Blower Motor Circuit

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: Blower Motor Circuit
- Blower Motor Circuit

DESCRIPTION

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

WIRING DIAGRAM

1. w/o Solar Ventilation System





2. w/ Solar Ventilation System





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 power switch on (IG).

(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:

Blower motor operates and blower motor speed level changes.

Result:





B -- CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - BODY GROUND)

C -- INSPECT SOLAR VENTILATION RELAY

D -- INSPECT A/C AMPLIFIER

E -- CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - A/C AMPLIFIER, SOLAR VENTILATION ECU)

A -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Air Conditioning System

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

(a) Disconnect the blower motor 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.

3. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - 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.

4. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - A/C AMPLIFIER)

(a) Disconnect the A/C amplifier 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.

5. INSPECT BLOWER MOTOR

(a) Reconnect the blower motor connector.

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





Standard Voltage:





Text in Illustration





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

6. INSPECT A/C AMPLIFIER

(a) Remove the A/C amplifier.





(b) Reconnect the A/C amplifier connector.

(c) Turn the power switch on (IG).

(d) Set the blower speed to LO.

(e) Measure the waveform between terminal L17-23 (BLW) of the A/C amplifier and body ground.





OK:

Waveform is as shown in the illustration.

HINT
The waveform varies with the blower speed.

Text in Illustration





NG -- REPLACE A/C AMPLIFIER Removal

OK -- REPLACE BLOWER MOTOR Removal

7. INSPECT SOLAR VENTILATION RELAY

(a) Remove the solar ventilation relay from the relay block No. 2-1.





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

Standard Resistance:





NG -- REPLACE SOLAR VENTILATION RELAY
OK -- Continue to next step.

8. CHECK HARNESS AND CONNECTOR (SOLAR VENTILATION RELAY - BATTERY)

(a) Disconnect the solar ventilation relay connector.





(b) 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.

9. CHECK HARNESS AND CONNECTOR (SOLAR VENTILATION RELAY - 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.

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

(a) Disconnect the blower motor 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.

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

(a) Reinstall the solar ventilation relay.

(b) Reconnect the solar ventilation relay connector.

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





Standard Voltage:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (BLOWER MOTOR - RELAY BLOCK NO. 2-1)
OK -- Continue to next step.

12. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - A/C AMPLIFIER, SOLAR VENTILATION ECU)

(a) Disconnect the A/C amplifier connector.





(b) Disconnect the solar ventilation ECU connector.





(c) 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.

13. INSPECT BLOWER MOTOR

(a) Reconnect the blower motor connector.

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





Standard Voltage:





Text in Illustration





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

14. INSPECT A/C AMPLIFIER

(a) Remove the A/C amplifier.





(b) Reconnect the A/C amplifier connector.

(c) Turn the power switch on (IG).

(d) Set the blower speed to LO.

(e) Measure the waveform between terminal L17-23 (BLW) of the A/C amplifier and body ground.





OK:

Waveform is as shown in the illustration.

HINT
The waveform varies with the blower speed.

Text in Illustration





NG -- REPLACE A/C AMPLIFIER Removal

OK -- REPLACE BLOWER MOTOR Removal