Inspection Procedure 17: Battery rundown








COMMENT ON TROUBLE SYMPTOM



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

PROBABLE CAUSES



  • Failed battery
  • Alternator G terminal short-circuited
  • Failed alternator
  • Failed engine-A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery voltage.

  • Measure battery voltage during cranking.
OK: 8 V or more

Q. Is the check result normal?
Go to Step 2 .
Check battery (Refer to GROUP 54A - Battery - On-vehicle Service - Battery test ).

STEP 2. Connector check: B-20 intermediate connector

Q. Is the check result normal?
Go to Step 3 .
Repair or replace the connector.

STEP 3. 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 5 .
Go to Step 4 .

STEP 4. Connector check: D-309 ignition switch connector

Q. Is the check result normal?

    Check intermediate connectors D-02, D-230, D-403 and D-405, and repair if necessary. If intermediate connectors are normal, check and repair harness between B-20 (terminal No. 3) intermediate connector and D-309 (terminal No. 2) ignition switch connector.

    • Check power supply line for open/short circuit.
Repair or replace the connector.

STEP 5. Perform voltage measurement at B-20 intermediate connector.

  • Disconnect connector, and measure at female connector side.
  • Ignition switch: ON
  • Voltage between terminal No. 5 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 10 .
Go to Step 6 .

STEP 6. Connector check: B-116 alternator connector

Q. Is the check result normal?
Go to Step 7 .
Repair or replace the connector.

STEP 7. Check harness between B-20 (terminal No. 5) 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 8 .
Repair the damaged harness wire.

STEP 8. 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 9 .
Repair the damaged harness wire.

STEP 9. Check harness between B-116 (terminal No. 3) alternator connector and D-309 (terminal No. 2) ignition switch connector.
note Before checking harness, check intermediate connectors D-02, D-230, D-403 and D-405, and repair if necessary.

  • Check power supply line for damage.

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

STEP 10. Connector check: D-214 engine-A/T-ECU connector

Q. Is the check result normal?
Go to Step 11 .
Repair or replace the connector.

STEP 11. Perform voltage measurement at D-214 engine-A/T-ECU connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 45 and earth.
OK: System voltage

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

    Check and repair harness between B-20 (terminal No. 5) intermediate connector and D-214 (terminal No. 45) engine-A/T-ECU connector.

    • Check output line for short circuit.

STEP 12. Perform voltage measurement at D-214 engine-A/T-ECU connector.

  • Measure engine-A/T-ECU terminal voltage.
  • Engine: Idling after warm-up
  • Transmission: P range
  • Voltage between terminal No. 45 and earth.
OK: Switching the headlamps to ON from OFF causes the voltage to increase by 0.2 - 3.5 V.

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

    Check the alternator.

STEP 13. Check the trouble symptom.

Q. Does trouble symptom persist?
Replace the engine-A/T-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).