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Home >> Lexus >> 2024 >> RX 500h >> Repair and Diagnosis >> External Pages >> Different car >> Section 82 (Heating / Air Conditioning System - Diagnostic Codes (2 Of 3)) >> AIR CONDITIONING SYSTEM (for PHEV Model) >> DTC B3A0A-71: A/C Heating Electric Expansion Valve Actuator Stuck [08/2023 - ] >> Description

DTC B3A0A-71: A/C Heating Electric Expansion Valve Actuator Stuck [08/2023 - ]: Description

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The heating electric expansion valve (No. 2 cooler expansion valve) is installed on the inlet pipe of the cooler condenser assembly and is half open when the ignition switch is turned off. When the ignition switch is turned to ON, heat pump air conditioning control is performed to operate the stepping motor and adjust the valve opening angle of the heating electric expansion valve (No. 2 cooler expansion valve). If the heating electric expansion valve (No. 2 cooler expansion valve) is stuck closed, the amount of refrigerant flowing to the battery is reduced and cooling performance decreases.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory DTC Output from Priority Note
B3A0A-71 A/C Heating Electric Expansion Valve Actuator Stuck Diagnosis condition:
  1. During battery cooling

Malfunction status:
  1. Heating electric expansion valve (No. 2 cooler expansion valve) close stuck

Detection time:
Condition 1 
  1. Continuously for 5 minutes or more

Condition 2 
  1. Continuously for 5 minutes or more

Trip:
  1. 2 trip detection logic
  • Heating electric expansion valve (No. 2 cooler expansion valve)
  • Heat pump ECU assembly
Come on Memorized Air Conditioner A SAE Code:
  1. B3A0A

HINT: 

Battery cooling control can be performed from the Active Test of the hybrid battery system.

Refer to DATA LIST / ACTIVE TEST [08/2023 - ]