Rear Blower Motor Circuit

HEATING / AIR CONDITIONING: 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.

HINT
The rear blower motor operates when the rear cooler switch is on and the front blower switch is in the FACE or B/L position.

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT
Before starting the following inspection, check the fuses and relays related to this circuit.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - REAR COOLER SWITCH)

(a) Disconnect the F47, F48 and F64 connectors.

(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.

2. INSPECT REAR COOLER SWITCH (REAR CONSOLE BOX)

(a) Remove the rear cooler switch (rear console box).

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

Standard Resistance:

NG -- REPLACE REAR COOLER SWITCH (REAR CONSOLE BOX) Removal
OK -- Continue to next step.

3. INSPECT AIR CONDITIONING AMPLIFIER

(a) Reconnect the F47 and F48 connectors.

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

Standard Voltage:

NG -- REPLACE AIR CONDITIONING AMPLIFIER Removal
OK -- Continue to next step.

4. INSPECT COOLER BLOWER ASSEMBLY

(a) Reconnect the cooler blower assembly connector.

(b) Check the cooler blower assembly operation.

OK:

NG -- REPLACE COOLER BLOWER ASSEMBLY
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (COOLER BLOWER ASSEMBLY CIRCUIT)

(a) Disconnect the F62 rear motor control connector.

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

Standard Resistance:

NG -- REPLACE REAR COOLER SWITCH (REAR CONSOLE BOX) Removal
OK -- Continue to next step.

6. INSPECT COOLER BLOWER ASSEMBLY

(a) Disconnect the F62 connector.

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

Standard Voltage:

NG -- REPLACE COOLER BLOWER ASSEMBLY
OK -- Continue to next step.

7. CHECK HARNESS AND CONNECTOR (REAR BLOWER MOTOR CONTROL - A/C AMPLIFIER ASSEMBLY)

(a) Disconnect the F48 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 BLOWER MOTOR CONTROL

(a) Reconnect the F62 connector.

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

Standard Voltage:

NG -- CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER CIRCUIT)
OK -- Continue to next step.

9. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

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

(b) Check the waveform.

OK:

Waveform is as shown in the illustration.

HINT
The waveform varies with the blower level.

Text in Illustration

NG -- REPLACE AIR CONDITIONING AMPLIFIER Removal

OK -- REPLACE BLOWER MOTOR CONTROL Blower Motor

10. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER CIRCUIT)

(a) Disconnect the F47 and F48 connectors.

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

Standard Voltage:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE BLOWER MOTOR CONTROL Blower Motor