Blower Motor Circuit

AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System): Blower Motor Circuit
- Blower Motor Circuit

DESCRIPTION

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

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM (BLOWER MOTOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG) and turn the Techstream main switch on.

(c) Select the item below in the Active Test, and then check that the blower motor operates.

Active Test / Air Conditioner





Result:





C -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Air Conditioning System (For Automatic Air Conditioning System)

B -- CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BODY GROUND)
A -- Continue to next step.

2. INSPECT FUSE (HTR)

(a) Remove the HTR-H fuse from the main body ECU.

(b) Measure the resistance of the HTR-H fuse.

Standard resistance:





NG -- REPLACE FUSE
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - BODY GROUND)

(a) Disconnect the D34 motor connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - BATTERY)

(a) Disconnect the D34 motor connector.





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

Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BODY GROUND)

(a) Disconnect the D37 amplifier connector.





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

Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

6. CHECK AIR CONDITIONING AMPLIFIER

(a) Remove the air conditioning amplifier with its connectors still connected.





(b) Check the waveform at the amplifier connector.

OK:

Waveform is as shown in the illustration.

HINT
The waveform varies with the blower level.





NG -- REPLACE AIR CONDITIONING AMPLIFIER

OK -- REPLACE BLOWER W/ FAN MOTOR SUB-ASSEMBLY