AIR CONDITIONING SYSTEM Blower Motor Circuit

DESCRIPTION

The blower motor with fan sub-assembly is operated by signals from the air conditioning amplifier assembly. Blower motor speed signals are transmitted in accordance with changes in the duty ratio.

WIRING DIAGRAM

*a	from Auxiliary Battery
*b	Front Blower Motor with Fan Sub-assembly
*c	Air Conditioning Amplifier Assembly

CAUTION / NOTICE / HINT

PROCEDURE

1. PERFORM ACTIVE TEST USING GTS

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the power switch on (IG).

   3. Turn the GTS on.

   4. Enter the following menus: Body Electrical / Air Conditioner / Active Test.

   5. Check the operation by referring to the table below.

      Air Conditioner

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

      OK
      Blower motor with fan sub-assembly operates and blower motor speed level changes.

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

   
   

   A

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

   C

   INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

   B

2. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN - BODY GROUND)

   
   

   1. Disconnect the L33 blower motor with fan sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition L33-1 (GND) - Body ground Always Below 1 Ω

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

3. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN - POWER SOURCE)

   
   
   1. 

      Text in Illustration

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

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

      Standard Voltage
      Tester Connection Condition Specified Condition L33-3 (+B) - Body ground Power switch off 11 to 14 V

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN - AIR CONDITIONING AMPLIFIER)

   
   

   1. Disconnect the L17 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition L17-23 (BLW) - L33-2 (SI) Always Below 1 Ω L17-23 (BLW) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

5. INSPECT BLOWER MOTOR WITH FAN SUB-ASSEMBLY

   
   

   1. Reconnect the L33 blower motor with fan sub-assembly connector.

   2. 

      Text in Illustration

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

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

      Standard Voltage
      Tester Connection Condition Specified Condition L17-23 (BLW) - Body ground Power switch off 4.5 to 5.5 V

   
   

   NG

   REPLACE BLOWER MOTOR WITH FAN SUB-ASSEMBLY Click here

   OK

6. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

   
   
   1. 

      Text in Illustration

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

      Remove the air conditioning amplifier assembly Click here.

   2. Reconnect the L17 air conditioning amplifier assembly connector.

   3. Turn the power switch on (IG).

   4. Set the blower speed to low.

   5. Measure the waveform between terminal L17-23 (BLW) of the air conditioning amplifier assembly and body ground.

      Item	Content
      Tool setting	1 V/DIV., 500 μs/DIV.
      Vehicle condition	Power switch on (IG) Blower set to low

      OK
      Waveform is as shown in the illustration.

      Tech Tips

      The waveform varies with the blower speed.

   
   

   OK

   REPLACE BLOWER MOTOR WITH FAN SUB-ASSEMBLY Click here

   NG

   REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here