Diagnosis Procedure

BLOWER MOTOR


Description


COMPONENT DESCRIPTION

Brush-less Motor
The blower motor utilizes a brush-less motor with a rotating magnet.





Quietness is improved over previous motors where the brush was the point of contact and the coil rotated.






Blower motor circuit









BLOWER MOTOR


Diagnosis Procedure

1.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis function STEP-4. Refer to Diagnosis Description (WITHOUT ACCS) or Diagnosis Description (WITH ACCS).





Does blower motor speed change according to each code No.?
YES - INSPECTION END
NO - GO TO 2.
2.CHECK POWER SUPPLY FOR BLOWER MOTOR
1. Disconnect blower motor connector.
2. Turn ignition switch ON.
3. Check voltage between blower motor harness connector and ground.





Is the inspection result normal?
YES - GO TO 3.
NO - GO TO 6.
3.CHECK BLOWER MOTOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between blower motor harness connector and ground.





Is the inspection result normal?
YES - GO TO 4.
NO - Repair harness or connector.
4.CHECK CIRCUIT CONTINUITY BETWEEN BLOWER MOTOR AND UNIFIED METER AND A/C AMP.
1. Disconnect unified meter and A/C amp. connector.
2. Check continuity between blower motor harness connector and unified meter and A/C amp. harness connector.





3. Check continuity between blower motor harness connector and ground.





Is the inspection result normal?
YES - GO TO 5.
NO - Repair harness or connector.
5.CHECK UNIFIED METER AND A/C AMP. OUTPUT SIGNAL
1. Reconnect blower motor connector and unified meter and A/C amp. connector.
2. Turn ignition switch ON.
3. Set MODE switch to VENT position.
4. Change fan speed from Lo to Hi, and check duty ratios between blower motor harness connector and ground by using an oscilloscope. Normal terminal 2 drive signal duty ratios are shown in the table below.





Is the inspection result normal?
YES - Replace blower motor after confirming the fan air flow does not change.
NO - Replace unified meter and A/C amp.
6.CHECK POWER VOLTAGE OF BLOWER RELAY
1. Turn ignition switch OFF.
2. Remove blower relay. Refer to Fuse Block - Junction Box (J/B).
3. Turn ignition switch ON.
4. Check the voltage between blower relay fuse block terminals and ground. Refer to Description and Operation for relay terminal assignment.





Is the inspection result normal?
YES - GO TO 7.
NO - Check ignition power supply circuit. Refer to Ignition Power Supply.
7.CHECK BLOWER RELAY
1. Turn ignition switch OFF.
2. Install blower relay. Refer to Fuse Block - Junction Box (J/B).
3. Check operation sound of the blower relay after switching ignition switch ON.
Is the inspection result normal?
YES - GO TO 8.
NO - Replace blower relay.
8.CHECK FUSE
Check fuse 15A [Nos. 21 and 22, located in the fuse block (J/B)]. Refer to Fuse Block - Junction Box (J/B).
Is the inspection result normal?
YES - Repair harness or connector.
NO - Be sure to eliminate cause of malfunction before installing new fuse.