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Inspection Procedure

NOTE: When replacing the master cylinder solenoid, perform zero point calibration (See CALIBRATION ).

HINT:

Remove the hydraulic brake booster assembly before the inspection (See REMOVAL ).

  1. CHECK CONNECTION OF PUMP MOTOR WIRE HARNESS 
    1. Using a screwdriver, remove the 2 plugs from the hydraulic brake booster assembly (See DISASSEMBLY ).
    2. Check the tightening torque of the 2 screws which tighten the wire harness connecting the hydraulic brake booster assembly and brake booster pump (See REASSEMBLY ).

    OK: The harness is tightened to the specific torque. Torque: 2.9 N*m (30 kgf*cm, 26 in.*lbf) 

    NG: RETIGHTEN SCREWS 

    OK: Go to next step 

  2. CHECK RESISTANCE OF PUMP MOTOR WIRE HARNESS 
    1. Using a screwdriver, remove the 2 screws and pull the wire harness from the hydraulic brake booster assembly.
    2. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    RESISTANCE SPECIFICATION

    Tester Connection Condition Specified Condition
    Red wire terminal - Black wire terminal Always 2 Ω

    NG: REPLACE BRAKE BOOSTER PUMP ASSEMBLY  (See DISASSEMBLY )

    Fig 1: Identifying Red & Black Wires
    G05629896Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  3. RECONFIRM DTC 
    1. Reassemble the hydraulic brake booster assembly (See INSPECTION ).
    2. Install the hydraulic brake booster assembly (See INSTALLATION ).
    3. Clear the DTC (See DTC CHECK/CLEAR ).
    4. Check if the same DTC is output (See DTC CHECK/CLEAR ).

    Result 

    RESULT REFERENCE

    Result Proceed to
    DTC is output. A
    DTC is not output. B

    B: USE SIMULATION METHOD TO CHECK  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    A: REPLACE MASTER CYLINDER SOLENOID  (See INSPECTION )