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
Solar Sensor Circuit (Passenger Side)
DTC B1421/21 Solar Sensor Circuit (Passenger Side)
DESCRIPTION
The solar sensor, which is installed on the upper side of the instrument
panel, detects sunlight and
controls the air conditioni ...
Pressure Sensor Circuit
DTC B1423/23 Pressure Sensor Circuit
DESCRIPTION
This DTC is output when refrigerant pressure on the high pressure side is
extremely low (0.19 MPa (2.0
kgf/cm2, 28 psi) or less) or extremely high ...
Other materials:
The Rear Cross Traffic Alert function
The Rear Cross Traffic Alert functions when your vehicle is in reverse.
It can detect other vehicles approaching from the right or left rear of
the vehicle. It uses radar sensors to alert the driver of the other vehicle’s
existence through flashing the outside rear view mirror indicators
and ...
Reassembly
1. INSTALL NO. 1 COOLER THERMISTOR
(a) Install the No. 1 cooler thermistor as shown in the
illustration.
NOTICE:
Be sure to insert the thermistor only once
because reinserting it will not allow it to be
firmly secured.
When reusing the evaporator, insert the
thermistor one row ne ...
System description
1. DESCRIPTION OF OCCUPANT CLASSIFICATION SYSTEM
GENERAL DESCRIPTION.
In the occupant classification system, the
occupant classification ECU calculates the
weight of the occupant based on a signal from
the occupant classification sensors. This system
recognizes the occu ...
