This procedure covers the removal and replacement of the ABS module (hydraulic control unit) on a 2011-2014 Ford F-150 with 5.0L V8, including brake line disconnection, module replacement, and system bleeding.

Warnings

Tools required

Parts

• ABS module (Hydraulic Control Unit) × 1 — Use OEM specification - Motorcraft AB-3289 or equivalent
• Brake fluid × 1 — Motorcraft DOT 4 LV
• Brake line copper washers/seals × 6 — Use OEM specification

Fluids

• Motorcraft DOT 4 LV Brake Fluid — 1.5 qt

Preparation

1. Park vehicle on level ground and place wheel chocks behind rear wheels
2. Ensure ignition is OFF and key is removed from vehicle
3. Disconnect negative battery terminal and wait 2 minutes for airbag system to discharge
4. Locate ABS module mounted to left frame rail near driver side front wheel well
5. Remove driver side front wheel using 21mm socket for access if needed
6. Place drain pan under ABS module location to catch brake fluid
7. Use turkey baster or fluid evacuator to remove as much brake fluid as possible from master cylinder reservoir to minimize spillage
8. Have at least 2 quarts of fresh Motorcraft DOT 4 LV brake fluid available
9. Clean area around ABS module and brake line fittings with brake cleaner to prevent contamination

Procedure

1. 1

   Access ABS module
   The ABS module is located on the driver side frame rail. Remove any splash shields or underbody panels blocking access. On some models, you may need to remove the inner fender liner partially. Use compressed air to clean dirt and debris from around the module and brake line connections.
2. 2

   Disconnect ABS module electrical connector
   Locate the large electrical connector on the ABS module. Press the locking tab and carefully disconnect the connector. Inspect connector pins for corrosion or damage. Do not allow connector to hang unsupported - secure it to prevent damage.
   ⚠The connector contains many small pins that are easily damaged. Do not force or pry.
3. 3

   Label and disconnect brake lines
   Using a permanent marker or tape, label all six brake lines at the ABS module with their position (e.g., LF-in, LF-out, RF-in, RF-out, rear-in, rear-out). This is critical for correct reassembly. Using ONLY a flare nut wrench (not a standard wrench), carefully loosen each brake line fitting one turn. Expect brake fluid to leak - have drain pan positioned. Once all fittings are loosened, completely remove each brake line from the module. Immediately plug open brake line ends with rubber caps or tape to prevent contamination.
   ⚠️Use only flare nut wrenches on brake line fittings. Standard wrenches will round off the soft brass fittings, requiring brake line replacement.
   ⚠Brake fluid will drain from lines. Keep drain pan in position and wipe spills immediately to prevent paint damage.
4. 4

   Remove ABS module mounting bolts
   Locate the mounting bolts securing the ABS module to the bracket (typically 3-4 bolts). Remove these bolts using the appropriate socket. Support the module as you remove the final bolt - it is heavy and will drop if not supported. Carefully lower the ABS module and remove it from the vehicle.
   ⚠The ABS module weighs approximately 8-10 lbs and contains residual brake fluid. Support it carefully to prevent dropping.
   Torque spec

   ABS Module Bolts10 Nm (7 lb-ft)
5. 5

   Inspect and clean mounting area
   Inspect the mounting bracket for corrosion, cracks, or damage. Wire brush any rust from the mounting surface. Check brake line fittings for damage or excessive corrosion. Clean the mounting surface thoroughly to ensure proper contact with new module.
6. 6

   Install new ABS module
   Position the new ABS module onto the mounting bracket, aligning all mounting holes. Install ABS module mounting bolts finger-tight initially. Torque bolts in a cross-pattern to specification using a torque wrench.
   ⚠Do not over-torque ABS module bolts. The housing is aluminum and threads can strip easily.
   Torque spec

   ABS Module Bolts10 Nm (7 lb-ft)
7. 7

   Install new brake line seals and connect brake lines
   Install new copper washers/seals on each brake line fitting. Reference your labels from step 3 to connect each brake line to the correct port on the ABS module. Thread each fitting by hand first to ensure proper threading. Once all fittings are hand-tight, use a flare nut wrench to tighten each fitting to specification. Tighten in a cross-pattern to ensure even seating.
   ⚠️Incorrect brake line routing will cause brake failure. Verify each line matches your labels before tightening.
   ⚠Do not cross-thread fittings. If resistance is felt when threading by hand, remove and inspect threads.
   Torque spec

   Brake Line Fittings15 Nm (11 lb-ft)
8. 8

   Reconnect electrical connector
   Clean the electrical connector with electrical contact cleaner if needed. Align and firmly press the electrical connector onto the ABS module until the locking tab clicks into place. Verify the connection is secure by gently tugging on the connector.
9. 9

   Fill master cylinder reservoir
   Fill the brake master cylinder reservoir with fresh Motorcraft DOT 4 LV brake fluid to the MAX line. Keep the reservoir filled throughout the bleeding process - check frequently to prevent air entry.
   ⚠️Never allow master cylinder reservoir to run empty during bleeding. This will introduce air into the ABS module requiring dealer-level scan tool bleeding.
10. 10

    Bleed brake system - manual method
    Bleed brakes in this order: RR (right rear), LR (left rear), RF (right front), LF (left front). For each wheel: attach clear tubing to bleeder screw, submerge other end in container with brake fluid, have assistant pump brake pedal 3-5 times and hold, open bleeder screw until fluid stops flowing, close bleeder screw before pedal reaches floor, repeat until no air bubbles appear. Torque bleeder screws to specification after bleeding each wheel. Check reservoir level after each wheel.
    ⚠️Do not allow pedal to go to floor with bleeder open. This can damage master cylinder seals.
    ⚠Check master cylinder reservoir after EACH wheel. Running dry will require restarting the entire procedure.
    Torque spec

    Bleeder Screw17 Nm (13 lb-ft)
11. 11

    Perform ABS module bleeding (scan tool method)
    If available, connect an OBD-II scan tool with ABS bleeding capability (Ford IDS or equivalent aftermarket tool). Follow scan tool prompts to cycle ABS solenoids and purge air from the module. This typically involves activating solenoids while bleeding at each wheel. If scan tool is not available, perform 20-30 hard stops from 40 mph in a safe area to self-bleed the ABS module, then re-bleed all wheels manually.
    ℹ️Without a scan tool, complete air removal from ABS module may take multiple bleeding cycles and test stops.
12. 12

    Verify brake pedal feel
    With engine running, pump brake pedal several times. Pedal should feel firm with 1-2 inches of travel before resistance. If pedal feels spongy or goes to floor, air remains in system - repeat bleeding procedure. Check all brake line connections for leaks while assistant applies firm pedal pressure.
    ⚠️Do not drive vehicle if brake pedal feels soft or travels to floor. This indicates air in system or a leak.
13. 13

    Reinstall wheel and lower vehicle
    If wheel was removed, reinstall it and torque lug nuts in star pattern to specification. Lower vehicle to ground. Torque lug nuts again after vehicle weight is on wheels.
    Torque spec

    Wheel Lug Nuts204 Nm (150 lb-ft)
14. 14

    Reconnect battery and initialize ABS system
    Reconnect negative battery terminal. Turn ignition to ON position (engine off). The ABS warning light should illuminate briefly then extinguish. If ABS light remains on, use scan tool to check for fault codes. Some vehicles may require dealer initialization of new ABS module.
    ⚠If ABS light remains illuminated, the module may require programming or a fault exists. Do not ignore warning lights.

Reassembly

1. Reinstall any splash shields or inner fender liner components removed for access
2. Top off brake fluid reservoir to MAX line with fresh DOT 4 LV fluid
3. Double-check all brake line fittings are tight and properly torqued
4. Verify all electrical connections are secure and locked
5. Clean any spilled brake fluid from frame, suspension, and painted surfaces

Verification

• Start engine and verify ABS warning light extinguishes after initial bulb check (approximately 3 seconds)
• With engine running, apply firm brake pedal pressure and hold for 30 seconds - pedal should remain firm without sinking
• Check all brake line connections at ABS module for leaks while assistant holds firm pedal pressure
• Perform test drive in safe area starting with low speed (5-10 mph) stops to verify basic brake function
• Gradually increase speed and perform moderate stops from 20-30 mph to verify proper brake response
• Perform at least 3-4 ABS activation stops from 40 mph on dry pavement in safe area to verify ABS function and purge residual air
• After ABS stops, verify brake pedal still feels firm - re-bleed if pedal becomes soft
• Use scan tool to verify no ABS fault codes are present
• Check brake fluid level in master cylinder reservoir - top off if needed
• Re-check all brake line fittings and ABS module mounting bolts after test drive

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