Code No. B1108 Electric water heater fail 1




DIAGNOSIS CODE SET CONDITIONS


This code is stored when the outlet temperature of the heater does not raise to a temperature higher than the inlet temperature by 3°C or more for 30 seconds or more.

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


STEP 1. Check the engine coolant level.


Check the engine coolant level (Refer to GROUP14A - On-vehicle Service, Engine coolant level check ).

Q. Is the engine coolant level correct?

Go to Step 2.
Check the engine coolant level, and add if necessary.

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


Check if diagnosis code is stored in the heater controller assembly (A/C-ECU).

  • DTC: B1115

Q. Is the diagnosis code stored?

Carry out the diagnosis code procedures. Refer to .
Go to Step 3.

STEP 3. Check the heater water pump assembly.


Check heater water pump assembly.

Q. Is the water heater fluid confirmed?

Go to Step 7.
NO <No heater water pump assembly running noise can be heard> : Go to Step 4.
NO <A heater water pump assembly running noise can be heard, but the water heater fluid cannot be confirmed> : Replace the heater water pump assembly.

STEP 4. Measure the resistance at heater water pump assembly connector.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Resistance between the heater water pump assembly earth terminal and body earth
OK: Continuity exists (2 Ω or less).

Q. Is the check result normal?

Go to Step 6.
Go to Step 5.

STEP 5. Check of open circuit in earth line between heater water pump assembly and earth 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 6. Check the heater water pump assembly.


Refer to .

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 heater water pump assembly.

STEP 7. M.U.T.-III actuator test, service data


Check the results of the actuator test with the service data.
Actuator test
  • Item 1: ELC.water heater test mode
Data list
  • Item197: ELC.water heater test status
note Because actuator test "item1: ELC. water heater test mode" checks variations in the current, turn OFF other electric equipment before the test.

Q. Is the check result normal?

Go to Step 8.
Go to Step 11.

STEP 8. M.U.T.-III data list


Check that the following service data display contents are normal.

  • Item 170: ELC.water heater inlet sensor
  • Item 171: ELC.water heater outlet sensor

Q. Is the check result normal?

Go to Step 13.
NO : Go to Step 9.

STEP 9. Check the heater outlet water temperature sensor/heater inlet water temperature sensor.


Refer to .

Q. Is the check result normal?

Go to Step 10.
Replace the electric heater.

STEP 10. Check of open circuit in WTSI, WTSO, SENG line between electric heater connector and heater controller assembly (A/C-ECU) connector.


Q. Is the check result normal?

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

STEP 11. Check of open circuit in +12V, HTR1, HTR2, HTR3 line between electric heater connector and heater controller assembly (A/C-ECU) connector.


Q. Is the check result normal?

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

STEP 12. Check the high-voltage connector and wiring harness.


danger Carry out the check on the high-voltage circuit while reading carefully the precautions on handling a high-voltage vehicle. Refer to.
danger Wear the specified protection equipment during the check.
1.Shut down the high voltage. (Refer to GROUP 00 - Precautions before Service - Precautions on handling high-voltage vehicle .)
2. Check the heater connector.
3. Check the high-voltage fuse No. 5 connecting bolt for looseness.
4.Visually check and check the continuity of the high-voltage fuse No. 5.
5.Visually check the following high-voltage wiring harnesses for damage.

Q. Is the check result normal?

Go to Step 14.
NO <Malfunction of high-voltage fuse No. 5> : Replace the high-voltage fuse No. 5.
NO <Malfunction of wiring harness on heater side> : Replace the electric heater.
NO <Malfunction of wiring harness on RMCU side> : Repair the connector(s) or the wiring harness wire(s) at the RMCU side. Then go to Step 13.

STEP 13. M.U.T.-III other system diagnosis code


Check whether the RMCU-related diagnosis code is stored.

Q. Is the diagnosis code stored?

Diagnose the RMCU (Refer to GROUP 54D - Diagnosis code chart for electric motor control unit (EMCU) and electric motor unit ). Then go to Step 14.
Go to Step 14.

STEP 14. Check whether the diagnosis code is stored again.


Q. Is the diagnosis code stored?

Go to Step 15.
Intermittent malfunction. (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunctions .)

STEP 15. After replacing the A/C controller assembly, check again if the diagnosis code is stored.


Q. Is the diagnosis code stored?

Replace the electric heater.
This diagnosis is complete.