Skip the auto shop - Our mechanics make house calls

Q: Battery drain, brake warning light on

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Interior is falling apart, need help

Walk through any classic car show, glance at a car's interior, and usually the most prominent, gleaming feature of a 50’s vehicle will be the dashboard: beautifully painted metal, adorned with brushed aluminum or chrome, shining brightly. Sadly, while being...

Q: I was thinking about buying a 2000 land rover discovery and read a few reviews. Maintenance and gas mileage were the to biggies.

If it's reliability and low maintenance you want, you'd better look past the Land Rover. It's a shame, because they are really cool cars, but they are very expensive to maintain and are prone to failures. As much as I...

Q: On interstate, engine died, idled, no power

Hello there, The TPS can be a serious issue if the car dies like it did. I would not recommend driving the vehicle until repairs have been performed. There is no recall for this fault though there is a technical...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...