[55B] AUTOMATIC AIR CONDITIONER - - TROUBLESHOOTING - SYMPTOM PROCEDURES - INSPECTION PROCEDURE 9: Rear Window Defogger function does not operate.PRINT PAGE / INDEX / PRIOR / NEXT
INSPECTION PROCEDURE 9: Rear Window Defogger function does not operate.
CIRCUIT OPERATION
If the rear window defogger does not operate when the rear window defogger switch is turned on, the rear window defogger relay system may be defective.
TROUBLESHOOTING HINTS
  • Malfunction of the A/C-ECU
  • Malfunction of the rear window defogger relay
  • Damaged the wiring harness or connectors
  • Malfunction of the rear window defogger
DIAGNOSIS
Step 1. Check the A/C and outside/inside air selection damper control motor operation.
Q: Do the A/C and outside/inside air selection damper control motor work normally?
YES:  Go to Step 2.
NO:  Refer to Inspection procedure 10 "Malfunction of the A/C-ECU power supply system ."
Step 2. Measure the voltage at rear window defogger connector F-04.
  1. Disconnect rear window defogger connector F-04, and measure the voltage at the harness side.
  1. Disconnect C-27 A/C-ECU connector, and earth terminal 16.
  1. Measure the voltage between terminal 1 and earth.
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 14.
NO:  Go to Step 3.
Step 3. Check the rear window defogger relay continuity.
Refer to .
Q: Is the rear window defogger relay continuity in good condition?
YES:  Go to Step 4.
NO:  Replace the rear window defogger relay.
Step 4. Measure the voltage at rear window defogger relay connector C-206.
  1. Disconnect rear window defogger relay connector C-206, and measure the voltage at the junction block side.
  1. Measure the voltage between terminal 5 and earth.
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 7.
NO:  Go to Step 5.
Step 5. Connector check: rear window defogger relay connector C-206
Q: Is the check result normal?
YES:  Go to Step 6.
NO:  Repair or replace the connector.
Step 6. Check the wiring harness between rear window defogger relay connector C-206 (terminal 5) and the fusible link (1).
NOTE: Prior to the wiring harness inspection, check intermediate connectors C-125, A-14 and junction block connector C-204, and repair if necessary.
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the wiring harness.
Step 7. Measure the voltage at rear window defogger relay connector C-206.
  1. Disconnect rear window defogger relay connector C-206, and measure the voltage at the junction block side.
  1. Turn the ignition switch to the "ON" position.
  1. Measure the voltage between terminal 1 and earth.
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 10.
NO:  Go to Step 8.
Step 8. Connector check: rear window defogger relay connector C-206
Q: Is the check result normal?
YES:  Go to Step 9.
NO:  Repair or replace the connector.
Step 9. Check the wiring harness between rear window defogger relay connector C-206 (terminal 1) and ignition switch (IG2).
NOTE: Prior to the wiring harness inspection, check junction block connector C-203, and repair if necessary.
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the wiring harness.
Step 10. Connector check: rear window defogger relay connector C-206 and A/C-ECU connector C-27 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is the check result normal?
YES:  Go to Step 11.
NO:  Repair or replace the connector.
Step 11. Check the wiring harness between rear window defogger relay connector C-206 (terminal 3) and A/C-ECU connector C-27 (terminal 16).
NOTE: Prior to the wiring harness inspection, check junction block connector C-205, and repair if necessary.
Q: Is the check result normal?
YES:  Go to Step 12.
NO:  Repair the wiring harness.
Step 12. Check rear window defogger relay connector C-206 and rear window defogger connector F-04 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is the check result normal?
YES:  Go to Step 13.
NO:  Repair or replace the connector.
Step 13. Check the wiring harness between rear window defogger relay connector C-206 (terminal 4) and rear window defogger connector F-04 (terminal 1).
NOTE: Prior to the wiring harness inspection, check junction block connector C-221, and repair if necessary.
Q: Is the check result normal?
YES:  Replace the automatic air conditioner control panel (A/C-ECU).
NO:  Repair the wiring harness.
Step 14. Measure at rear window defogger connector F-01 to check the earth circuit to the rear window defogger connector.
  1. Disconnect rear window defogger connector F-01, and measure at the wiring harness side.
  1. Measure the resistance value between terminal 1 and earth.
    2. OK: 2 ohms or less
Q: Is the check result normal?
YES:  Go to Step 17.
NO:  Go to Step 15.
Step 15. Connector check: rear window defogger connector F-01
Q: Is the check result normal?
YES:  Go to Step 16.
NO:  Repair the connector.
Step 16. Check the wiring harness between rear window defogger connector F-01 (terminal 1) and earth.
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair or replace the wiring harness.
Step 17. Check the rear window defogger.
Refer to GROUP 54A, Defogger .
Q: Does the rear window defogger work normally?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the rear window defogger.
[55B] AUTOMATIC AIR CONDITIONER - - TROUBLESHOOTING - SYMPTOM PROCEDURES - INSPECTION PROCEDURE 9: Rear Window Defogger function does not operate.PRINT PAGE / INDEX / PRIOR / NEXT
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