Inspection Procedure 8: Either of the door mirror heater elements does not work.


COMMENTS ON TROUBLE SYMPTOM
If one of the door mirror heater elements does not work, the power supply or earth to the element, or the element itself may be defective.

PROBABLE CAUSES

  • Door mirror heater elements failed
  • Wiring harness or connector failure

DIAGNOSTIC PROCEDURE

STEP 1. Determine a trouble spot.

Q. Which of door mirror heater elements does not work?
RH side door mirror : Go to Step 2.
LH side door mirror : Go to Step 8.

STEP 2. Check of the heater element of the door mirror (RH)
Check the heater element of the door mirror (RH). (Refer to Heater Element Check .)

Q. Is the check result normal?
Go to Step 3.
Replace the mirror glass of the door mirror assembly (RH).

STEP 3. Measure the resistance at the door mirror assembly (RH) connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Resistance between door mirror assembly (RH) connector (earth terminal) and body earth
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 5.
Go to Step 4.

STEP 4. Check of open circuit in earth line between the door mirror assembly (RH) connector and body earth.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Repair the connector(s) or wiring harness.

STEP 5. Measure the voltage at the door mirror assembly (RH) connector.
(1)Turn the ignition switch to the ON position.
(2)Turn on the rear window defogger switch.
(3)Disconnect the connector, and measure at the wiring harness side.
(4)Measure the voltage between door mirror assembly (RH) connector (power supply terminal) and body earth.
OK: System voltage

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Go to Step 6.

STEP 6. Check of open circuit in DEFO-1&DEFO-2 line between door mirror assembly (RH) connector and ETACS-ECU connector.

Q. Is the check result normal?
Go to Step 7.
Repair the connector(s) or wiring harness.

STEP 7. Retest the system.
Check that the heater element of the door mirror (RH) functions normally.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the door mirror assembly (RH).

STEP 8. Check of the heater element of the door mirror (LH)
Check the heater element of the door mirror (LH). (Refer to Heater Element Check .)

Q. Is the check result normal?
Go to Step 9.
Replace the mirror glass of the door mirror assembly (LH).

STEP 9. Measure the resistance at the door mirror assembly (LH) connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between door mirror assembly (LH) connector (earth terminal) and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 11.
Go to Step 10.

STEP 10. Check of open circuit in earth line between the door mirror assembly (LH) connector and body earth.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Repair the connector(s) or wiring harness.

STEP 11. Measure the voltage at the door mirror assembly (LH) connector.
(1)Turn the ignition switch to the ON position.
(2)Turn on the rear window defogger switch.
(3)Disconnect the connector, and measure at the wiring harness side.
(4)Voltage between door mirror assembly (LH) connector (power supply terminal) and body earth.
OK: System voltage

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Go to Step 12.

STEP 12. Check of open circuit DEFO-1&DEFO-2 line between door mirror assembly (LH) connector and ETACS-ECU connector.

Q. Is the check result normal?
Go to Step 13.
Repair the connector(s) or wiring harness.

STEP 13. Retest the system.
Check that the heater element works normally.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the door mirror assembly (LH).