Replace the electronic parking brake (EPB) motor/actuator on a 2024 Model 3 Long Range. The EPB motors are integrated into each rear caliper; this procedure covers removing the failed actuator from the rear caliper body and installing a new one without opening the hydraulic circuit.

Warnings

Tools required

Parts

• Rear EPB caliper actuator motor × 1 — OEM Tesla Model 3 rear EPB motor assembly — order by VIN
• Actuator-to-caliper O-ring/seal (if supplied separately) × 1 — Included with new actuator on most OEM kits

Preparation

1. Park on level ground, place in P, and engage the parking brake (you will release it electronically in a later step before removal).
2. Exit ALL doors with the key fob/phone key 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. On 2024 Model 3, the low-voltage battery is accessible behind the right rear seat back panel (some 2024 builds use a lithium 12V under the floor — confirm by VIN before disturbing trim).
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 the 12V: enter the vehicle's service screen and place the EPB into 'Service Mode' / 'Caliper Service' to retract the EPB pistons. This MUST be done with 12V power live. Only after the EPB is in service mode should the 12V be disconnected.
7. Loosen the rear lug nuts while the wheels are on the ground.
8. Lift the rear of the vehicle at the Tesla-specified rear jack points, support on jack stands, and remove the rear wheel(s) on the affected side(s).

Procedure

1. 1

   Confirm failure mode before replacing
   Before installing a new actuator, confirm the failure: read EPB fault codes via the touchscreen service menu or a compatible scan tool. Common failure modes are (a) actuator motor open/short circuit, (b) seized gear train, (c) connector corrosion. If the only fault is 'EPB switch' or 'parking brake not applied,' inspect the connector at the actuator and the EPB switch on the center console BEFORE buying a motor.
2. 2

   Place EPB in service/retract mode
   With 12V still connected and the vehicle awake, navigate to Service > Brakes (or use a compatible EPB scan tool) and command 'Service Mode' / 'Caliper Service Position.' Listen at the rear caliper — you should hear the actuator motor wind back. If the motor does not respond on the failed side, you will need to manually wind the actuator back during removal (covered later). Once retracted, power down the vehicle and disconnect the 12V battery as outlined in preparation.
   ⚠Skipping this step is the #1 cause of broken EPB motors and damaged caliper pistons during DIY replacement.
3. 3

   Raise vehicle and remove rear wheel
   With the vehicle safely on stands, remove the rear wheel on the affected side. Inspect the rear caliper assembly: the EPB motor is the cylindrical actuator bolted to the rear (inboard) face of the caliper body, with a small electrical connector exiting it.
   Torque spec

   Wheel Lug Nuts140 Nm (103 lb-ft)
4. 4

   Disconnect EPB actuator electrical connector
   Locate the EPB motor's wiring pigtail. Release the harness retainer clip on the trailing arm/caliper bracket, then depress the connector lock tab and unplug the actuator. Inspect the connector pins for corrosion, green oxidation, or bent pins — corroded connectors mimic motor failure and the new motor will fail again if water is still entering the connector.
5. 5

   Remove the EPB actuator from the caliper body
   The actuator is retained to the caliper by two fasteners (typically Torx) threaded into the caliper rear face. Support the actuator with one hand while removing both fasteners evenly. Pull the actuator straight off its mounting boss — it will disengage from the internal pinion gear that drives the caliper screw mechanism. Do NOT pry against the caliper casting with a metal tool.
   ⚠If the actuator will not pull free, the internal screw is still loaded. Do not force it. Reconnect 12V and re-attempt service mode, or rotate the actuator's input gear by hand (carefully) to relieve load before removal.
   Torque spec

   Mounting Bolts27 Nm (20 lb-ft)
6. 6

   Inspect the caliper interface
   With the actuator off, inspect the caliper's actuator boss: the splined input shaft must rotate freely with light finger pressure on the pinion. If the input is seized, the failure is inside the caliper (spindle/screw assembly), not the motor — in that case the entire rear caliper must be replaced. Clean the mounting face of debris and old sealant with brake cleaner; do not allow cleaner to enter the splined bore.
7. 7

   Verify new actuator orientation
   Compare the new actuator to the old one: the gear/spline orientation, connector clocking, and any indexing tab must match. Many EPB actuators are 'home-positioned' from the factory and must NOT be hand-rotated before installation, or they will not engage the caliper screw correctly. Read the included instruction sheet from the OEM actuator before proceeding.
   ⚠Rotating a new actuator's input shaft before installation can move it out of its zero/home position and prevent reassembly.
8. 8

   Install the new EPB actuator
   Fit the new O-ring/seal (supplied with the actuator) onto the mounting boss. Align the actuator splines to the caliper input and seat the actuator flush against the caliper face — it should drop into place with no gap. If it stands proud, the splines are not aligned; remove and re-clock by a tooth. Install the two mounting fasteners hand-tight first to ensure the actuator pulls down evenly, then torque.
   ⚠Do not use the mounting bolts to draw a misaligned actuator down — you will shear the plastic housing or strip the caliper threads.
   Torque spec

   Mounting Bolts27 Nm (20 lb-ft)
9. 9

   Reconnect electrical connector
   Apply a light film of dielectric grease to the connector pins (optional but recommended given the rear-of-vehicle exposure). Plug the connector in until it audibly clicks, and re-secure the harness to its retainer on the trailing arm/caliper bracket so it cannot contact the rotor or suspension components.
10. 10

    Reinstall wheel
    Reinstall the rear wheel. Snug the lug nuts in a star pattern, lower the vehicle until the tire just contacts the ground, then final-torque in a star pattern.
    Torque spec

    Wheel Lug Nuts140 Nm (103 lb-ft)
11. 11

    Reconnect 12V and exit service mode
    Reconnect the 12V low-voltage battery and reinstall any trim removed for access. Wake the vehicle, then in the service menu command the EPB to exit 'Service Mode' / 'Caliper Service Position.' The actuator will run forward to apply the parking brake, then back off to its rest position. Listen for a smooth, single-tone motor cycle on both rear corners.
12. 12

    Clear fault codes and calibrate
    Clear any stored EPB DTCs via the service menu. Cycle the EPB switch on the center console several times (Apply / Release) and confirm the actuator responds promptly with no warning lamp or 'Parking Brake Fault' alert on the touchscreen.

Reassembly

1. Confirm both rear wheel lug nuts are torqued in a star pattern.
2. Confirm the EPB harness is routed away from the rotor and secured in its original retainer.
3. Confirm any rear seat trim or under-floor cover disturbed for 12V access is fully reseated and the seat back is latched.
4. Reset the touchscreen clock and any trip data lost from the 12V disconnect.

Verification

• On the touchscreen, verify no 'Parking Brake' or 'Service Brake System' alerts are present.
• With the vehicle in P on a slight incline, confirm the EPB holds the vehicle when the brake pedal is released.
• Apply and release the EPB manually via the center console switch at least 3 times — both rear actuators should cycle audibly and symmetrically.
• Drive the vehicle at low speed (under 10 mph) and trigger an emergency EPB apply via the console switch — the vehicle should decelerate cleanly with no pulling to one side.
• Re-scan for stored DTCs after a short drive cycle; any reappearing EPB fault indicates a connector or in-caliper mechanical issue, not a motor issue.
• Reminder: Tesla recommends brake fluid replacement every 2 years regardless of mileage — log the date and verify reservoir level while you have the wheel off.

More procedures for this vehicle