Code No. P1A46: Detection Circuit Of Main Battery Ground Fault Detector Abnormal












TROUBLE JUDGMENT


Check Conditions
  • 3.5 seconds elapse after the electric motor switch is turned ON, or 2 seconds elapse after the main battery starts to be charged.
  • Not while ground fault is prevented from being detected (not during the quick charge).
Judgement Criterion
  • If the main battery ground fault detector input is not turned ON within 5.5 seconds after the pre-check signal is turned ON from OFF.
or

  • If the main battery ground fault detector input is not turned OFF within 2.5 seconds after the pre-check signal is turned OFF from ON.

FAIL-SAFE AND BACKUP FUNCTION



  • Not available

PROBABLE CAUSES



  • Ground fault of high voltage system component.
  • The main battery ground fault detector is failed.
  • Open circuits of main battery ground fault detector circuit, short circuits to earth, short circuits to power supply system or damage; poor contact of connector.
  • The BMU is failed.

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III diagnosis code


Q. Is the diagnosis code of P1A44 set?

Check detecting ground fault (Code No. P1A44: Detecting Ground Fault ).
Go to Step 2 .

STEP 2. Connector check: C-22 main battery connector


Q. Is the check result normal?

Go to Step 3
Repair.

STEP 3. Perform voltage measurement at C-22 main battery connector



  • Disconnect connector, and measure at harness side.
  • Electric motor switch: ON
  • Voltage between terminal No. 4 and earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 5 .
Go to Step 4 .

STEP 4. Connector check: A-08X EV control relay connector


Q. Is the check result normal?


    Check intermediate connectors B-27, C-102 and C-112, and repair if necessary. If intermediate connectors are normal, check and repair harness between A-08X (terminal No. 1) EV control relay connector and C-22 (terminal No. 4) main battery connector.

    • Check power supply line for open/short circuit.
Repair.

STEP 5. Perform resistance measurement at C-22 main battery connector



  • Disconnect connector, and measure at harness side.
  • Resistance between terminal No. 5 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?

Go to Step 6 .

    Check and repair harness between C-22 (terminal No. 5) main battery connector and body earth.

    • Check earthing line for open circuit and damage.

STEP 6. Connector check: C-21 main battery connector


Q. Is the check result normal?

Go to Step 7 .
Repair.

STEP 7. Perform resistance measurement at C-21 main battery connector



  • Disconnect connector, and measure at harness side.
  • Resistance between terminal No. 6 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?

Go to Step 8 .

    Check intermediate connector C-104, and repair if necessary. If intermediate connector is normal, check and repair harness between C-21 (terminal No. 6) main battery connector and body earth.

    • Check earthing line for open circuit and damage.

STEP 8. Connector check: A-08X EV control relay connector


Q. Is the check result normal?

Go to Step 9 .
Repair.

STEP 9. Check harness between A-08X (terminal No. 1) EV control relay connector and C-22 (terminal No. 4) main battery connector.


note Before checking harness, check intermediate connectors B-27, C-102 and C-112, and repair if necessary.

  • Check power supply line for damage.

Q. Is the check result normal?

Go to Step 10 .
Repair.

STEP 10. Connector check: C-109 BMU connector


Q. Is the check result normal?

Go to Step 11 .
Repair.

STEP 11. Perform voltage measurement at C-109 BMU connector



  • Measure BMU terminal voltage.
  • Disconnect C-21 main battery connector.
  • Electric motor switch: ON
  • Voltage between terminal No. 35 and earth.
OK: 0 - 0.1 V

Q. Is the check result normal?

Go to Step 12 .

    Check and repair harness between C-109 (terminal No. 35) BMU connector and C-21 (terminal No. 5) main battery connector.

    • Check output line for short circuit to power supply.

STEP 12. Check harness between C-21 (terminal No. 5) main battery connector and C-109 (terminal No. 35) BMU connector



  • Check output line for open circuit, short circuit to earth and damage.

Q. Is the check result normal?

Go to Step 13 .
Repair.

STEP 13. Check harness between C-21 (terminal No. 7) main battery connector and C-109 (terminal No. 46) BMU connector.



  • Check signal line for open circuit, short circuit to earth, short circuit to power supply system and damage.

Q. Is the check result normal?

Go to Step 14
Repair.

STEP 14. Perform voltage measurement at C-109 BMU connector



  • Measure BMU terminal voltage.
  • Electric motor switch: "LOCK" (OFF) → ON
  • Voltage between terminal No. 46 and earth.
OK: 5.3 V or more → 1 V or less (After several seconds elapse)

Q. Is the check result normal?

Go to Step 15 .
Replace the BMU.

STEP 15. Perform voltage measurement at C-109 BMU connector



  • Measure BMU terminal voltage.
  • Electric motor switch: "LOCK" (OFF) → ON
  • Voltage between terminal No. 35 and earth.
OK: 8 V or more → 1.3 V or less (After several seconds elapse)

Q. Is the check result normal?

Replace the BMU.
Go to Step 16 .

STEP 16. M.U.T.-III diagnosis code.


Q. Is the diagnosis code set?

Replace the main battery.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).