This procedure covers removal and replacement of the ABS hydraulic unit (pump and modulator assembly) on a 2018-2024 Toyota Camry with 2.5L I4 engine, including brake line disconnection, system bleeding, and verification.

Warnings

Tools required

Parts

• ABS hydraulic unit assembly × 1 — 44050-06180 or equivalent OEM
• Brake line sealing washers × 6 — Use OEM specification
• DOT 3 Brake Fluid × 1 — Use OEM specification

Fluids

• DOT 3 Brake Fluid — 1 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Disconnect negative battery terminal and wait 90 seconds for airbag system to discharge
3. Remove engine cover if equipped
4. Use turkey baster or fluid pump to remove most brake fluid from master cylinder reservoir to prevent overflow during line removal
5. Raise front of vehicle and secure on jack stands
6. Remove both front wheels to access brake components for later bleeding

Procedure

1. 1

   Locate and access ABS unit
   The ABS hydraulic unit is located in the left front corner of the engine bay, near the brake master cylinder. Remove the plastic engine bay covers and air intake components as needed to access the unit. On some models, you may need to remove the battery or battery tray for better access.
2. 2

   Disconnect ABS electrical connectors
   Locate the two electrical connectors on the ABS unit: the pump motor connector (larger, usually black) and the valve body connector (smaller, usually gray). Press the locking tabs and disconnect both connectors. Move the wiring harness aside to prevent damage during removal.
3. 3

   Label and disconnect brake lines
   Using a line wrench, carefully loosen the six brake line fittings connected to the ABS unit. Label each line with tape or take a photo to ensure correct reconnection. There are typically four lines from the master cylinder inlet side and two outlet lines to the wheel circuits. Have a drain pan positioned below and rags ready to catch fluid. Immediately cap or plug the open lines to prevent contamination and further fluid loss.
   ⚠Use only a line wrench to prevent rounding of the soft brake line fittings. Standard open-end wrenches will likely cause damage.
4. 4

   Remove ABS unit mounting nuts
   Locate the mounting nuts securing the ABS unit to its bracket (typically two or three 12mm nuts). Remove these nuts while supporting the weight of the ABS unit, as it will be free once the fasteners are removed. Note the position of any ground wires or brackets that may be secured by these nuts.
   Torque spec

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

   Remove ABS unit from vehicle
   Carefully lift the ABS unit out of the engine bay, tilting as needed to clear surrounding components. Keep the unit upright to minimize fluid spillage. Place the old unit in a drain pan and allow remaining fluid to drain. Inspect the mounting bracket and clean any corrosion or debris.
6. 6

   Prepare new ABS unit
   Unpack the new ABS hydraulic unit and verify all electrical connectors and brake line ports match the original. Remove protective caps from the brake line ports on the new unit. Install new sealing washers on each brake line fitting (do not reuse old washers as they will leak).
7. 7

   Install new ABS unit
   Position the new ABS unit into the mounting bracket, ensuring it seats properly and aligns with the mounting holes. Install the mounting nuts finger-tight first, then torque to specification. Reinstall any ground wires or brackets in their original positions.
   Torque spec

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

   Reconnect brake lines
   Thread each brake line fitting into the correct port on the ABS unit by hand first to prevent cross-threading. Once all fittings are hand-tight and confirmed to be threading correctly, use a line wrench to torque each fitting to specification in a criss-cross pattern to ensure even seating of the unit.
   ⚠Do not overtighten brake line fittings. Exceeding torque specification can crack the ABS unit body or damage the fitting threads.
   Torque spec

   Line Fittings20 Nm (15 lb-ft)
9. 9

   Reconnect electrical connectors
   Connect both electrical connectors to the ABS unit, ensuring they click firmly into place. Verify the locking tabs are fully engaged. Route the wiring harness to prevent contact with hot or moving engine components.
10. 10

    Fill brake fluid reservoir
    Fill the brake master cylinder reservoir to the MAX line with fresh DOT 3 brake fluid. Keep the reservoir topped off throughout the bleeding process to prevent air from entering the system.
11. 11

    Bleed brake system
    Bleed the brake system starting with the wheel farthest from the master cylinder (right rear), then left rear, right front, and left front. At each wheel, attach a clear hose to the bleeder screw and submerge the other end in a container of clean brake fluid. Have an assistant pump the brake pedal 3-4 times and hold, then open the bleeder screw to release fluid and air. Close the bleeder before the pedal reaches the floor. Repeat until no air bubbles appear. Torque each bleeder screw after bleeding that corner.
    ⚠Check and refill the brake fluid reservoir after bleeding each wheel. Never let it run dry or you must start the bleeding process over.
    Torque spec

    Bleeder Screw10 Nm (7 lb-ft)
12. 12

    Perform ABS pump bleed procedure
    If you have an OBD-II scan tool with ABS bleeding capability, connect it and follow the prompts to activate the ABS pump and cycle the internal valves while bleeding. This removes air trapped in the ABS unit itself. If a scan tool is not available, the system can self-bleed through normal initialization during the first several brake applications, but this method is less thorough.
13. 13

    Reinstall wheels and lower vehicle
    Reinstall both front wheels and torque lug nuts in a star pattern to specification. Lower the vehicle to the ground. Reconnect the negative battery terminal.
    Torque spec

    Wheel Lug Nuts140 Nm (103 lb-ft)

Reassembly

1. Reinstall any air intake components, battery, or engine covers that were removed for access
2. Verify all electrical connectors are fully seated and locked
3. Check brake fluid level and top off to MAX line if needed
4. Wipe down any brake fluid residue from painted surfaces and wash with water

Verification

• With engine off, pump brake pedal several times - it should build pressure and become firm. If pedal is soft or goes to floor, further bleeding is required
• Start engine and verify ABS warning light illuminates for approximately 3 seconds then turns off. If light stays on, scan for trouble codes
• Test drive in a safe area, performing several gentle stops from 20-30 mph to allow the ABS system to self-initialize
• Verify normal brake pedal feel and operation during test drive
• After test drive, recheck brake fluid level and inspect all brake line connections for leaks
• Perform a controlled ABS activation in a safe area (if conditions permit) to verify ABS pump operation
• If ABS light remains on or brake pedal is soft, a professional scan tool may be required to complete bleeding and clear codes

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