Inspection Procedure 1: EV-ECU power supply system


HIGH VOLTAGE POWER SUPPLY CONTRPL SYSTEM CIRCUIT














PROBABLE CAUSES

  • Malfunction of the EV control relay
  • Malfunction of the EV-ECU
  • Open circuit, short circuit to earth system, damage, or connector poor contact in the EV-ECU circuit

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-106 EV-ECU connector

Q. Is the check result normal?
Go to Step 2.
Repair the damaged connector.

STEP 2. Voltage measurement at C-106 EV-ECU connector
(1)Disconnect the connector and measure at the wiring harness side.
(2)Turn the electric motor switch to the ON position.
(3)Measure the voltage between C-106 EV-ECU connector terminal No. 9 and the earth.
OK: Battery voltage
(4)Measure the voltage between the C-106 EV-ECU connector terminal No. 24 and the earth.
OK: Battery voltage

Q. Is the check result normal?
Go to Step 10.

    Go to Step 3.

STEP 3. Connector check: A-08X EV control relay connector

Q. Is the check result normal?
Go to Step 4.
Repair the damaged connector.

STEP 4. EV control relay check after it has been removed
Check the EV control relay after it has been removed. (Refer to .)

Q. Is the check result normal?
Go to Step 5.
Replace the EV control relay.

STEP 5. Measure the resistance at A-08X EV control relay.
(1)Disconnect the connector and measure at the wiring harness side.
(2)Measure the resistance between the A-08X EV control relay connector terminal No. 2 and the body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 7.
Go to Step 6.

STEP 6. Check the wiring harness between A-08X EV control relay connector terminal No. 2 and the body earth.
Check the earth wires for open circuit.
note Before the wiring harness check, check the B-122 earth connector, and repair if necessary.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Repair the wiring harness.

STEP 7. Measure the voltage at A-08X EV control relay connector.
(1)Disconnect the connector and measure at the wiring harness side.
(2)Measure the voltage between the A-08X EV control relay connector terminal No. 4 and the earth.
OK: Battery voltage

Q. Is the check result normal?
Go to Step 9.

    Go to Step 8.

STEP 8. Check the wiring harness between A-08X EV control relay connector terminal No. 4 and the fusible link No. 21.
Check the power supply line for open circuit and short circuit.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Repair the wiring harness.

STEP 9. Wiring harness check
Check the wiring harness below for open circuit and short circuit.

  • Between the A-08X EV control relay connector terminal No. 1 and C-106 EV-ECU connector terminal No. 9
  • Between the A-08X EV control relay connector terminal No. 1 and C-106 EV-ECU connector terminal No. 24
  • Between the A-08X EV control relay connector terminal No. 3 and C-106 EV-ECU connector terminal No. 2
note Prior to the wiring harness inspection, check B-27 intermediate connectors, and repair if necessary.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Repair the wiring harness.

STEP 10. Voltage measurement at C-106 EV-ECU connector
(1)Disconnect the connector and measure at the wiring harness side.
(2)Measure the voltage between the C-106 EV-ECU connector terminal No. 1 and the earth.
OK: Battery voltage

Q. Is the check result normal?
Go to Step 12.

    Go to Step 11.

STEP 11. Check the wiring harness between C-106 EV-ECU connector terminal No. 1 and the fusible link No. 25.
Check the power supply line for open circuit and short circuit.
note Before the wiring harness check, check B-301 and B-310 junction block connector, and repair if necessary.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Repair the wiring harness.

STEP 12. Measure the resistance at C-106 EV-ECU connector.
(1)Disconnect the connector and measure at the wiring harness side.
(2)Measure the resistance between the C-106 EV-ECU connector terminal No. 10 and the body earth.
OK: Continuity exists (2 Ω or less)
(3)Measure the resistance between the C-106 EV-ECU connector terminal No. 25 and the body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 14.
Go to Step 13.

STEP 13. Check the wiring harness between C-106 EV-ECU connector terminal No. 10 or 25 and the body earth.
Check the earth wires for open circuit.
note Before the wiring harness check, check the C-32 earth connector, and repair if necessary.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Repair the wiring harness.

STEP 14. Check the trouble symptom.
Check that the EV-ECU functions work normally.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Replace the EV-ECU.