Brake Warning Light Issue

Recently, a few times the brake warning light came on in my 2005 Buick Century but only when turning slowly into or out of a parking space. It goes off when I shut off and restart the engine and stays off during normal driving. I had my rear brakes replaced last year and at the time my mechanic said the front brakes were still good. My ABS hasn’t been working for 3 years, but that malfunction never caused the main warning light to come on.
The fluid reservoir is full, with no visible leaks from the master cylinder or the calipers.
The brake pedal travel seems normal.
The car doesn’t pull to one side when driving or braking.
Does this problem warrant immediate attention?
What is it about turning sharply into a parking space that can cause the warning light to come on?
Could it be caused by a glitch in the system?
An old friend and fellow Buick owner once said I should use the parking brake because it’s part of the self-adjusting system.

One thing that’s happened to me a couple of times on older cars is that the float sensor in the master cylinder, which measures brake fluid level, gets stuck. The brake fluid drops when you step on the brake, but then when it comes back up, the sensor sticks in the lower position and fools the system into thinking the fluid is low.

The fix is to clean the rod that the float sensor rides on - it’s full of gunk.

Also, when’s the last time you had the brake fluid exchanged?

IMO the ABS warrants immediate attention if for no other reason than if you happen to get into a wreck and someone finds out that you knew the ABS wasn’t working, that could expose you to legal liability.

For the other thing, check that float sensor first, and change the fluid if it hasn’t been done in the last 3 years. Then see if it keeps happening.


EVERY brake warning light warrants immediate attention!

Going is optional, stopping is not.

@shadowfax has good suggestions, it may be nothing serious, but until it is checked out you don’t know.