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Parking Brake/Check Battery Light always on

I have a 2003 Hyundai Elantra with 94,000 miles. I recently noticed that the parking brake light and check battery light remain on while I’m driving, when the parking brake is definitely not on. Also, just replaced the battery last month. Is this a symptom of a larger electrical problem?


That combination of warning lights is almost always an indication of a failing alternator.
In fact, it is entirely possible that your old battery’s life was shortened by a failing alternator.
Before you wind up needing a tow and needing to replace that month-old battery, I urge you to have the alternator’s output checked–tomorrow morning.

I think that there is likely a 98% probability that you need to replace the alternator.

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Concur w @VDCdriver … bad alternator is the prime suspect. OP might justifiably wonder why the brake warning light would come on if the alternator is the problem. It’s a fail safe mechanism. If the warning bulb for the alternator light burns out, the brake light will at least indicate to the driver there’s a problem needing immediate att’n. OP needs to take the vehicle to the shop immediately, b/c if the alternator is actually going out the battery will discharge enough the engine won’t run and the OP will suddenly find themselves stalled on the side of the road.

Might also want to check the brake fluid level

There was an equipment operator in our fleet, said the red brake warning light was always on

He thought it was some kind of electrical problem

The parking brake was not activated

Turns out the light was on, due to low brake fluid level, due to a leak

Even though in OP’s case, the red brake warning light may be on because of a charging system problem, might want to make sure it’s not coming on for a legitimate brake-related reason


Agree. That little light that says battery actually means charging system which means alternator, not battery. I don’t know what they would print it that way but maybe because more people would know what a battery is than an alternator.

It might not appear your parking brake is applied, but if that light is illuminated, you need to make sure that isn’t the case by checking more than the parking brake lever/pedal. The parking brake cable or the brake shoes might be bound up.

How did you confirm the parking brake isn’t applied, even just a little?

Also, most auto parts stores will test your battery for free. Some will even test your whole charging system for free.

That’s a darn good point! I forgot that the brake light can come on due to low brake fluid.

Yeah agree with db, if its just the brake light and not the specific parking brake light, it goes on when the fluid level is low (usually due to worn brake pads).

Thanks everyone. Just took the car in and sure enough the alternator was worn out.

You’re welcome!
I just hate it when I’m right…