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INSPECTION PROCEDURE 4: Blower Fan and Motor do not Turn.
 
 
 
 
 
 
CIRCUIT OPERATION
If the blower motor does not operate, the blower relay system is suspected.
 
 
 
TROUBLESHOOTING HINTS
  • Malfunction of the power transistor
  • Malfunction of the blower motor
  • Malfunction of the A/C control panel
  • Damaged wiring harness or connectors
 
 
 
DIAGNOSIS
Required Special Tools:
  • MB991223: Harness Set
  • MB992006: Extra Fine Probe
STEP 1. Check blower motor connector C-213 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Is blower motor connector C-213 in good condition?
Go to Step 2.
Repair or replace the connector. Refer to GROUP 00E, Harness Connector Inspection .The blower motor should operate normally.
 
STEP 2. Measure the voltage at blower motor connector C-213.
(1) Disconnect blower motor connector C-213, and measure the voltage at the wiring harness side.
(2) Turn the ignition switch to the "ON" position.
(3) Turn the blower switch to the "Maximum air volume" position.
(4) Measure the voltage between terminal 1 and ground.
  • The measured value should be approximately 12 volts (battery positive voltage).
Is the measured voltage approximately 12 volts?
Go to Step 3.
Refer to Inspection procedure 10, "Blower motor power supply system ."
 
STEP 3. Check blower motor connector C-213 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Is blower motor connector C-213 in good condition?
Go to Step 4.
Repair or replace the connector. Refer to GROUP 00E, Harness Connector Inspection .The blower motor should operate normally.
 
STEP 4. Check the blower fan and motor operation.
Check that the motor turns when applying battery power between the connector terminals. Also check to see that there is no abnormal sound emitted from the motor at this time.
Is there any abnormal noise?
Go to Step 5.
Replace the blower relay. The blower motor should operate normally.
 
STEP 5. Check A/C control panel connector C-216 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Is A/C control panel connector C-216 in good condition?
Go to Step 6.
Repair or replace the connector. Refer to GROUP 00E, Harness Connector Inspection .The blower motor should operate normally.
 
STEP 6. Check the wiring harness between A/C control panel connector C-216 (terminal 16) and blower motor connector C-213 (terminal 2).
  • Check the A/C control panel signal line for open and short circuit.
Is the wiring harness between A/C control panel connector C-216 (terminal 16) and blower motor connector C-213 (terminal 2) in good condition?
Go to Step 7.
Repair the wiring harness. The blower motor should operate normally.
 
STEP 7. Check power transistor connector C-219 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Is power transistor connector C-219 in good condition?
Go to Step 8.
Repair or replace the connector. Refer to GROUP 00E, Harness Connector Inspection .The blower motor should operate normally.
 
STEP 8. Measure the resistance at power transistor connector C-219.
(1) Disconnect power transistor connector C-219, and measure the resistance at the wiring harness side.
(2) Measure the resistance value between terminal 1 and ground.
OK: The measured value should be 2 ohms or less
Does the measured resistance value correspond with this range?
Go to Step 11.
Go to Step 9.
 
STEP 9. Check grounding connector C-01 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Is grounding connector C-01 in good condition?
Go to Step 10.
Repair or replace the connector. Refer to GROUP 00E, Harness Connector Inspection .
 
STEP 10. Check the wiring harness between power transistor connector C-219 (terminal 1) and grounding connector C-01 (terminal 6), between grounding connector C-01 (terminal 6) and A/C control panel connector C-216 (terminal 9).
  • Check the power transistor ground line for open circuit.
Is the wiring harness between power transistor connector C-219 (terminal 1) and grounding connector C-01 (terminal 6), between grounding connector C-01 (terminal 6) and A/C control panel connector C-216 (terminal 9) good condition?
It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions .
Repair the wiring harness. The blower motor should operate normally.
 
STEP 11. Check the wiring harness between A/C control panel connector C-216 (terminals 16 and 15) and power transistor connector C-219 (terminals 2 and 4).
  • Check the A/C control panel signal line for open and short circuit.
Is the wiring harness between A/C control panel connector C-216 (terminals 16 and 15) and power transistor connector C-219 (terminals 2 and 4) in good condition?
Go to Step 12.
Repair the wiring harness. The blower motor should operate normally.
 
STEP 12. Replace the power transistor and check the trouble symptom again
Check the trouble symptom again.
Is the check result satisfactory?
The procedure is complete.
Replace the A/C control panel.