Land Cruiser URJ200 URJ202 GRJ200 VDJ200 - HEATING / AIR CONDITIONING

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

CHECK HARNESS AND CONNECTOR (GROUND CIRCUIT)

INSPECT AIR CONDITIONER PRESSURE SENSOR (SENSOR SIGNAL CIRCUIT)

INSPECT AIR CONDITIONER PRESSURE SENSOR (SENSOR SIGNAL CIRCUIT)

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - PRESSURE SENSOR)

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - PRESSURE SENSOR)

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - PRESSURE SENSOR)

INSPECT FOR AIR CONDITIONING SYSTEM LEAK

CHARGE REFRIGERANT

RECHECK DTC

CHECK AIR CONDITIONER PRESSURE SENSOR

REPAIR AIR CONDITIONING SYSTEM LEAK

INSPECT CONDENSER FAN

CHARGE REFRIGERANT

RECHECK DTC

REPLACE COOLER EXPANSION VALVE

CHARGE REFRIGERANT

RECHECK DTC

DTC B1423/23 Pressure Sensor Circuit

DESCRIPTION

This DTC is output when refrigerant pressure is extremely low (-0.4566 MPaG (-4.6 kgf/cm2, -66 psi) or less) or extremely high (3.2943 MPaG (33.6 kgf/cm2, 477 psi) or more). The air conditioner pressure sensor, which is installed on the pipe of the high pressure side to detect refrigerant pressure, outputs the refrigerant pressure signal to the air conditioning amplifier assembly. The air conditioning amplifier assembly converts the signal to pressure according to the sensor characteristics to control the compressor.


  • HINT:
  • Be sure to check the refrigerant volume first when this DTC is output because this DTC can also be output if there is no refrigerant in the cycle.
DTC CodeDTC Detection ConditionTrouble Area
B1423/23
An open or short in the air conditioner pressure sensor circuit
Refrigerant pressure on the high pressure side is extremely low (-0.4566 MPaG (-4.6 kgf/cm2, -66 psi) or less) or extremely high (3.2943 MPaG (33.6 kgf/cm2, 477 psi) or more)
Air conditioner pressure sensor
Harness or connector
Cooler expansion valve (blocked, stuck)
Cooler condenser assembly (blocked, deterioration of cooling capacity due to dirt)
Cooler dryer (moisture in the refrigerant cycle cannot be absorbed)
Condenser fan (condenser cannot be cooled down)
Air conditioning system (leaks, blocked)
Refrigerant pipe line
Air conditioning amplifier assembly

WIRING DIAGRAM

Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

INSPECTION PROCEDURE

1.CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)
Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Disconnect the A13 air conditioner pressure sensor connector.

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

  • Standard Voltage:
  • Tester ConnectionSwitch ConditionSpecified Condition
    A13-3 (+) - Body groundEngine switch on (IG)4.4 to 5.5 V
NG
Go to step 5
OK
2.CHECK HARNESS AND CONNECTOR (GROUND CIRCUIT)
Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

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

  • Standard Resistance:
  • Tester ConnectionConditionSpecified Condition
    A13-1 (-) - Body groundAlwaysBelow 1 Ω
NG
Go to step 6
OK
3.INSPECT AIR CONDITIONER PRESSURE SENSOR (SENSOR SIGNAL CIRCUIT)

Reconnect the A13 pressure sensor connector.

Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Remove the air conditioning amplifier with its connectors still connected.

  • Standard Voltage:
  • w/ Rear Heater:
  • Tester ConnectionSwitch ConditionSpecified Condition
    E35-20 (PRE) - Body ground
    Engine switch on (IG)
    A/C switch off
    		0.7 to 4.8 V
  • w/o Rear Heater:
  • Tester ConnectionSwitch ConditionSpecified Condition
    E81-9 (PRE) - Body ground
    Engine switch on (IG)
    A/C switch off
    		0.7 to 4.8 V
  • HINT:
  • If the measured voltage is not within the normal range, there may be a malfunction in the air conditioning amplifier assembly, air conditioner pressure sensor, or wire harness. It is also possible that the amount of refrigerant may not be appropriate.
NG
Go to step 7
OK
4.INSPECT AIR CONDITIONER PRESSURE SENSOR (SENSOR SIGNAL CIRCUIT)

Measure the voltage when the following conditions are satisfied.

ItemCondition
Engine Speed1500 rpm
Vehicle DoorsFully open
Temperature SettingMAX COLD
Blower SpeedHI
A/C SwitchON
R/F SwitchRECIRCULATION
Interior Temperature25 to 35°C (77 to 95°F)
  • NOTICE:
If refrigerant pressure on the high pressure side becomes extremely high during the inspection (if the voltage exceeds 4.8 V), the fail-safe function stops compressor operation. Therefore, measure the voltage before the fail-safe operation.
It is necessary to measure the voltage for a certain amount of time (approximately 10 minutes) because the problem symptom may recur after a while.
  • HINT:
  • When the outside air temperature is low (below -1.5°C (29.3°F)), the compressor stops due to operation of the ambient temperature and the evaporator temperature sensor to prevent the evaporator from freezing. In this case, perform the inspection in a warm indoor environment.
Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

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

  • Standard Voltage:
  • w/ Rear Heater:
  • Tester ConnectionSwitch ConditionSpecified Condition
    E35-20 (PRE) - Body ground
    Engine switch on (IG)
    A/C switch on
    		0.7 to 4.8 V
  • w/o Rear Heater:
  • Tester ConnectionSwitch ConditionSpecified Condition
    B81-9 (PRE) - Body ground
    Engine switch on (IG)
    A/C switch on
    		0.7 to 4.8 V
NG
Go to step 13
OK
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY ()
5.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - PRESSURE SENSOR)
Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Disconnect the E35*1 or E81*2 amplifier connector.

  • HINT:
  • *1: w/ Rear Heater
  • *2: w/o Rear Heater

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

  • Standard Resistance:
  • w/ Rear Heater:
  • Tester ConnectionConditionSpecified Condition
    A13-3 (+) - E35-27 (S5-1)AlwaysBelow 1 Ω
    E35-27 (S5-1) - Body groundAlways10 kΩ or higher
  • w/o Rear Heater:
  • Tester ConnectionConditionSpecified Condition
    A13-3 (+) - E81-30 (S5-1)AlwaysBelow 1 Ω
    E81-30 (S5-1) - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY ()
6.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - PRESSURE SENSOR)
Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Disconnect the E35*1 or E81*2 amplifier connector.

  • HINT:
  • *1: w/ Rear Heater
  • *2: w/o Rear Heater

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

  • Standard Resistance:
  • w/ Rear Heater:
  • Tester ConnectionConditionSpecified Condition
    A13-1 (-) - E35-16 (SG-2)AlwaysBelow 1 Ω
    E35-16 (SG-2) - Body groundAlways10 kΩ or higher
  • w/o Rear Heater:
  • Tester ConnectionConditionSpecified Condition
    A13-1 (-) - E81-13 (SG-2)AlwaysBelow 1 Ω
    E81-13 (SG-2) - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY ()
7.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - PRESSURE SENSOR)
Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Disconnect the E35*1 or E81*2 amplifier connector.

  • HINT:
  • *1: w/ Rear Heater
  • *2: w/o Rear Heater

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

  • Standard Resistance:
  • w/ Rear Heater:
  • Tester ConnectionConditionSpecified Condition
    A13-2 (PR) - E35-20 (PRE)AlwaysBelow 1 Ω
    E35-20 (PRE) - Body groundAlways10 kΩ or higher
  • w/o Rear Heater:
  • Tester ConnectionConditionSpecified Condition
    A13-2 (PR) - E81-9 (PRE)AlwaysBelow 1 Ω
    E81-9 (PRE) - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
8.INSPECT FOR AIR CONDITIONING SYSTEM LEAK

Install the manifold gauge set.

Recover the refrigerant from the air conditioning system using a refrigerant recovery unit.

Evacuate the air conditioning system and check that vacuum can be maintained in it.

  • OK:
  • Vacuum can be maintained in the air conditioning system.
  • HINT:
  • If vacuum cannot be maintained in the air conditioning system, refrigerant may be leaking from it. In this case, it is necessary to repair or replace the leaking part of the air conditioning system.
NG
Go to step 12
OK
9.CHARGE REFRIGERANT

Add an appropriate amount of refrigerant ().

NEXT
10.RECHECK DTC

Recheck for the DTC when the following conditions are satisfied.

ItemCondition
Engine Speed1500 rpm
Vehicle DoorsFully open
Temperature SettingMAX COLD
Blower SpeedHI
A/C SwitchON
R/F SwitchRECIRCULATION
Interior Temperature25 to 35°C (77 to 95°F)
  • NOTICE:
  • If refrigerant pressure on the high pressure side becomes high, the DTC will be stored. Therefore, it is necessary to measure the voltage for a certain amount of time (approximately 10 minutes) because the DTC may be stored after the air conditioning system operates for a while.
  • HINT:
  • When the outside air temperature is low (below -1.5°C (29.3°F)), the compressor stops due to operation of the ambient temperature sensor and the evaporator temperature sensor to prevent the evaporator from freezing. In this case, perform the inspection in a warm indoor environment.
  • OK:
  • DTC B1423 is not output.
  • NOTICE:
  • If the DTC was output due to an insufficient or excessive amount of refrigerant, the problem may have been solved after performing the previous step. However, the root cause of insufficient refrigerant may be refrigerant leaks. The root cause of excessive refrigerant may be adding refrigerant when the level was insufficient. Therefore, identify and repair the area where refrigerant leaks as necessary.
NG
Go to step 11
OK
END
11.CHECK AIR CONDITIONER PRESSURE SENSOR
Dtc B1423/23 Pressure Sensor Circuit. HEATING / AIR CONDITIONING. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Install the manifold gauge set.

Reconnect the A13 air conditioner pressure sensor connector.

Remove the air conditioning amplifier assembly with its connectors still connected.

Turn the engine switch on (IG).

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

  • Standard Voltage:
  • w/ Rear Heater:
  • Tester ConnectionConditionSpecified Condition
    E35-20 (PRE) - E35-16 (SG-2)Refrigerant pressure:
    Normal pressure (less than 3.0732 MPa [31.4 kgf/cm2, 445 psi] and more than 0.1762 MPa [1.8 kgf/cm2, 25 psi])    		1.0 to 4.8 V
    Refrigerant pressure:
    Abnormal (less than 0.1762 MPa [1.8 kgf/cm2, 25 psi])    		Below 1 V
    Refrigerant pressure:
    Abnormal (more than 3.0732 MPa [31.4 kgf/cm2, 445 psi])    		4.8 V or higher
  • w/o Rear Heater:
  • Tester ConnectionConditionSpecified Condition
    E81-9 (PRE) - E81-13 (SG-2)Refrigerant pressure:
    Normal pressure (less than 3.0732 MPa [31.4 kgf/cm2, 445 psi] and more than 0.1762 MPa [1.8 kgf/cm2, 25 psi])    		1.0 to 4.8 V
    Refrigerant pressure:
    Abnormal (less than 0.1762 MPa [1.8 kgf/cm2, 25 psi])    		Below 1 V
    Refrigerant pressure:
    Abnormal (more than 3.0732 MPa [31.4 kgf/cm2, 445 psi])    		4.8 V or higher
NG
REPLACE AIR CONDITIONER PRESSURE SENSOR ()
OK
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY ()
12.REPAIR AIR CONDITIONING SYSTEM LEAK

Identify the area where refrigerant leaks ().

Repair the identified area of the air conditioning system.

Evacuate the air conditioning system.

NEXT
CHARGE REFRIGERANT ()
13.INSPECT CONDENSER FAN
  • NOTICE:
  • For vehicles without an condenser fan, go to "CHARGE REFRIGERANT".

Inspect that the condenser fan operates normally ().

NG
REPLACE CONDENSER FAN ()
OK
14.CHARGE REFRIGERANT

Use a refrigerant recovery unit to recover refrigerant.

Evacuate the air conditioning system.

Add an appropriate amount of refrigerant ().

  • HINT:
  • If refrigerant is added and the system has not been properly evacuated (insufficient vacuum time), moisture in the air remaining in the system will freeze in the expansion valve, blocking the flow on the high pressure side. Therefore, in order to confirm the problem, recover the refrigerant and properly evacuate the system. Add an appropriate amount of refrigerant, and check for the DTC.
NEXT
15.RECHECK DTC

Recheck for the DTC when the following conditions are satisfied.

ItemCondition
Engine Speed1500 rpm
Vehicle DoorsFully open
Temperature SettingMAX COLD
Blower SpeedHI
A/C SwitchON
R/F SwitchRECIRCULATION
Interior Temperature25 to 35°C (77 to 95°F)
  • NOTICE:
  • If refrigerant pressure on the high pressure side becomes high, the DTC will be stored. Therefore, it is necessary to measure the voltage for a certain amount of time (approximately 10 minutes) because the DTC may be stored after the air conditioning system operates for a while.
  • HINT:
When the outside air temperature is low (below -1.5°C (29.3°F)), the compressor stops due to operation of the ambient temperature sensor and the evaporator temperature sensor to prevent the evaporator from freezing. In this case, perform the inspection in a warm indoor environment.
If refrigerant is added and the system has not been properly evacuated (insufficient vacuum time), moisture in the air remaining in the system will freeze in the expansion valve, blocking the flow on the high pressure side. Therefore, in order to confirm the problem, recover the refrigerant and properly evacuate the system. Add an appropriate amount of refrigerant, and check for the DTC. If the DTC is not output after this procedure, it indicates that the cooler dryer in the condenser is not able to absorb moisture in the refrigerant cycle. In this case, to complete the repair it is necessary to replace the cooler dryer.
  • OK:
  • DTC B1423 is not output.
NG
Go to step 16
OK
REPLACE COOLER DRYER ()
16.REPLACE COOLER EXPANSION VALVE

Replace the cooler expansion valve with a normal one.


for LHD ()


for RHD ()

  • HINT:
  • Replace the cooler expansion valve with a normal one because the cooler expansion valve is either stuck or clogged.
NEXT
17.CHARGE REFRIGERANT

Add an appropriate amount of refrigerant ().

NEXT
18.RECHECK DTC

Recheck for the DTC when the following conditions are satisfied.

ItemCondition
Engine Speed1500 rpm
Vehicle DoorsFully open
Temperature SettingMAX COLD
Blower SpeedHI
A/C SwitchON
R/F SwitchRECIRCULATION
Interior Temperature25 to 35°C (77 to 95°F)
  • NOTICE:
  • If refrigerant pressure on the high pressure side becomes high, the DTC will be stored. Therefore, it is necessary to measure the voltage for a certain amount of time (approximately 10 minutes) because the DTC may be stored after the air conditioning system operates for a while.
  • HINT:
When the outside air temperature is low (below -1.5°C (29.3°F)), the compressor stops due to operation of the ambient temperature sensor and the evaporator temperature sensor to prevent the evaporator from freezing. In this case, perform the inspection in a warm indoor environment.
If refrigerant pressure is not normal after replacing the expansion valve with a normal one, the condenser or pipes may be clogged due to dirt, dust or other contaminants. In this case, clean or replace the condenser or pipes.
  • OK:
  • DTC B1423 is not output.
NG
REPLACE COOLER CONDENSER ASSEMBLY ()
OK
END
HEATING / AIR CONDITIONING
Land Cruiser URJ200 URJ202 GRJ200 VDJ200
AIR CONDITIONING SYSTEM for Automatic Air Conditioning System