2010 Subaru Forester Brake Light Stays on when Car is Cold

OK, so I have a 2010 Subee, 36K miles. Three events here, added in car monitoring from State Farm for Ins Discount, had a nail in back tire which I had repaired, it’s been pretty cold at night here in GA. When I start the car, both the cold engine and the brake light are lit. Cold engine normal, takes it a few minutes then it goes out. Brake light is staying on until the car drives a bit (maybe 10 minutes?). No odd brake noises, brakes feel fine, emergency brake fully released. Recently had fluids checked and oil changed at Jiffy Lube. Have had the car for 3 years, this is new. It didn’t do it last winter. So - do I need to go to the dealership? A brake place? Check the brake fluid. Cry and go lie down? Any suggestions would be helpful. thanks much.

" Recently had fluids checked and oil changed at Jiffy Lube."

As one of the veteran members of this board likes to say, “Don’t ever go to a fast lube place–not even for directions”.

Seriously–I wouldn’t trust the poorly trained kids at J-Lube to even know how to change oil without screwing things up. I certainly wouldn’t trust their judgment on the level of brake fluid in my master cylinder.

All of that being said, when your brake pads have worn to a certain extent, it is normal for the brake fluid level to drop–and to turn on the warning light.

If you are so inclined, you can check it yourself, and replenish it with DOT-3 brake fluid which can be bought at any auto parts store. If you are not inclined to do this yourself, ANY mechanic can check/correct your brake fluid for you, and this doesn’t necessitate a visit to the dealership.

However, I strongly suggest that you have your brake pads checked by a mechanic in order to see just how much life is left in them. Your brakes will work properly with very scant friction material left–until the day when they no longer function properly and you lose the ability to stop the vehicle. The drop in brake fluid level is your sign that you need to have the brake pads checked.

And, regarding my suggestion of having any mechanic check your brakes, please bear in mind that the kids at Jiffy Lube are NOT mechanics. They have been given minimal training in order to do some very basic servicing, and that is a far cry from being a mechanic.

By “brake light” I’m assuming you mean the dashboard brake light.

hmmm … I’m wondering all the things that are supposed to turn the dash brake light on. What are they?

It should come on when

  1. Engine is off, key in “on”.
  2. Engine is running, something wrong w/hydraulic brakes, like the fluid is low, or ABS problem.
  3. Engine is running, emergency brakes are on.
  4. On some cars there is an interaction between the alternator warning light and the brake warning light.

Here’s what I’d do

  • Determine if the rear brake lights (including the high mounted one) are working.
  • Make sure all the dash lights that are supposed to come on when the key is in “on” but the engine isn’t running are, especially the alternator warning light.
  • Check the brake fluid level in the plastic bottle to verify it is above the “low” mark.
  • Have the diagnostic codes read at a shop to see if there’s a code stored for an ABS problem. You may need to use a shop that has a Subaru specific scan tool for this. Only applies if your Subie has ABS.
  • Ask the shop to test the operation of the emergency brake switch. It could be sticking when cold.

+1 for VDCdriver. They don’t call them “Iffy Lube” for nothing.