Inspection Procedure 2: Charge warning lamp of auxiliary battery lit in READY status




COMMENT ON TROUBLE SYMPTOM



  • When detects abnormalities, the DC-DC converter should send the signal to the PHEV-ECU. The PHEV-ECU receives the signal and then lights the charge warning lamp of the auxiliary battery of the combination meter.
  • If the charge warning lamp of the auxiliary battery is lit in the READY state, the DC-DC converter can be failed, or the circuit of the DC-DC converter would be failed.

PROBABLE CAUSES



  • The auxiliary battery is failed.
  • The on board charger/DC-DC converter is failed.
  • Open circuits of DC-DC converter, short circuits to earth or damage; poor contact of connector
  • The PHEV-ECU is failed.

DIAGNOSIS PROCEDURE


danger When high voltage system components are served, be sure to pull service plugs to shut down high voltage (Refer to ).
danger When pulling service plugs, wear the specified protective equipment (Refer to ).

STEP 1. Check auxiliary battery



  • Connect the M.U.T.-III to the diagnosis connector.
  • Check auxiliary battery (Refer to GROUP 54A - Auxiliary Battery - On-vehicle Service - Battery Test ).

Q. Is the check result normal?

Go to Step 2.
Replace the auxiliary battery.

STEP 2. Voltage measurement at fusible link box.


(1)Ready indicator is illuminated.
(2)Check the voltage fuse (120 A) terminal of terminal No. 26 and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 3.
Go to Step 7.

STEP 3. Voltage measurement at on board charger/DC-DC converter connector (S terminal).


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Ready indicator is illuminated.
(3)Check the voltage between the on board charger/DC-DC converter connector (S terminal) and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 5.
Go to Step 4.

STEP 4. Check of short to earth, and open circuit in S line between auxiliary battery and on board charger/DC-DC converter connector.


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 ).
Repair the connector(s) or wiring harness.

STEP 5. Check of damage in S line between auxiliary battery and on board charger/DC-DC converter connector.


Q. Is the check result normal?

Go to Step 6.
Repair the connector(s) or wiring harness.

STEP 6. Check the trouble symptom


Q. Does the trouble symptom persist?

Replace the on board charger/DC-DC converter.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 7. Resistance measurement at on board charger/DC-DC converter connector (CGND terminal).


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the on board charger/DC-DC converter connector (CGND terminal) and body earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?

Go to Step 8.
Repair CGND line between on board charger/DC-DC converter connector and body earth

STEP 8. Voltage measurement at on board charger/DC-DC converter connector (IGCT terminal).


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Power supply mode of electric motor switch: ACC
(3)Check the voltage between the on board charger/DC-DC converter connector (IGCT terminal) and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 9.
Repair IGCT line between IGCT control relay connector and on board charger/DC-DC converter connector.

STEP 9. Check of damage in IGCT line between IGCT control relay connector and on board charger/DC-DC converter connector.


Q. Is the check result normal?

Go to Step 10.
Repair the connector(s) or wiring harness.

STEP 10. Check of damage in DCSW line between PHEV-ECU connector and on board charger/DC-DC converter connector.


Q. Is the check result normal?

Go to Step 11.
Repair the connector(s) or wiring harness.

STEP 11. Check of short to earth, open circuit and damage in +B line between auxiliary battery connector and engine-ECU connector.


Q. Is the check result normal?

Go to Step 12.
Repair the connector(s) or wiring harness.

STEP 12. Perform the continuity check of the high voltage fuse inside the RMCU.



danger When high voltage system components are served, be sure to pull service plugs to shut down high voltage before serving (Refer to ).
danger When pulling service plugs, wear the specified protective equipment (Refer to ).

  • Check continuity of high voltage fuse both ends.
OK: Continuity

Q. Is the check result normal?

Go to Step 13.

Replace the high voltage fuse.

STEP 13. Check of open circuit and damage in P line and N line between on board charger/DC-DC converter connector and drive battery connector.


Q. Is the check result normal?

Go to Step 6.
Repair the connector(s) or wiring harness.