Inspection Procedure

INSPECT BRAKE BOOSTER ACCUMULATOR ASSEMBLY
1. Turn the ignition switch OFF, and depress the brake pedal 40 times or more.
  HINT:
  
  When pressure in the power supply system is released, the brake pedal becomes easier to depress.
2. Install the LSPV gauge (SST) to the rear brake caliper and bleed air.
  SST 09709-29018
3. Depress the brake pedal with a force of more than 343 N (35 kgf, 77 lbf) and turn the ignition switch ON. Then check the rear brake caliper pressure when the increase in pressure changes from a sudden to a gradual increase.
  Standard pressure: 5,099 to 8,924 kPa (52 to 91 kgf/cm ² , 740 to 1,294 psi) at 20°C (68°F)
  
  HINT:
  
  If the value is not within the standard, cool the engine room and check it again.
NG: REPLACE BRAKE BOOSTER ACCUMULATOR ASSEMBLY

OK: Go to Next Step
CHECK BRAKE BOOSTER PUMP ASSEMBLY
1. Disconnect the B1 and B2 actuator connectors.
2. Connect the battery positive (+) leads to terminals 2 (BM1) and 3 (BM2) of the actuator (pump motor) connector and battery negative (-) leads to terminals 1 (EM1) and 6 (EM2).
  OK: Operation sound of pump motor can be heard.
NG: Go to step 6

Fig 1: Checking Brake Booster Pump Assembly
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step
CHECK BRAKE BOOSTER PRESSURE SWITCH (PH)
1. Turn the ignition switch OFF, and depress the brake pedal 40 times or more.
  HINT:
  
  When pressure in the power supply system is released, the brake pedal becomes easier to depress.
2. Install the LSPV gauge (SST) to the rear brake caliper and bleed air.
  SST 09709-29018
3. While checking the voltage between terminals PH and PHG of the brake master cylinder, depress the brake pedal with a force of more than 343 N (35 kgf, 77 lbf) and turn the ignition switch ON. Then check the rear wheel cylinder pressure when voltage changes from 6 V to 0 V.
  Standard pressure: 12,553 to 20,104 kPa (128 to 205 kgf/cm ² , 1,820 to 2,916 psi)
  
  Fig 2: Checking Brake Booster Pressure Switch (PH)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Turn the ignition switch OFF and disconnect the B1 connector from the brake actuator.
5. While checking the resistance between terminals PH and PHG, depress the brake pedal, changing the force in the range of 197 N (20 kgf, 44 lbf) to 343 N (35 kgf, 77 lbf), and check the rear wheel cylinder pressure when the resistance between terminals PH and PHG changes from 0 kΩ to 1 kΩ.
  Standard pressure: 11,964 to 18,240 kPa (122 to 186 kgf/cm ² , 1,735 to 2,645 psi)
  
  HINT:
  
  After the inspection, connect the connector, fill the brake reservoir with brake fluid and clear the DTC (see DTC CHECK / CLEAR ).
OK: Go to step 5

Fig 3: Checking Brake Booster Pressure Switch (PH)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to Next Step

CHECK WIRE HARNESS (BRAKE ACTUATOR - SKID CONTROL ECU AND BODY GROUND)

Fig 4: Checking Wire Harness (Brake Actuator - Skid Control ECU And Body Ground)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the B1 and B2 actuator connectors.
Disconnect the S5 and S8 ECU connectors.

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
S5-9 (PL) - B2-4 (PL)	Below 1 Ω
S8-11 (PH) - B1-3 (PH)	Below 1 Ω
B1-5 (PHG) - Body ground	Below 1 Ω
B2-2 (PLG) - Body ground	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR

OK: REPLACE BRAKE ACTUATOR

CHECK BRAKE BOOSTER PRESSURE SWITCH (PL)
1. Turn the ignition switch OFF, and depress the brake pedal 40 times or more.
  HINT:
  
  When pressure in the power supply system is released, the brake pedal becomes easier to depress.
2. Install the LSPV gauge (SST) to the rear brake caliper and bleed air.
  SST 09709-29018
3. Disconnect the B2 connector from the brake actuator.
4. While checking the resistance between terminals PL and PLG of the brake actuator, depress the brake pedal with a force of more than 343 N (35 kgf, 77 lbf) and turn the ignition switch ON. Then check the rear wheel cylinder pressure when the resistance changes from 5.7 kΩ to 1.0 kΩ.
  Standard pressure: 9,022 to 15,102 kPa (92 to 154 kgf/cm ² , 1,308 to 2,190 psi)
  
  Fig 5: Checking Brake Booster Pressure Switch (PL)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Turn the ignition switch OFF and disconnect the B2 connector from the brake actuator.
6. While checking the resistance between terminals PL and PLG of the brake actuator, depress the brake pedal, changing the force in the range of 197 N (20 kgf, 44 lbf) to 343 N (35 kgf, 77 lbf), and check the rear wheel cylinder pressure when the resistance between terminals PL and PLG changes from 1.0 kΩ to 5.7 kΩ.
  Standard pressure: 8,532 to 13,337 kPa (87 to 136 kgf/cm ² , 1,237 to 1,934 psi)
  
  HINT:
  
  After the inspection, connect the connector, fill the brake reservoir with brake fluid and clear the DTC (see DTC CHECK / CLEAR ).
NG: REPLACE BRAKE ACTUATOR

OK: REPLACE SKID CONTROL ECU
CHECK BRAKE CONTROL WIRE (BRAKE ACTUATOR - BRAKE BOOSTER PUMP MOTOR)
1. Remove the brake control wire.
2. Measure the resistance of the brake control wire.
  Standard resistance: Below 1 Ω
NG: REPLACE BRAKE CONTROL WIRE

OK: Go to Next Step
CHECK BRAKE BOOSTER PUMP ASSEMBLY
1. Check the brake booster pump motor operation.
  OK: Operation sound of motor can be heard.
NG: REPLACE BRAKE BOOSTER PUMP ASSEMBLY

OK: REPLACE BRAKE ACTUATOR