Replacement of the electronic parking brake (EPB) motor/actuator on a 2024 Model S Long Range AWD. The EPB motors are integrated into the rear caliper assemblies; this procedure covers retracting the EPB, removing the failed actuator, and installing a new unit on one rear corner.

Warnings

Tools required

Parts

• Electronic Parking Brake Motor/Actuator (rear, manufacturer-specified for 2024 Model S) × 1 — Tesla OEM EPB actuator — verify by VIN
• EPB actuator-to-caliper seal/O-ring (if supplied separately) × 1 — OEM seal kit if not included with actuator

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 in the front trunk (frunk) under the nose cowl panel. Follow Tesla's documented frunk-access procedure if the frunk will not open after power-down.
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: connect an OEM-level diagnostic tool and place the EPB into service/maintenance (open) mode so the actuator is fully retracted and unloaded.
7. Loosen rear wheel lug nuts while the vehicle is on the ground.
8. Raise the rear of the vehicle using Tesla-approved jack pads at the factory lift points and support on rated jack stands.
9. Remove the affected rear wheel.
10. Inspect the rear caliper, EPB actuator, and wiring harness; photograph routing and connector orientation before disassembly.

Procedure

1. 1

   Confirm EPB is in service mode
   Verify with the diagnostic tool that the EPB has been commanded to the service/open position and shows no residual clamping load. If service mode cannot be entered due to a failed motor, consult the service manual for the manual-release procedure specific to this caliper before proceeding.
   ⚠️Do not attempt to remove the actuator if it is still under spring or piston load — internal components can eject.
2. 2

   Disconnect EPB actuator harness
   Locate the EPB motor connector at the rear caliper. Release the connector lock and disconnect the harness. Free the harness from any retention clips on the caliper bracket and trailing arm so it can be moved aside without strain.
3. 3

   Inspect caliper and surrounding hardware
   Inspect the caliper body, slide pins, dust boots, and the EPB actuator mounting flange. Note the orientation of the actuator and any alignment features. Clean the actuator-to-caliper interface with brake cleaner and a lint-free rag to keep debris out of the caliper bore during removal.
4. 4

   Remove the EPB actuator from the caliper
   Remove the actuator-to-caliper fasteners (typically Torx or E-Torx) evenly. Support the actuator as the last fastener is removed. Withdraw the actuator straight off the caliper to avoid damaging the drive shaft/spindle that engages the piston adjuster. Cap or cover the caliper opening immediately to prevent contamination.
   ⚠If fluid weeps from the caliper or the piston moves during removal, STOP — the actuator should not be hydraulically connected. Reassess and consult the service manual.
5. 5

   Compare old and new actuators
   Place the new actuator next to the old one and verify identical mounting pattern, connector keying, drive interface, and seal location. Confirm the replacement is the correct side (left/right) and is the manufacturer-specified part for this VIN.
6. 6

   Install the new EPB actuator
   Fit a new seal/O-ring if supplied. Align the new actuator's drive feature with the caliper piston adjuster and seat the actuator flush against the caliper without forcing it. Start all mounting fasteners by hand to avoid cross-threading. Tighten the mounting fasteners evenly in a cross pattern.
   ⚠Torque to OEM specification — refer to Tesla Service Manual if the EPB actuator fasteners are listed separately from the generic mounting-bolt spec.
   Torque spec

   Mounting Bolts27 Nm (20 lb-ft)
7. 7

   Reconnect EPB harness
   Reconnect the actuator electrical connector until the lock fully seats (audible click). Reseat the harness in all original retention clips, ensuring there is no contact with the rotor, suspension links, or hot brake surfaces.
8. 8

   Reinstall the wheel
   Mount the rear wheel and start all lug nuts by hand. Snug them in a star pattern, then lower the vehicle so the tire just contacts the ground before final torque.
   Torque spec

   Wheel Lug Nuts140 Nm (103 lb-ft)
9. 9

   Final wheel torque
   With the wheel on the ground, torque the lug nuts in a star pattern to spec. Re-check torque after a short test drive.
   Torque spec

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

    Reconnect 12V battery and wake the vehicle
    Reconnect the 12V battery in the frunk. Close the frunk. Open a door to wake the vehicle and allow all modules to initialize. Expect transient warnings on the touchscreen during boot.
11. 11

    Calibrate / commission the new EPB actuator
    Using the OEM-level diagnostic tool, exit EPB service mode and run the EPB calibration / actuator initialization routine. Confirm both rear actuators clamp and release symmetrically. Clear any stored DTCs and verify no active brake-system faults remain.
    ⚠️Do not drive the vehicle until calibration completes successfully and the EPB applies and releases on command. An uncalibrated EPB may fail to hold the vehicle on a grade.

Reassembly

1. Confirm harness routing is clear of rotating and hot components.
2. Confirm all fasteners are torqued to spec and any threadlocker/grease has been applied per the service manual.
3. Confirm the wheel lug nuts are torqued in a star pattern with the vehicle on the ground.
4. Reset trip data only after the vehicle has been verified fault-free.

Verification

• On the touchscreen, confirm there are no active brake, ABS, ESC, or EPB warnings.
• With the vehicle stationary on a flat surface, apply and release the EPB several times via the touchscreen control; listen for symmetrical actuation at both rear corners.
• Perform a low-speed roll test (parking lot) and confirm no rear-brake drag, no pulling, and normal regenerative + friction braking behavior.
• Park on a moderate grade, shift to P, and confirm the EPB holds the vehicle without creep.
• Re-check rear wheel lug nut torque after approximately 80 km (50 mi).
• While servicing the brake system, note: Tesla recommends brake fluid replacement every 2 years regardless of mileage — verify service history and schedule fluid service if due.
• If rear pads/rotors were disturbed or showed wear, consider rear drive unit gear oil and tire rotation intervals (Tesla now recommends gear oil service rather than 'lifetime' fill, and tire rotation every ~6,250 mi).

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