[55B] AUTOMATIC AIR CONDITIONER - - TROUBLESHOOTING - SYMPTOM PROCEDURES - INSPECTION PROCEDURE 4: The blower does not work.PRINT PAGE / INDEX / PRIOR / NEXT
INSPECTION PROCEDURE 4: The blower does not work.
COMMENTS ON TROUBLE SYMPTOM
If the blower motor does not operate, the blower motor circuit system may be defective.
POSSIBLE CAUSES
  • Malfunction of the blower motor (blower linear controller).
  • Malfunction of the automatic air conditioner control panel (A/C-ECU)
  • Damaged the wiring harness or connectors
DIAGNOSIS
Step 1. MUT-II/III actuator test
Carry out the actuator test.
  • Item 01, 02, 03, 04: Blower motor
Q: Does the blower motor work normally?
YES:  Replace the automatic air conditioner control panel (A/C-ECU)
NO:  Go to Step 2.
Step 2. Measure the voltage at the C-32 blower motor connector.
  1. Disconnect the connector, and measure at the wiring harness side.
  1. Turn the ignition switch to the ON position.
  1. Voltage between terminal 6 and body earth
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 15.
NO:  Go to Step 3.
Step 3. Check the blower relay.
Refer to GROUP 55A - On-vehicle Service .
Q: Is the blower relay in good condition?
YES:  Go to Step 4.
NO:  Replace the blower relay.
Step 4. Measure the voltage at C-207 blower relay connector.
  1. Remove the relay, and measure at the junction block side.
  1. Turn the ignition switch to the ON position.
  1. Voltage between terminal 1 and body 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: C-207 blower relay connector
Q: Is the check result normal?
YES:  Go to Step 6.
NO:  Repair the connector.
Step 6. Check the wiring harness between C-207 blower relay connector terminal No.1 and the ignition switch (IG2).
NOTE: Prior to the wiring harness inspection, check junction block connector C-203, and repair if necessary.
  • Check the power supply line for open circuit.
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 C-207 blower relay connector.
  1. Remove the relay, and measure at the junction block side.
  1. Voltage between terminal 5 and body 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: C-207 blower relay connector
Q: Is the check result normal?
YES:  Go to Step 9.
NO:  Repair the connector.
Step 9. Check the wiring harness between C-307 blower relay connector terminal No.5 and 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.
  • Check the power supply line for open circuit.
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. Measure the resistance at C-207 blower relay connector.
  1. Remove the relay, and measure at the junction block side.
  1. Continuity between terminal 3 and body earth.
    2. OK: 2Ω or less
Q: Is the check result normal?
YES:  Go to Step 13.
NO:  Go to Step 11.
Step 11. Connector check: C-207 blower relay connector
Q: Is the check result normal?
YES:  Go to Step 12.
NO:  Repair the connector.
Step 12. Check the wiring harness between C-207 blower relay connector terminal No.3 and body earth.
NOTE: Prior to the wiring harness inspection, check junction block connector C-205, and repair if necessary.
  • Check the earth wires for open circuit.
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 13. Connector check: C-207 blower relay connector and C-32 blower linear controller connector
Q: Is the check result normal?
YES:  Go to Step 14.
NO:  Repair the connector.
Step 14. Check the wiring harness between C-207 blower relay connector terminal No.4 and C-32 blower linear controller connector terminal No.6.
NOTE: Prior to the wiring harness inspection, check junction block connector C-203, and repair if necessary.
  • Check the power supply line for open circuit.
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 15. Measure the resistance at the C-32 blower linear controller connector.
  1. Disconnect the connector, and measure at the wiring harness side.
  1. Continuity between terminal 3 and body earth.
    2. OK: 2Ω or less
Q: Is the check result normal?
YES:  Go to Step 18.
NO:  Go to Step 16.
Step 16. Connector check: C-32 blower liner controller
Q: Is the check result normal?
YES:  Go to Step 17.
NO:  Repair the connector.
Step 17. Check the wiring harness between C-32 blower motor connector terminal No.3 and body earth.
  • Check the earth wires for open circuit.
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 18. Connector check: C-27 A/C-ECU connector and C-32 blower linear controller connector
Q: Is the check result normal?
YES:  Go to Step 19.
NO:  Repair the connector.
Step 19. Check the wiring harness between C-27 A/C-ECU connector terminal No.2 and C-32 blower motor connector terminal No.5.
  • Check the input line for open or short circuit.
Q: Is the check result normal?
YES:  Replace the air conditioner control panel (A/C-ECU) or the blower motor (blower linear controller).
NO:  Repair the wiring harness.
[55B] AUTOMATIC AIR CONDITIONER - - TROUBLESHOOTING - SYMPTOM PROCEDURES - INSPECTION PROCEDURE 4: The blower does not work.PRINT PAGE / INDEX / PRIOR / NEXT
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