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:
Cooling system
On-vehicle inspection
1. INSPECT FOR COOLANT LEAK
CAUTION:
Do not remove the radiator cap while the engine and
radiator are still hot. Pressurized, hot engine coolant
and steam may be released and cause serious
burns.
NOTICE:
Before performing each inspection, turn the A/ ...
Customer problem analysis
HINT:
In troubleshooting, confirm that the problem symptoms
have been accurately identified. Preconceptions should be
discarded in order to make an accurate judgment. To
clearly understand what the problem symptoms are, it is
extremely important to ask the customer about the
problem an ...
Readiness monitor drive
pattern
1. PURPOSE OF READINESS TESTS
The On-Board Diagnostic (OBD II) system is
designed to monitor the performance of emissionrelated
components, and indicate any detected
abnormalities with DTCs (Diagnostic Trouble Codes).
Since various components need to be monitored in
different d ...