Toyota Sienna Service Manual: Compressor Lock Sensor Circuit

DTC B1422/22 Compressor Lock Sensor Circuit

SYSTEM DESCRIPTION

The ECM sends an engine speed signal to the A/C amplifier via CAN communication and BEAN communication.

The A/C amplifier reads the difference between compressor speed and engine speed. When the difference becomes too large, the A/C amplifier determines that the compressor locks, and turns the magnetic clutch off.

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK CAN COMMUNICATION SYSTEM

(a) Use the intelligent tester to check if the CAN communication system is functioning normally.

Result

2 CHECK MULTIPLEX COMMUNICATION SYSTEM

(a) Use the intelligent tester to check if the multiplex communication system (BEAN) is functioning normally.

Result

3 INSPECT A/C AMPLIFIER

(a) Remove the A/C amplifier with the connectors still connected.

(b) Measure the waveform of the connector.

Standard

Result

4 INSPECT COMPRESSOR AND MAGNETIC CLUTCH (A/C LOCK SENSOR)

(a) Disconnect the connector from the A/C compressor.

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

Standard resistance

5 CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - A/C LOCK SENSOR)

(a) Disconnect the connector from the A/C amplifier.

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

Standard resistance

REPLACE A/C AMPLIFIER