Rear Blower Motor Circuit

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

DESCRIPTION

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

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Air Conditioner / Active Test.

(e) Check the operation by referring to the table below.

Air Conditioner





OK:

Rear blower motor operates and rear blower motor speed level changes.

Result





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

B -- INSPECT AIR CONDITIONING AMPLIFIER
A -- Continue to next step.

2. INSPECT REAR BLOWER MOTOR

(a) Disconnect the rear blower motor connector.





(b) Connect a battery positive (+) lead to terminal 2 and a negative (-) lead to terminal 1, then check that the rear blower motor operates smoothly.

OK:

The rear blower motor operates smoothly.

Text in Illustration





NG -- REPLACE REAR BLOWER MOTOR Removal
OK -- Continue to next step.

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

(a) Disconnect the rear blower controller connector.





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

Standard Resistance:





Text in Illustration





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

4. CHECK HARNESS AND CONNECTOR (REAR BLOWER CONTROLLER - BATTERY)

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





Standard Voltage:





Text in Illustration





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

5. CHECK HARNESS AND CONNECTOR (REAR BLOWER CONTROLLER - REAR BLOWER MOTOR)

(a) 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.

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

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





Standard Resistance:





Text in Illustration





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

7. CHECK HARNESS AND CONNECTOR (REAR BLOWER CONTROLLER - A/C AMPLIFIER)

(a) Disconnect the air conditioning amplifier 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.

8. INSPECT REAR BLOWER CONTROLLER

(a) Reconnect the rear blower controller connector.





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

Standard Voltage:





Text in Illustration





NG -- REPLACE REAR BLOWER CONTROLLER Removal
OK -- Continue to next step.

9. INSPECT AIR CONDITIONING AMPLIFIER

(a) Reconnect the air conditioning amplifier connector.

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





(c) Measure the waveform between terminal D74-22 (BLWH) of the air conditioning amplifier and body ground.





Text in Illustration





OK:

Waveform is as shown in the illustration.

HINT
The waveform varies with the blower level.

NG -- REPLACE AIR CONDITIONING AMPLIFIER Removal

OK -- REPLACE REAR BLOWER CONTROLLER Removal