Rebuild the cylinders on that caliper.
You might be out of brake fluid. Our rear wheel cylinder was leaking and ran ours out of fluid and the light came on.
IF you have rear wheel drive it may be a grease seal for the rear differential. Otherwise it is probably a wheel cylinder. Check your brake fluid level. GEt this fixed ASAP- Safety concern. Wheel cylinder, brake fluid.. If it's a rear wheel drive vehicle, it may be the axle seal leaking as well. Hello... hello...
your wheel cylinder is leaking,you will need to buy a rebuilt or new whl cylinder also new brake shoes and a can of brake cleaner.
I found out it`s the cylinder
leaking wheel cylinder
it is usually the rear brake cylinder that's leaking and needs to be replace on that side.
There are 2 rubber seals on each end of the wheel cylinders and there leaking. REPLACE THE WHEEL CYLINDERS.
Failed caliper, wheel cylinder, hose, line, Vehicle is unsafe to drive.
Most likely brake fluid. Check the master cylinder level.
Obviously you have a leak. Can be leaking at a caliber or wheel cylinder, which you can see on the backside of the wheel/tire. Can be leaking at a fitting, or at the master cylinder itself. You are just going to have to get under there and start looking.
Check the wheel cylinders - they may be leaking and you can't see it on the outside of the wheel
That sounds like a wheel cylinder leaking brake fluid.