DTC B14AB-7F: Heating Three-way Valve Actuator Stuck Off [08/2023 - ]: Description

WARNING: This page is about a different car, the 2025 Lexus RX 450h+ and 2024 Lexus RX 450h+. However, it is still accessible from the selected car via links, so may be relevant.

The rotation of the heating three-way valve (heater water valve assembly) valve is being driven according to control from the air conditioning amplifier assembly to change the coolant path.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	DTC Output from	Priority	Note
B14AB-7F	Heating Three-way Valve Actuator Stuck Off	Diagnosis Condition: Heating three-way valve (heater water valve assembly) operating Malfunction Status: Three-way valve operation request signal output continues, but three-way valve actual position information does not reach target position or results in malfunction Detection Time: Continuously for 55 seconds or more	Heating three-way valve (heater water valve assembly) Harness or connector Air conditioning amplifier assembly	Does not come on	-	Air Conditioner	A	-

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

DTC Output from

Priority

Note

B14AB-7F

Heating Three-way Valve Actuator Stuck Off

Diagnosis Condition:

Heating three-way valve (heater water valve assembly) operating

Malfunction Status:

Three-way valve operation request signal output continues, but three-way valve actual position information does not reach target position or results in malfunction

Detection Time:

Continuously for 55 seconds or more

Heating three-way valve (heater water valve assembly)
Harness or connector
Air conditioning amplifier assembly

Does not come on

Air Conditioner