[Previous][Next]
DTC C2018: Control relay1 stuck OFF (VP)
DTC C2019: Control relay2 stuck OFF (VP)
 
 
cautionWhenever ECU is replaced, ensure that the CAN bus lines are normal.
 
 
DTC SET CONDITIONS
The PHEV-ECU sets DTCs C2018 or C2019 when the brake electric vacuum pump control relay 1 or 2 is stuck off.
 
 
 
PROBABLE CAUSES
  • Malfunction of the brake electric vacuum pump control relay 1 or 2.
  • Malfunction of the brake electric vacuum pump relay box.
  • Damaged harness or connector.
  • Malfunction of the PHEV-ECU.
 
 

 
 
DIAGNOSIS
Required Special Tools
  • MB991223: Wiring harness set
  • MB992006: Extra fine probe
STEP 1. Brake electric vacuum pump control relay 1 and 2 check.
Refer to GROUP 35A - On-vehicle Service, Relay Check .
Is the check result normal?
Go to Step 2.
Replace the only defective brake electric vacuum pump control relay 1 or 2.
 
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 PHEV-ECU 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).
Fusible link No.8 and brake electric vacuum pump main relay connector (terminal No.5).
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
Repair the connector or wiring harness.
 
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.
When the DTC C2018 is set.
  • Measure the voltage between the brake electric vacuum pump control relay 1 connector (terminal No.4) and body ground.
OK: Approximately 12 volts (battery positive voltage).
When the DTC C2019 is set.
  • Measure the voltage between the brake electric vacuum pump control relay 2 connector (terminal No.4) 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).
When the DTC C2018 is set.
  • Brake electric vacuum pump main relay connector (terminal No.4) and brake electric vacuum control relay 1 connector (terminal No.5).
When the DTC C2019 is set.
  • Brake electric vacuum pump main relay connector (terminal No.4) and brake electric vacuum control relay 2 connector (terminal No.5).
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
Repair the connector or wiring harness.
 
STEP 7. Check the signal line for open circuit and short to ground circuit (brake electric vacuum pump control relay 1 or 2 and PHEV-ECU).
Check the following wiring harness wires.
When the DTC C2018 is set.
  • Brake electric vacuum pump control relay 1 connector (terminal No.4) and PHEV-ECU connector (terminal VPM2).
When the DTC C2019 is set.
  • Brake electric vacuum pump control relay 2 connector (terminal No.4) and PHEV-ECU connector (terminal VPM2).
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
Repair the connector or wiring harness.
 
STEP 8. Voltage measurement at PHEV-ECU connector (terminals VPR1, VPR2).
(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.
When the DTC C2018 is set.
  • Measure the voltage between the brake electric vacuum pump control relay 1 connector (terminal No.3) and body ground.
OK: Approximately 12 volts (battery positive voltage).
When the DTC C2019 is set.
  • 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 to ground circuit (IGCT control relay and electric vacuum pump control relay 1 or 2).
Check the following wiring harness wires.
When the DTC C2018 is set.
  • Check the wiring harness between IGCT control relay and the electric vacuum pump control relay 1 connector (terminal No.3).
When the DTC C2019 is set.
  • Check the wiring harness between IGCT control relay and the electric vacuum pump control relay 2 connector (terminal No.3).
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
Repair the connector or wiring harness.
 
STEP 11. Check the power supply line for open circuit and short to ground circuit (Electric vacuum pump control relay 1 or 2 and PHEV-ECU).
Check the following wiring harness wires.
When the DTC C2018 is set
  • Brake electric vacuum pump control relay 1 connector (terminal No.1) and PHEV-ECU connector (terminal VPR1).
When the DTC C2019 is set
  • Brake electric vacuum pump control relay 2 connector (terminal No.1) and PHEV-ECU connector (terminal VPR2).
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
Repair the connector or wiring harness.
 
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.