If your vehicle is showing brake warning light stays on after releasing parking brake, here are the most likely causes and the parts you'll need to fix each one.
As brake pads wear down, the caliper pistons extend further, drawing brake fluid out of the reservoir. When the fluid drops below the minimum line, it triggers the brake warning light.
A small mechanical switch under the parking brake lever or pedal detects when it is engaged. If this switch gets sticky, bent, or fails, it will keep the light on even when the brake is released.
Rust, dirt, or fraying can cause the parking brake cable to bind inside its housing. Even though you released the handle, the cable doesn't fully retract, keeping tension on the switch and the rear brakes.
A leak in the hydraulic system causes a rapid drop in brake fluid, triggering the warning light. This is often caused by a ruptured hose, rusted line, or a loose fitting after a recent brake job.
The float inside the brake fluid reservoir can become saturated and sink, or the electronic sensor itself can fail, falsely indicating that the fluid is low.