Parking brake (Hand brake) light stays on

The parking brake, also sometimes referred to as the hand brake is designed to hold your car stationary when you park. The Parking Brake light should turn on when you engage the brake, and turn off when the brake is disengaged. However, if the Parking Brake light stays on, there may be one of several problems with the system.

How this system works:

Your parking brake system is a supplemental safety system designed to help secure your car when parking on an incline. However, the Parking Brake light is actually a multifunctional indicator. It turns on when you pull the parking brake handle to warn you that the brake is engaged when starting the car.

When you pull the handle, a cable engages the brake, which is located in the rear of the vehicle. There is also a switch that is responsible for sensing the brake being engaged, and then turning on the light in your dash. However, it is also designed to illuminate in several other situations, several of which have little to no connection with the parking brake itself.

Common reasons for this to happen:

  • Faulty Switch: One common reason for the Parking Brake light to stay on is a failing or failed switch. This can be checked easily by moving the handle to and fro after it is down. If the light turns off (or turns off and then back on), the switch is the most likely culprit and will need to be replaced.
  • Brake Handle Not Completely Lowered: Another reason for the light to stay on is if the brake handle is not completely lowered. Double-check that the handle is all the way down and that the parking brake is disengaged. Any pressure on the parking brake cable will cause the light to stay on.
  • Parking Brake Not Disengaging: Sometimes the trouble isn’t with the switch or the cables, but with the parking brake itself. If the brake does not disengage when the handle is lowered, the warning light will stay on in the dash.
  • Low Brake Fluid: Your Parking Brake light is a multifunction device, and is designed to illuminate if the fluid level in the reservoir drops below a certain point. You may notice the light turning on or off when going around turns as the fluid level changes.
  • Bad Level Sensor: Your master cylinder is equipped with a brake fluid level sensor. It’s sometimes mounted in the side of the sensor, and is sometimes part of the reservoir cap. If the sensor fails or is going bad, the Parking Brake light will turn on.
  • Uneven Fluid Pressure: If your car is experiencing uneven brake fluid pressure in one or more lines, it will affect braking performance, and could possibly cause the vehicle to pull to one side or the other during braking. It can also turn on the Parking Brake light in your dash.

How important is this service?

While your parking brake is not integral to safe driving, it’s an important component on your car. Moreover, a Parking Brake light that will not go out can indicate many different things, including the parking brake not disengaging, a failed parking brake switch, or even low fluid in the master cylinder reservoir. It is important for your safety to have the issue diagnosed and promptly fixed.