Removal & Installation
- Turn ignition to the "OFF" position and disconnect the negative battery cable.
Disconnect the ECU connectors from the ECU assembly.
WARNINGDo not apply a 12 volt power source to any terminal of the ECU connector when disconnected.
Mark the brake lines going into and out of the HCU with tags so reinstallation of the brake lines will be correct.
NOTEBefore removing the brake lines from HCU, the HCU must be thoroughly cleaned to prevent dirt particles from falling into the ports of HCU or entering the brake lines.
- Remove the brake lines from the HCU.
- Remove the bolts attaching the HECU bracket to the fender.
- Remove the HECU and bracket from vehicle.
- Remove the mounting pin and grommet attaching the HECU to the bracket and remove HECU from bracket.
- Remove the bolts securing the ECU to the HCU and lift the ECU carefully off the HCU.
- Inspect the seal on the ECU to ensure there are no nicks or cracks. If any signs of deterioration are present, replace the seal before proceeding.
- Carefully replace ECU on the replacement HCU.
Torque the ECU bolts in the following two steps as follows:
- Start all bolts into the HCU and hand tighten.
- Torque in the sequence shown until a final torque of 3 ft. lbs. (4 Nm) is achieved for each bolt.
- Reattach the bracket to the HECU mounting pin and grommet. Tighten the bracket mounting bolts to 11 ft. lbs. (15 Nm).
Reinstall bolts and nuts attaching the mounting bracket to the fender. Tighten the fasteners to 12 ft. lbs. (16 Nm).
NOTEWhen installing the brake lines on the HCU valve block, they must be located correctly in the valve block to ensure proper ABS operation.
- Attach brake lines to HECU, be careful to reattach the lines in the same positions which they were in prior to removal. Tighten each line to 12 ft. lbs. (16 Nm).
- Reconnect the ECU harness connectors.
- Connect the negative battery cable.
- Following proper procedures, bleed the brake system.
Road test vehicle to ensure proper operation of the base and ABS systems.