Inspection Procedure 14: Battery rundown <Vehicles with battery current sensor>












COMMENT ON TROUBLE SYMPTOM



  • Failure is possibly caused by failed alternator, failed generation control circuit or other faults.

PROBABLE CAUSES



  • Failed battery
  • Open/short circuit or harness damage in alternator L terminal circuit
  • Short circuit in alternator G terminal
  • Failed alternator
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery.

  • Check battery (Refer to GROUP 54A - Battery - On-vehicle Service - Battery Test ).

Q. Is the check result normal?
Go to Step 2 .
Replace the battery.

STEP 2. M.U.T.-III diagnosis code.

Q. Is the diagnosis code set?
Inspection chart for diagnosis code (Refer to ).
Go to Step 3 .

STEP 3. Connector check: B-20 intermediate connector

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

STEP 4. Perform voltage measurement at B-20 intermediate connector.

  • Disconnect connector, and measure at male connector side.
  • Ignition switch: ON
  • Voltage between terminal No. 3 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 7 .
Go to Step 5 .

STEP 5. Connector check: D-02 combination meter connector

Q. Is the check result normal?
Go to Step 6 .
Repair or replace the connector.

STEP 6. Check harness between B-20 (terminal No. 3) intermediate connector and D-02 (terminal No. 47) combination meter connector.
note Before checking harness, check intermediate connector D-230, and repair if necessary.

  • Check power supply line for open/short circuit.

Q. Is the check result normal?
Check the combination meter (Refer to GROUP 54A - Combination Meter - Trouble Symptom Chart ).
Repair the damaged harness wire.

STEP 7. Connector check: B-46 intermediate connector

Q. Is the check result normal?
Go to Step 8 .
Repair or replace the connector.

STEP 8. Perform voltage measurement at B-46 intermediate connector.

  • Disconnect connector, and measure at female connector side.
  • Ignition switch: ON
  • Voltage between terminal No. 6 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 14 .
Go to Step 9 .

STEP 9. Connector check: B-116 alternator connector

Q. Is the check result normal?
Go to Step 10 .
Repair or replace the connector.

STEP 10. Check harness between B-46 (terminal No. 6) intermediate connector and B-116 (terminal No. 1) alternator connector.

  • Check output line for short circuit.

Q. Is the check result normal?
Go to Step 11 .
Repair the damaged harness wire.

STEP 11. Check harness between B-20 (terminal No. 3) intermediate connector and B-116 (terminal No. 3) alternator connector.

  • Check power supply line for open/short circuit.

Q. Is the check result normal?
Go to Step 12 .
Repair the damaged harness wire.

STEP 12. Connector check: D-02 combination meter connector

Q. Is the check result normal?
Go to Step 13 .
Repair or replace the connector.

STEP 13. Check harness between B-116 (terminal No. 3) alternator connector and D-02 (terminal No. 47) combination meter connector.
note Before checking harness, check intermediate connector D-230, and repair if necessary.

  • Check power supply line for damage.

Q. Is the check result normal?
Check the alternator.
Repair the damaged harness wire.

STEP 14. Connector check: D-215 engine-ECU connector

Q. Is the check result normal?
Go to Step 15 .
Repair or replace the connector.

STEP 15. Perform voltage measurement at D-215 engine-ECU connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 121 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 16 .

    Check and repair harness between B-46 (terminal No. 6) intermediate connector and D-215 (terminal No. 121) engine-ECU connector.

    • Check output line for short circuit.

STEP 16. Perform voltage measurement at D-215 engine-ECU connector.

  • Measure engine-ECU terminal voltage.
  • Engine: Idling after warm-up
  • Transmission: Neutral <M/T> or P range <A/T>
  • Voltage between terminal No. 121 and earth.
OK: The voltage increases when the headlamp switch and the rear window defogger switch are turned ON from OFF.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Replace the engine-ECU. When the engine-ECU is replaced, write the chassis number (Refer to GROUP 00 - Precautions Before Service - How to Perform Chassis Number Writing ). After replacing the engine-ECU, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns ). After registering the injector identification code, the vehicle equipped with the closed type DPF carries out the forcible DPF regeneration. (Refer to GROUP 17 - Diesel Particulate Filter (DPF) System - Forcible DPF Regeneration ).