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:
Coolant
Replacement
1. REMOVE NO. 1 ENGINE UNDER COVER (See page
EM-26)
2. REMOVE V-BANK COVER SUB-ASSEMBLY (See
page EM-28)
3. DRAIN ENGINE COOLANT
(a) Loosen the radiator drain cock plug.
HINT:
Collect the coolant in a container and dispose of it
according to the regulations in your area.
(b ...
Removal
1. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
2. REMOVE FRONT BUMPER ASSEMBLY
Remove the 4 screws and separate the fender liner
from the front bumper assembly.
Remove the 8 screws and separate the engine
under cover from the front bumper assembly.
Remove the 5 ...
Engine Hood Courtesy Switch Circuit
DESCRIPTION
The engine hood courtesy switch is built in the engine hood lock assembly.
The switch turns on when the
engine hood is opened and turns off when the engine hood is closed.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT ENGINE HOOD COURTESY SWITCH
Remove the courtesy swi ...
