Replacement of a rear parking brake actuator (electric motor-on-caliper EPB) on a 2024 Tesla Model Y Long Range AWD. The actuator is integrated into the rear caliper assembly and requires the EPB to be placed in service/maintenance mode via the touchscreen before removal.

Warnings

Tools required

Parts

• Rear parking brake actuator (motor-on-caliper) × 1 — Tesla Model Y rear EPB actuator — left or right specific; order via Tesla Parts or verified OEM equivalent
• Actuator-to-caliper seal/O-ring (if supplied separately) × 1 — Comes with actuator kit on most OEM units
• Actuator mounting bolts × 3 — Reuse only if undamaged; replace per OEM specification

Preparation

1. Park on level ground, place in P, engage parking brake.
2. Exit ALL doors with key fob away from the vehicle. Wait at least 2 minutes for HV systems to fully de-energize, even on this non-HV job.
3. Disconnect the 12V low-voltage battery (located under the rear seat / under access panel in front trunk area depending on build — refer to architecture notes).
4. DO NOT touch, cut, or pierce ANY orange cable — these are high-voltage and lethal.
5. If at any point you encounter an orange cable, an HV component, or are unsure if a system is de-energized: STOP and consult a Tesla-certified technician.
6. BEFORE disconnecting 12V: on the touchscreen, navigate to Service → Brakes → 'Brake Service Mode' (or equivalent EPB Maintenance Mode) and engage it. This retracts the EPB pistons to allow safe removal. Confirm both rear actuators have retracted.
7. Loosen rear wheel lug nuts while vehicle is on the ground.
8. Raise the vehicle using Tesla-approved jack pad locations only — never under the battery pack. Support on jack stands.
9. Remove the affected rear wheel.

Procedure

1. 1

   Confirm EPB is in service mode
   Verify on the touchscreen that the parking brake is in the released/service position. If 12V has already been disconnected and the EPB was not pre-released, you will need to reconnect 12V briefly and complete service mode entry before continuing — do not attempt mechanical override unless documented in the Tesla Service Manual.
   ⚠️An energized actuator can clamp without warning. Verify service mode is active before any disconnection.
2. 2

   Disconnect actuator electrical connector
   Locate the actuator connector at the rear of the caliper. Release the connector lock tab using a trim tool and unplug. Inspect pins for corrosion or water intrusion; clean if needed and apply a small amount of dielectric grease on reassembly. Tuck the harness aside and protect from contamination.
3. 3

   Inspect and clean actuator mounting area
   Wire brush around the perimeter where the actuator meets the caliper body to prevent debris from falling into the gear interface. Spray with brake cleaner and allow to dry.
4. 4

   Remove actuator mounting fasteners
   Remove the fasteners (typically three) securing the actuator to the rear caliper body. Support the actuator while removing the last fastener to prevent it from dropping. Pull the actuator straight off — do not pry against the caliper casting.
   ⚠If the actuator does not separate freely, do not strike it. Verify EPB is fully retracted and inspect for a hidden retaining feature per the service manual.
   Torque spec

   Mounting Bolts27 Nm (20 lb-ft)
5. 5

   Inspect caliper gear interface and seal
   Inspect the spindle/gear interface inside the caliper for damage, corrosion, or seized condition. The piston should rotate freely. If the caliper itself shows damage or the piston is seized, the caliper assembly must be replaced — actuator alone will not resolve the fault.
6. 6

   Install new actuator
   Align the new actuator's drive coupling with the caliper spindle. Seat the actuator flush against the caliper body without forcing — the gear teeth must mesh. Verify the seal/O-ring is properly positioned. Hand-thread all mounting fasteners before torquing.
   ⚠Forcing the actuator without proper gear alignment will damage the new unit.
7. 7

   Torque actuator fasteners
   Torque the actuator mounting bolts evenly in a cross pattern to the manufacturer-specified value. Torque to OEM specification — refer to Tesla Service Manual if specific value differs from generic mounting bolt spec.
   Torque spec

   Mounting Bolts27 Nm (20 lb-ft)
8. 8

   Reconnect electrical connector
   Reconnect the actuator harness, ensuring the lock tab fully engages with an audible click. Verify the connector is fully seated and weather seal is undamaged. Route harness back into its original retainers.
9. 9

   Reinstall wheel
   Mount the wheel and hand-thread all lug nuts. Snug in a star pattern, then lower the vehicle and final-torque on the ground.
   Torque spec

   Wheel Lug Nuts140 Nm (103 lb-ft)
10. 10

    Reconnect 12V battery and exit service mode
    Reconnect the 12V battery. Allow the vehicle to fully wake (touchscreen boots, gateway online). Navigate to Service → Brakes and exit Brake Service Mode. The system will perform an EPB calibration cycle — you will hear the actuators apply and release. Confirm no parking brake fault is displayed.
    ℹ️If a fault persists, a full EPB calibration via Tesla Toolbox may be required. Do not attempt to clear faults by disconnecting the 12V repeatedly.

Reassembly

1. Confirm wheel lug nuts are torqued to spec in a star pattern.
2. Verify all harness retainers are reseated and no wiring is pinched against the caliper or suspension.
3. Confirm rear wheel spins freely with EPB released and binds with EPB applied.
4. Clean any brake cleaner residue from the rotor face before driving.

Verification

• On the touchscreen, confirm no parking brake or ABS warning indicators are present.
• Apply and release the parking brake several times via the touchscreen and gear selector — actuator should cycle audibly and smoothly on both sides.
• Perform a low-speed roll test on a slight incline: place in N, confirm the EPB holds the vehicle when applied.
• Drive test at low speed and verify no dragging or unusual noise from the rear corner.
• After ~50 miles, recheck wheel lug torque (Tesla's published recommendation after wheel removal).
• Note: Tesla recommends brake fluid replacement every 2 years regardless of mileage — if the fluid is due, schedule that service separately.

More procedures for this vehicle