Compressor Lock Sensor Circuit - Air Conditioning System

AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1422/22: Compressor Lock Sensor Circuit
B1422/22 - Compressor Lock Sensor Circuit

DESCRIPTION

This sensor sends 1 pulse per engine revolution to the ECM.

If the ratio between engine and compressor speed deviates 20% or more compared to normal operation, the ECM turns the cooler compressor off and the indicator blinks at approximately 1 second intervals.

The ECM informs the A/C amplifier of the operation condition of the cooler compressor through multiplex communication (CAN and BEAN).





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK MULTIPLEX COMMUNICATION SYSTEM

(a) Use the Techstream to check if the Multiplex Communication System (MPX) is functioning normally.

Result:





B -- GO TO MULTIPLEX COMMUNICATION SYSTEM
A -- Continue to next step.

2. CHECK CAN COMMUNICATION SYSTEM

(a) Use the Techstream to check if the CAN Communication System is functioning normally.

Result:





B -- GO TO CAN COMMUNICATION SYSTEM
A -- Continue to next step.

3. INSPECT ECM

(a) Remove the ECM with its connectors still connected.





(b) Measure the waveform of the connector.

Standard:









Result:





B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

C -- REPLACE ECM
A -- Continue to next step.

4. INSPECT A/C COMPRESSOR (LOCK SENSOR)

(a) Disconnect the A/C compressor connector.





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

Standard resistance:





NG -- REPLACE A/C COMPRESSOR (LOCK SENSOR)
OK -- Continue to next step.

5. CHECK WIRE HARNESS (ECM - A/C COMPRESSOR)

(a) Disconnect the A/C compressor connector.





(b) Disconnect the ECM connector.

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

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ECM