STEP 1. Brake electric vacuum pump control relay 1 and 2 check.
STEP 2. Voltage measurement at PHEV-ECU connector (terminal VPM2).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Measure the voltage between the brake electric vacuum pump main relay connector (terminal VPM2) and body ground.OK: Approximately 12 volts (battery positive voltage).
Is the check result normal?
Go to Step 8. Go to Step 3.
STEP 3. Voltage measurement at brake electric vacuum pump main relay connector (terminal No.5).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Measure the voltage between the brake electric vacuum pump main relay connector (terminal No.5) and body ground.OK: Approximately 12 volts (battery positive voltage).
Is the check result normal?
Go to Step 5. Go to Step 4.
STEP 4. Check the power supply line for open circuit and short to ground circuit (fusible link No.8 and brake electric vacuum pump main relay).
STEP 5. Voltage measurement at brake electric vacuum pump control relay 1 and 2 connector (terminal No.5).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Measure between the connectors below and body ground. - Measure the voltage between the brake electric vacuum pump control relay 1 connector (terminal No.5) and body ground.
- Measure the voltage between the brake electric vacuum pump control relay 2 connector (terminal No.5) and body ground.
OK: Approximately 12 volts (battery positive voltage).
Is the check result normal?
Go to Step 7. Go to Step 6.
STEP 6. Check the power supply line for open circuit and short to ground circuit (brake electric vacuum pump main relay and brake electric vacuum pump control relay 1 or 2).
STEP 7. Check the signal line for open circuit and short circuit (brake electric vacuum pump control relay 1 or 2 and PHEV-ECU).
STEP 8. Voltage measurement at PHEV-ECU (terminals VPR1, VPR2) connector terminal.
(1) Measure the PHEV-ECU connector side by backprobing.
(2) Measure the voltage between the PHEV-ECU connector (terminals VPR1, VPR2) and body ground.OK: Approximately 12 volts (battery positive voltage).
Is the check result normal?
Go to Step 12. Go to Step 9.
STEP 9. Voltage measurement at brake electric vacuum pump control relay 1 and 2 connector (terminal No.3).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Measure between the connectors below and body ground. - Measure the voltage between the brake electric vacuum pump control relay 1 connector (terminal No.3) and body ground.
- Measure the voltage between the brake electric vacuum pump control relay 2 connector (terminal No.3) and body ground.
OK: Approximately 12 volts (battery positive voltage).
Is the check result normal?
Go to Step 11. Go to Step 10.
STEP 10. Check the power supply line for open circuit and short circuit (IGCT control relay and brake electric vacuum pump control relay 1 or 2).
STEP 11. Check the power supply line for open circuit and short circuit (brake electric vacuum pump control relay 1 or 2 and PHEV-ECU).
STEP 12. Using scan tool (M.U.T.-IIISE), check whether the DTC is set again.
Recheck the DTC.(1) Erase the DTC.
(2) Turn off the power supply mode of the electric motor switch.
(3) Depress the brake pedal, and turn on the power supply mode of the electric motor switch (READY operation).
(4) Check the DTC.
Is the DTC set?
Replace the PHEV-ECU (Refer to ). The procedure is complete.