechanic can come to you home or office to diagnose you draining battery and repair this.

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