Inspection Procedure

WARNING: This page is about a different car, the 2005 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.

Check accumulator operation.
PREPARATION:
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, reaction force becomes light and stroke becomes longer.
2. Install the LSPV gauge (SST) to the rear brake caliper and bleed air. SST 09709-29018
  CHECK:
  
  Depress the brake pedal with a force of more than 294 N (30 kgf, 66 lbf) and turn the ignition switch ON, then check the rear brake caliper pressure when an increase of pressure changes from acutely to mildly.
  
  OK:
  
  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.
1. NG: Replace accumulator.
2. OK: Go to next step.
Check operation of hydraulic brake booster pump motor.
PREPARATION:

Disconnect the 2 connectors from the hydraulic brake booster.

CHECK:

Connect the battery positive (+) lead to BM1 or BM2 terminal and the battery negative (-) lead to EM1 or EM2 terminal of the hydraulic brake booster (pump motor) connector.

OK:

The operation sound of the pump motor should be heard.

Fig 1: Checking Operation Of Hydraulic Brake Booster Pump Motor
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. NG: Go to step 7 .
2. OK: Go to next step.
Check pressure switch (PH) operation.
PREPARATION:
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, reaction force becomes light and stroke becomes longer.
2. Install the LSPV gauge (SST) to the rear brake caliper and bleed air.
  SST 09709-29018
  
  CHECK:
  
  While checking the voltage between terminals PH and PHG of the hydraulic brake booster, depress the brake pedal with a force of more than 294 N (30 kgf, 66 lbf) and turn the ignition switch ON, then check the rear wheel cylinder pressure when voltage changes from 6 V to 0 V.
  
  OK:
  
  12,553 to 20,104 kPa (128 to 205 kgf/cm ² , 1,820 to 2,916 psi)
  
  Fig 2: Checking Voltage Between Terminals PH & PHG Of Hydraulic Brake Booster (1 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  PREPARATION:
  
  Turn the ignition switch OFF and disconnect the connector (5P) from the hydraulic brake booster.
  
  CHECK:
  
  While checking the resistance between terminals PH and PHG, depress the brake pedal changing the force in a range of 197 N (20 kgf, 44 lbf) to 294 N (30 kgf, 66 lbf) and check the rear wheel cylinder pressure when resistance changes from 0 kΩ to 1 kΩ between PH and PHG.
  
  OK:
  
  11,964 to 18,240 kPa (122 to 186 kgf/cm ² , 1,735 to 2,645 psi)
  
  HINT:
  
  After inspection, connect the connector, fill brake reservoir with brake fluid and clear the DTC (See PRE-CHECK ).
  
  Fig 3: Checking Voltage Between Terminals PH & PHG Of Hydraulic Brake Booster (2 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. OK: Go to step 5 .
2. NG: Go to next step.
Check for open circuit in harness and connector between pressure switch (PH) and skid control ECU (See HOW TO USE THE DIAGNOSTIC TABLE AND INSPECTION ).
1. NG: Repair or replace harness or connector.
2. OK: Replace hydraulic brake booster assembly.
Check pressure switch (PL) operation.
PREPARATION:
1. Turn the motor switch OFF, and depress the brake pedal 40 times or more.
  HINT:
  
  When pressure in the power supply system is released, reaction force becomes light and stroke becomes longer.
2. Install the LSPV gauge (SST) to the rear brake caliper and bleed air.
  SST 09709-29018
3. Disconnect the connector (8P) from the hydraulic brake booster.
  CHECK:
  
  While checking the resistance between terminals PL and PLG of the hydraulic brake booster, depress the brake pedal with a force of more than 294 N (30 kgf, 66 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.
  
  OK:
  
  9,022 to 15,102 kPa (92 to 154 kgf/cm ² , 1,308 to 2,190 psi)
  
  PREPARATION:
  
  Turn the ignition switch OFF and disconnect the connector (8P) from the hydraulic brake booster.
  
  CHECK:
  
  While checking the resistance between terminals PL and PLG of the hydraulic brake booster, depress the brake pedal changing the force in a range of 197 N (20 kgf, 44 lbf) to 294 N (30 kgf, 66 lbf) and check the rear wheel cylinder pressure when resistance changes from 1.0 kΩ to 5.7 kΩ.
  
  OK:
  
  8,532 to 13,337 kPa (87 to 136 kgf/cm ² , 1,237 to 1,934 psi)
  
  Fig 4: Checking Resistance Between Terminals PL & PLG Of Hydraulic Brake Booster
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  
  After inspection, connect the connector, fill brake reservoir with brake fluid and clear the DTC (See PRE-CHECK ).
1. NG: Replace hydraulic brake booster assembly.
2. OK: Go to next step.
Check pressure switch (PH) and pressure switch (PL)
CHECK:

Compare the pressure value of the rear wheel cylinder measured in check pressure switch (PL) operation with the one measured in check pressure switch (PH) operation.

OK:
- Pressure when the voltage between PH and PHG becomes 6 to 0 V > pressure when the resistance between PL and PLG becomes 5.7 kΩ to 1.0 kΩ.
- Pressure when the resistance between PH and PHG becomes 0 kΩ to 1 kΩ > pressure when the resistance between PL and PLG becomes 1.0 kΩ to 5.7 kΩ.
1. NG: Replace hydraulic brake booster assembly.
2. OK: Check and replace skid control ECU.
Check for open or short circuit in harness and connector between hydraulic brake booster pump motor and hydraulic brake booster (See HOW TO USE THE DIAGNOSTIC TABLE AND INSPECTION ).
1. NG: Replace wire harness.
2. OK: Go to next step.
Check hydraulic brake booster pump motor (See INSPECTION ).
1. NG: Replace hydraulic brake booster pump motor.
2. OK: Replace hydraulic brake booster.