Automatic Air Conditioning

AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System): B1479/79: Flow Sensor Circuit
B1479/79 - Flow Sensor Circuit

DESCRIPTION

The flow sensor is built into the compressor, and outputs a signal indicating the flow rate of the refrigerant. The air conditioning amplifier converts the received signal to refrigerant flow rate data according to the characteristics of the sensor, which it then sends to the ECM via CAN communication.





*1: As the flow sensor measures the flow rate of the refrigerant in the air conditioning system, it is necessary to turn the ignition switch to ON in order to check the state of the flow sensor.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM (FLOW SENSOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON and turn the Techstream on.

(c) Check the flow sensor voltage in the Data List.

Air Conditioner:





Result





B -- READ VALUE USING TECHSTREAM (FLOW SENSOR)
A -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (FLOW SENSOR - AIR CONDITIONING AMPLIFIER)

(a) Disconnect the B66 flow sensor connector.





(b) Disconnect the E37 amplifier connector.

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

Standard Resistance:





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

3. REPLACE FLOW SENSOR (COMPRESSOR AND PULLEY)

(a) Replace the flow sensor (compressor and pulley) with a normal one Removal.

NEXT -- Continue to next step.

4. CHECK FOR DTC

(a) Clear the DTCs DTC Check / Clear.

(b) Check for DTCs DTC Check / Clear.

OK:

DTC B1479 is not output.

NG -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Removal

OK -- END

5. READ VALUE USING TECHSTREAM (FLOW SENSOR)

(a) Check the flow sensor voltage in the Data List.

Air Conditioner:





Result





B -- CHECK FOR DTC
A -- Continue to next step.

6. REPLACE FLOW SENSOR (COMPRESSOR AND PULLEY)

(a) Replace the flow sensor (compressor and pulley) with a normal one Removal.

NEXT -- Continue to next step.

7. CHECK FOR DTC

(a) Clear the DTCs DTC Check / Clear.

(b) Check for DTCs DTC Check / Clear.

OK:

DTC B1479 is not output.

NG -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Removal

OK -- END