Product Specification

The BYD Song PLUS Rear Brake Disc is a core rear braking system accessory developed specifically for this vehicle model. Designed to OEM OE specifications, it fits Song PLUS DM-i and EV all series, covering 2021-2025 models.

This product is made from HT250 high-carbon gray cast iron, precision CNC-machined with anti-corrosion coating, offering excellent thermal stability and braking smoothness. It directly replaces worn or warped original brake discs.

BYD Song PLUS Rear Brake Disc Installation Guide

Safety Precautions

Electronic Parking Brake Must Enter Service Mode: The Song PLUS is equipped with an EPB electronic parking brake. Before replacing the rear brake disc, a diagnostic tool must be used to enter EPB Service Mode to fully retract the rear brake caliper motor. Never pry the caliper piston directly, as this will damage the internal spindle structure of the caliper.

Brake fluid is corrosive: Avoid contact with skin or vehicle paint during operation. If contact occurs, rinse immediately with water.

Braking system affects driving safety: If lacking professional repair experience, it is recommended to have the replacement performed by an authorized service center or professional technician.

Removal Steps

Step 1: Lift Vehicle and Remove Rear Wheel

Park the vehicle on flat, hard ground. Engage the electronic parking brake and shift to P. After jacking up the rear wheel, safety stands must be used to support the vehicle. Never work relying on the jack alone. Loosen and remove the rear wheel nuts in a diagonal sequence with a lug wrench, then remove the wheel.

Step 2: Enter EPB Service Mode

Connect the diagnostic tool, enter the brake system menu, and select EPB Service Mode (EPB Open) to fully retract the rear brake caliper motor. Confirm the motor retraction sound is heard before proceeding with removal.

Step 3: Remove Brake Caliper

Use a matching socket to remove the brake caliper mounting bolts (typically two). After removing the caliper, hang it on a nearby body component with wire or a hook, ensuring the brake hose remains in a natural relaxed state. Never let the caliper hang and pull on the hose, as this may cause hose rupture or connector loosening.

Step 4: Remove Caliper Bracket (If Needed)

Some models require removing the caliper bracket to remove the brake disc. Unscrew the caliper bracket mounting bolts and remove the bracket.

Step 5: Remove Old Brake Disc

The brake disc is typically secured to the wheel hub bearing by a small retaining screw. After removing this screw, grip the disc with both hands and pull it outward. If the disc is rust-seized to the bearing, spray rust penetrant on the seam first, wait briefly, then gently tap the disc edge with a rubber mallet while slowly rotating it to break the rust bond. Avoid striking the bearing area with force to prevent damaging the bearing seal.

Installation Steps

Step 6: Clean and Install New Brake Disc

Before installation, clean rust and debris from the wheel hub bearing surface to ensure a clean mating surface. Clean the anti-rust oil from the new brake disc surface with brake cleaner. Align the new disc with the hub bearing locating holes, push it gently into place, and tighten the retaining screw. Rotate the disc by hand to confirm no binding or runout.

Step 7: Reinstall Caliper Bracket and Caliper

Reinstall the caliper bracket and tighten the bolts to specification. Install the brake caliper back into position and tighten the mounting bolts. Note: Before installation, confirm the caliper piston is in the retracted position. If not fully retracted, verify EPB Service Mode is still active with the diagnostic tool.

Step 8: Exit EPB Service Mode

Use the diagnostic tool to exit EPB Service Mode (EPB Close / EPB Learning) to reset and relearn the caliper motor. Confirm the motor operation sound is heard.

Step 9: Install Wheel and Tighten

Reinstall the rear wheel, hand-thread all nuts, then tighten in a diagonal sequence with a torque wrench to specification (typically approximately 100-120 N·m; refer to the repair manual). Lower the vehicle.

Step 10: Brake System Test

Before starting the vehicle, press the brake pedal 5-10 times consecutively until the pedal travel returns to normal, allowing the brake pads to seat against the new disc. Start the vehicle and drive at low speed, testing braking with light pedal application. Confirm no abnormal noise, no judder, and no spongy pedal feel.

Important Notes

EPB caliper has special structure: The Song PLUS rear brake caliper has an internal spindle structure. Absolutely forbidden to compress the piston directly with a C-clamp or pry bar. A diagnostic tool must be used.

Brake pad replacement recommended: When replacing the brake disc, it is recommended to replace the brake pads at the same time to ensure proper friction surface matching.