Blower Motor Circuit [10/2018 - ]: Procedure

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PERFORM ACTIVE TEST USING TECHSTREAM

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
Enter the following menus: Body Electrical / Air Conditioner / Active Test.

Perform the Active Test according to the display on the Techstream.

Body Electrical > Air Conditioner > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Blower Motor	Blower motor with fan sub-assembly	Min.: 0 Max.: 31	-

Body Electrical > Air Conditioner > Active Test

Tester Display
Blower Motor

Result

Result	Proceed to
Blower motor with fan sub-assembly does not operate	A
Blower motor with fan sub-assembly operates but does not change speed	B

Result:

See step 5

Result:

See step 2

CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN SUB-ASSEMBLY - POWER SOURCE AND BODY GROUND)

Disconnect the blower motor with fan sub-assembly connector.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Front view of wire harness connector (to Blower Motor with Fan Sub-assembly)

Measure the voltage and resistance according to the value(s) in the table below.

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
A52-3 (+B) - Body ground	Power switch off	11 to 14 V

Standard Resistance

Tester Connection	Condition	Specified Condition
A52-1 (GND) - Body ground	Always	Below 1 Ω

Result

Proceed to
OK
NG

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result:

See step 3

CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)

Disconnect the F51 air conditioning amplifier assembly connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
A52-2 (SI) - F51-6 (BLW)	Always	Below 1 Ω
A52-2 (SI) or F51-6 (BLW) - Other terminals and body ground	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result:

See step 4

INSPECT BLOWER MOTOR WITH FAN SUB-ASSEMBLY

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Front view of wire harness connector (to Air Conditioning Amplifier Assembly)

Connect the A52 blower motor with fan sub-assembly connector.

Measure the voltage according to the value(s) in the table below.

Standard Voltage

Tester Connection	Condition	Specified Condition
F51-6 (BLW) - Body ground	Always	4.75 to 5.25 V

Result

Proceed to
OK
NG

Result:

REPLACE BLOWER MOTOR WITH FAN SUB-ASSEMBLY. Refer to REMOVAL [10/2018 - ]

Result:

See step 5

INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

*a	Component with harness connected (Air Conditioning Amplifier Assembly)

Connect the air conditioning amplifier assembly connector.
Turn the power switch on (IG).
Set the blower speed to LO.

Using an oscilloscope, check the waveform.

Item	Content
Terminal No.	F51-6 (BLW) - F51-4 (GND)
Tool Setting	2 V/DIV., 1 ms./DIV.
Condition	Power switch on (IG) Blower switch: LO

Waveform is similar to that shown in the illustration.

HINT:

The waveform varies with the blower speed.

Result

Proceed to
OK
NG

Result:

REPLACE BLOWER MOTOR WITH FAN SUB-ASSEMBLY. Refer to REMOVAL [10/2018 - ]

Result:

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]