DTC B1423: Open in Pressure Sensor Circuit / Abnormal Refrigerant Pressure [07/2022 - ]: Description

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus UX 250h, 2023 Lexus UX 250h, 2022 Lexus UX 250h, 2021 Lexus UX 250h, and 2020 Lexus UX 250h. However, it is still accessible from the selected car via links, so may be relevant.

This DTC is stored if refrigerant pressure on the high pressure side is extremely low (176 kPa (1.8 kgf/cm² , 26 psi) or less) or extremely high (3025 kPa (30.8 kgf/cm² , 439 psi) or more). The air conditioner pressure sensor, which is installed to the high pressure side pipe to detect refrigerant pressure, sends a refrigerant pressure signal to the air conditioning amplifier assembly. The air conditioning amplifier assembly converts this signal to a pressure value according to the sensor characteristics and uses it to control the compressor.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Memory
B1423	Open in Pressure Sensor Circuit / Abnormal Refrigerant Pressure	Open in air conditioner pressure sensor circuit Short in air conditioner pressure sensor circuit Refrigerant pressure on high pressure side is extremely low (176 kPa (1.8 kgf/cm² , 26 psi) or less) or extremely high (3025 kPa (30.8 kgf cm² , 439 psi) or more)	Air conditioner pressure sensor Harness or connector Air conditioning amplifier assembly 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) Cooling fan system (cooler condenser assembly cannot be cooled down) Air conditioning system (leaks, blocked) Refrigerant volume (excessive, low)	-

DTC Detection Conditions

		Vehicle Condition
		Pattern 1	Pattern 2	Pattern 3
Diagnosis Condition	Power switch on (IG)	◦	◦	◦
Malfunction Status	Open in air conditioner pressure sensor circuit	◦	-	-
	Short in air conditioner pressure sensor circuit	-	◦	-
	Refrigerant pressure on high pressure side is extremely low (176 kPa (1.8 kgf/cm² , 26 psi) or less) or extremely high (3025 kPa (30.8 kgf cm² , 439 psi) or more)	-	-	◦
Detection Time		-	-	-
Number of Trips		1 trip	1 trip	1 trip

HINT:

DTC will be output when conditions for either of the patterns in the table above are met.