Blower Motor Circuit: Procedure

1. Connect Techstream to the DLC3.
2. Turn the ignition switch on (IG) and turn Techstream main switch on.
3. Select the item below in the Active Test, and then check that the blower motor operates.
   ACTIVE TEST / AIR CONDITIONER
   
   

   Tester Display	Test Part	Control Range	Diagnostic Note
   Blower Motor	Blower motor	Min.: 0, Max.: 31	-

   Result

   Result	Proceed to
   NG (blower motor does not operate)	A
   NG (blower motor operates but does not change speed)	B
   OK	C

B → See step   5 

C → See step   8 

A: Go to next step 

1. Remove the HTR fuse from the main body ECU.
2. Measure the resistance of the HTR fuse.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   HTR fuse	Always	Below 1 Ω

NG → REPLACE FUSE 

OK: Go to next step 

1. Disconnect the D34 motor connector.
   Fig 1: Checking Harness And Connector (Blower Motor - Body Ground)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. 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 

1. Disconnect the D34 motor connector.
   Fig 2: Checking Harness And Connector (Blower Motor - Battery)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. 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 

1. Disconnect the D37 amplifier connector.
   Fig 3: Checking Harness And Connector (Air Conditioning Amplifier - Body Ground)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage according to the value(s) in the table below.

   Standard voltage

   Tester Connection	Condition	Specified Condition
   D37-23 (BLW) - D37-14 (GND)	Ignition switch on (IG) Blower switch OFF	4.5 to 5.5 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Remove the air conditioning amplifier with its connectors still connected.
   Fig 4: Checking Air Conditioning Amplifier

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the waveform of the amplifier connector.

   OK

   Waveform is as shown in the illustration.

   HINT: 

   The waveform varies with the blower level.

   Item	Content
   Tester Connection	BLW (D37-23) - GND (D37-14)
   Tool Setting	1 V/DIV., 500 μsec./DIV.
   Condition	Ignition switch on (IG) Blower switch LO

NG → See step   9 

OK → See step   7