Blower Motor Circuit: Procedure
- PERFORM ACTIVE TEST USING TECHSTREAM (BLOWER MOTOR)
- Connect the Techstream to the DLC3.
- Turn the ignition switch to ON and turn the Techstream main switch on.
- Select the item below in the Active Test, and then check that the blower with fan motor sub-assembly operates.ACTIVE TEST / AIR CONDITIONER
Tester Display Test Part Control Range Diagnostic Note Blower Motor Blower with fan motor sub-assembly Min.: 0, Max.: 31 - RESULTResult Proceed to NG (blower with fan motor sub-assembly does not operate) A NG (blower with fan motor sub-assembly operates but does not change speed) B OK C
B → See step 5
C → See step 8
A: Go to next step
- INSPECT FUSE (HTR)
- Remove the HTR H-fuse from the engine room relay block.
- Measure the resistance of the HTR H-fuse.
Standard resistance
Tester Connection Condition Specified Condition HTR H-fuse Always Below 1 Ω
NG → REPLACE FUSE
OK: Go to next step
- CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - BODY GROUND)
- Disconnect the D34 motor connector.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
Tester Connection Condition Specified Condition D34-1 (GND) - Body ground Always Below 1 Ω
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
- CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - BATTERY)
- Install the HTR H-fuse.
- Measure the voltage according to the value(s) in the table below.
Standard voltage
Tester Connection Condition Specified Condition D34-3 (+B) - Body ground Always 11 to 14 V
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
- CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BLOWER MOTOR AND BODY GROUND)
- Disconnect the D37 amplifier connector.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
Tester Connection Condition Specified Condition D37-23 (BLW) - D34 - 2 (SI) Always Below 1 Ω D37-14 (GND) - Body ground Always Below 1 Ω
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
- CHECK AIR CONDITIONING AMPLIFIER
- Reconnect the D37 amplifier connector.
- Remove the air conditioning amplifier with its connectors still connected. Refer to REMOVAL .
- Check the waveform at the amplifier connector.
OK
Waveform is as shown in the illustration.
HINT:
The waveform varies with the blower level.
Item Content Tester Connection D37-23 (BLW) - D37-14 (GND) Tool Setting 1 V/DIV., 500 μsec./DIV. Condition Ignition switch ON
Blower switch LO
NG → See step 9
OK → See step 7
- REPLACE BLOWER WITH FAN MOTOR SUB-ASSEMBLY. Refer to DISASSEMBLY
- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE
- REPLACE AIR CONDITIONING AMPLIFIER. Refer to REMOVAL