Opening and closing the rear electronic parking brake (EPB) for brake maintenance requires specific procedures using VCDS Lite. This guide provides detailed instructions for retracting and resetting the rear brakes on vehicles equipped with EPB. Incorrect procedures can lead to system faults and potential safety hazards.
Opening the Rear Parking Brake with VCDS Lite
Before initiating the process, ensure all rear brake components, including pads and calipers, are fully assembled and properly installed on the rotors. Connect a battery charger according to your vehicle’s repair manual to maintain a stable voltage. Begin by cycling the parking brake ON and then OFF using the vehicle’s switch. This initial step prepares the system for the subsequent procedure.
Using VCDS Lite:
- Access Module 53: Connect VCDS Lite to your vehicle’s diagnostic port and select module 53 – Parking Brake.
- Enter Basic Settings: Navigate to Basic Settings – 04.
- Select “Start lining change mode”: Choose this option to initiate the opening procedure.
- Activate Basic Setting: Click [Go!] to activate the selected setting. This command signals the EPB to retract, allowing sufficient clearance for brake pad replacement. The calipers will open.
- Confirmation: Wait for the “Finished Correctly” message to appear on the VCDS Lite screen.
- Exit Basic Settings: Once the process completes, click [Stop], then [Done, Go Back], and finally [Close Controller, Go Back – 06].
Important Notes:
- Manual Piston Retraction: After completing the VCDS Lite procedure, the caliper pistons will remain extended. Use a suitable hand tool to push the pistons back into the calipers. This is necessary for proper pad and rotor installation.
- Warning Light: The parking brake warning light will likely flash during this service mode, indicating the parking brake is disabled. This is normal. Do not operate the EPB switch until the rear brakes are fully reassembled.
- Power Supply: Keep the battery charger connected throughout the entire procedure, including during rear brake reassembly.
Closing the Rear Parking Brake with VCDS Lite
After completing the brake service and ensuring all components are correctly reassembled, follow these steps to close the rear parking brake using VCDS Lite:
Prerequisites: All rear brake components must be reassembled, and a battery charger should be connected as per the repair manual.
Using VCDS Lite:
- Access Module 53: Connect VCDS Lite and select module 53 – Parking Brake.
- Enter Basic Settings: Navigate to Basic Settings – 04.
- Select “End lining change mode”: Choose this option to initiate the closing procedure.
- Activate Basic Setting: Click [Go!] to begin the process. The brake calipers will close, resetting the EPB to its normal operating position.
- Confirmation: Wait for the “Not Running” or “Finished Correctly” message to display.
- Exit Basic Settings: Click [Stop], [Done, Go Back], and [Close Controller, Go Back – 06] to exit the Basic Settings mode.
Final Steps:
- Cycle Parking Brake: With the engine running and the brake pedal depressed, cycle the parking brake ON and then OFF using the vehicle’s switch. This ensures proper system function.
- Fault Code Check: Before test driving, perform a fault code scan using VCDS Lite to ensure no errors are present. Address any fault codes before operating the vehicle.
Following these instructions precisely will ensure safe and effective rear brake retraction and reset using VCDS Lite. Always consult your vehicle’s repair manual for specific torque specifications and safety procedures.
