Brake Caliper Servo Motor

A control element for a parking brake caliper, often referred to as a parking brake actuator or parking brake mechanism, is a vital component of a vehicle's parking brake system. This system ensures the vehicle remains stationary when parked, even on inclines, by mechanically locking the rear brakes.

OE Number

Components and Functionality
1.  Parking Brake Lever:
- Function: Initiates the parking brake mechanism.
- Description: The lever inside the vehicle that the driver pulls or pushes to engage the parking brake.  In some modern vehicles, this may be replaced by an electronic switch.
2.  Parking Brake Cable:
- Function: Transmits force from the lever to the caliper.
- Description: A steel cable that connects the parking brake lever to the parking brake caliper.  When the lever is engaged, it pulls the cable, which activates the parking brake mechanism.
3.  Actuation Mechanism (Actuator):
- Function: Converts the cable pull into mechanical force to engage the brake pads.
- Description: The actuator, located in or near the brake caliper, translates the force from the parking brake cable into a clamping force that presses the brake pads against the rotor.
4.  Return Spring:
- Function: Releases the brake pads when the parking brake is disengaged.
- Description: A spring that ensures the brake pads retract when the parking brake lever is released, preventing drag and wear on the brake pads and rotors.
5.  Adjustment Mechanism:
- Function: Maintains the correct tension in the parking brake cable.
- Description: A mechanism that adjusts the length of the parking brake cable to compensate for wear in the brake pads and ensure consistent braking performance.

Types of Parking Brake Calipers
1.  Mechanical Parking Brake Caliper:
- Usage: Common in older vehicles and some modern vehicles.
- Functionality: Uses a mechanical linkage to apply the brake pads against the rotor when the parking brake is engaged.
2.  Electric Parking Brake (EPB) Caliper:
- Usage: Common in newer vehicles.
- Functionality: Uses an electric motor to engage the parking brake.  The system is activated by a button or switch inside the vehicle, replacing the traditional hand lever or foot pedal.

Importance of the Parking Brake Control Element
1.  Safety:
- Ensures the vehicle remains stationary when parked, preventing accidental movement.
2.  Convenience:
- Simplifies the process of securing the vehicle, especially on inclines or uneven surfaces.
3.  Reliability:
- Reduces the reliance on the primary braking system when the vehicle is stationary, thereby reducing wear on the main brake components.

Maintenance and Issues
1.  Regular Inspection:
- Periodically check the condition of the parking brake cable and actuator for signs of wear, corrosion, or damage.
2.  Adjustment:
- Ensure the parking brake cable is properly adjusted to maintain optimal tension and braking performance.
3.  Lubrication:
- Apply appropriate lubricants to the moving parts of the parking brake mechanism to prevent rust and ensure smooth operation.
4.  Signs of a Faulty Parking Brake Control Element:
- The parking brake does not hold the vehicle securely.
- Excessive travel or resistance in the parking brake lever.
- Unusual noises when engaging or disengaging the parking brake.
- A dashboard warning light indicating an issue with the parking brake system.

Proper maintenance and timely replacement of the parking brake control element are essential for ensuring the parking brake system operates effectively and safely.