Code Definition

B0424 — Air temperature/mode door actuator Circuit malfunction

System: Body  |  Type: Generic (OBD-II Standard)  |  Make: Generic

About B0424

B0424 is a generic (obd-ii standard) body diagnostic trouble code. It belongs to the B-prefix family of codes, which covers body, interior, airbag, or comfort-electronics faults.

When B0424 is stored, the module has detected an electrical-circuit fault in the wiring, connector, or driver associated with the named component.

Scanning & clearing: Body (B) codes are often stored in the body control module, airbag module, or climate module. A basic OBD-II tool usually will not read body codes — an enhanced or OEM-level scan tool is typically required.

Because B0424 is a generic OBD-II code, its base definition is shared across manufacturers. The specific diagnostic steps, reference values, and repair procedures can vary by vehicle, and the TaT Diagnostic Assistant includes verified procedures submitted by working technicians.

Code Information

DTC B0424 is a generic body code that indicates the HVAC control module has detected an electrical malfunction in the circuit for an air temperature (blend) or mode door actuator. These small DC stepper or potentiometer-feedback actuators reposition the doors inside the HVAC case to control airflow temperature and distribution between vent, floor, and defrost outlets, and the module monitors both the motor drive command and the position feedback signal. The code sets when the feedback does not agree with the commanded position, when the motor draws abnormal current, or when an open or short is...

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