This procedure replaces the electronic parking brake motor on the rear brake caliper assembly. This is a safety-critical brake system component requiring proper electronic retraction and calibration.

Warnings

Tools required

Parts

• Electronic parking brake motor assembly × 1 — Use OEM specification
• Brake fluid (DOT 4 LV) × 1 — Motorcraft PM-20

Fluids

• Motorcraft DOT 4 LV Brake Fluid — 0.25 qt

Preparation

1. Verify you have an OBD-II scan tool capable of EPB service functions (retract/reset). Generic code readers will NOT work for this procedure.
2. Park vehicle on level concrete surface. Place transmission in Park. Turn off engine.
3. Place wheel chocks at front wheels.
4. Open hood and disconnect negative battery terminal. Wait 2 minutes for system capacitors to discharge.
5. Reconnect negative battery terminal (required for EPB retraction).
6. Turn ignition to ON position without starting engine.
7. Using scan tool, navigate to EPB service functions and select 'Retract EPB Motor' or 'Service Mode'. Follow scan tool prompts to fully retract both rear parking brake motors. You should hear motors running.
8. Verify retraction is complete via scan tool confirmation message.
9. Turn ignition OFF and disconnect negative battery terminal again.
10. Loosen wheel lug nuts on the rear wheel for the side being serviced while vehicle is on ground.
11. Raise rear of vehicle with floor jack at manufacturer-specified jacking point.
12. Support vehicle with jack stands at frame contact points. Ensure vehicle is stable.
13. Remove rear wheel completely.

Procedure

1. 1

   Access electronic parking brake motor
   Locate the electronic parking brake motor on the rear of the brake caliper. It is a cylindrical motor assembly with an electrical connector. Inspect the area and clean any dirt or debris with brake cleaner to prevent contamination during disassembly.
2. 2

   Disconnect electrical connector
   Press the locking tab on the EPB motor electrical connector and carefully pull the connector straight off the motor. Do not pull on wires. Inspect connector terminals for corrosion or damage. If connector is corroded, address before proceeding.
   ⚠Do not allow connector to contact brake fluid during service. Brake fluid will damage electrical components.
3. 3

   Remove parking brake cable (if applicable)
   Depending on model year and configuration, a backup mechanical cable may be present. If present, use needle nose pliers to compress the cable retaining clip and disconnect the cable from the caliper lever. Note the routing for reinstallation.
4. 4

   Remove EPB motor mounting bolts
   Locate the two mounting bolts securing the EPB motor to the rear of the caliper. Using the appropriate socket, remove both mounting bolts. Support the motor as you remove the second bolt to prevent it from falling.
   ⚠Motor may be seized due to corrosion. If bolts are extremely tight, apply penetrating oil and wait 15 minutes before attempting removal.
   Torque spec

   Mounting Bolts31 Nm (23 lb-ft)
5. 5

   Remove EPB motor assembly
   Carefully pull the EPB motor straight out from the caliper housing. The motor actuator shaft will disengage from the internal piston screw mechanism. Inspect the motor mounting surface and O-ring groove on the caliper for damage, corrosion, or debris. Clean thoroughly with brake cleaner.
   ℹ️Note the orientation of the motor before removal. The new motor must be installed in the same rotational position.
6. 6

   Inspect caliper piston mechanism
   With the motor removed, you can see the internal piston screw mechanism. Inspect for damage, excessive wear, or seized operation. The screw should rotate freely by hand. If the internal mechanism is damaged, the entire caliper requires replacement, not just the motor.
   ⚠Do not push brake piston inward at this time. Piston position must remain as-is for motor installation.
7. 7

   Prepare new EPB motor
   Remove new EPB motor from packaging. Verify it matches the old motor in connector type and mounting configuration. Check that a new O-ring or seal is included with the motor. If a seal is present on the old motor but not included with the new one, carefully remove and inspect the old seal for reuse (not recommended - obtain correct seal).
8. 8

   Install new EPB motor
   If a new O-ring/seal is included, install it in the groove on the caliper housing. Lightly lubricate the seal with clean brake fluid (do not use petroleum-based lubricants). Align the new motor actuator shaft with the internal caliper piston screw. The motor will only install in one rotational position. Push the motor firmly into the caliper housing until it seats completely against the mounting surface.
   ⚠Ensure motor is fully seated before installing bolts. Incomplete seating will cause bolt misalignment and motor damage.
9. 9

   Install mounting bolts
   Apply a small amount of medium-strength thread locker to the threads of both mounting bolts. Insert both bolts and hand-tighten. Using a torque wrench, tighten both mounting bolts to specification in a cross pattern (alternate between bolts).
   ℹ️Do not exceed torque specification. Over-tightening can crack the motor housing.
   Torque spec

   Mounting Bolts31 Nm (23 lb-ft)
10. 10

    Reconnect electrical connector
    Align the electrical connector with the motor terminals and push firmly until you hear/feel the locking tab click into place. Gently tug on the connector to verify it is locked. Ensure the wire has adequate slack and is not stretched or kinked.
11. 11

    Reconnect parking brake cable (if applicable)
    If a mechanical backup cable was disconnected, reconnect it to the caliper lever and install the retaining clip. Ensure the cable is properly seated and routed as originally configured.
12. 12

    Reinstall wheel
    Clean the wheel hub face and wheel mounting surface. Install the wheel and hand-tighten all lug nuts in a star pattern. Do not fully torque at this time.
13. 13

    Lower vehicle and torque wheels
    Raise vehicle slightly with floor jack to unload jack stands. Remove jack stands. Lower vehicle completely to the ground. Using a torque wrench, tighten wheel lug nuts to specification in a star pattern.
    Torque spec

    Wheel Lug Nuts140 Nm (103 lb-ft)
14. 14

    Calibrate EPB system
    Reconnect negative battery terminal. Turn ignition to ON position without starting engine. Using the scan tool, navigate to EPB service functions and select 'EPB Calibration' or 'Learn Procedure'. Follow all scan tool prompts. The motors will run through several extend/retract cycles. This process typically takes 2-3 minutes. Wait for completion message before proceeding.
    ⚠️Do not interrupt the calibration process. Loss of power during calibration can result in EPB system malfunction.
15. 15

    Clear fault codes
    Use the scan tool to check for any EPB-related fault codes. Clear any codes related to the repair. If codes immediately return, do not drive the vehicle - diagnose the issue before operation.

Reassembly

1. If both rear EPB motors are being replaced, repeat entire procedure for opposite side before calibration.
2. Ensure all tools and equipment are removed from under vehicle.
3. Store all wheel chocks and jack stands properly.
4. Dispose of old EPB motor according to local electronic waste regulations.

Verification

• With engine running and vehicle in Park on level ground, activate the electronic parking brake using the dashboard switch. Verify you hear/feel the motor operate and the EPB warning light illuminates on the dashboard.
• Release the EPB using the switch (brake pedal must be depressed). Verify the motor operates and the warning light extinguishes.
• Perform parking brake holding test: On a slight incline (if safe), activate EPB and shift to Neutral. Vehicle should remain stationary. Do NOT exit vehicle during this test.
• Test drive vehicle in a safe area at low speed (under 10 mph). Verify normal brake operation and that EPB warning light does not illuminate during driving.
• Perform a low-speed EPB application test (dynamic test): While driving slowly in a safe area (5-10 mph), pull and hold the EPB switch. Vehicle should decelerate smoothly. This verifies motor is operating correctly.
• Check for any brake fluid leaks around caliper and EPB motor area after test drive.
• Use scan tool to verify no EPB fault codes are present after testing.
• If any warning lights remain illuminated or unusual noises occur, do not operate vehicle - seek professional diagnosis immediately.

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