B0258
HVAC Air Mix Door 1 Circuit
The HVAC controller reports a fault in the actuator circuit for air mix door 1, which controls the proportion of warm and cool air in the airflow.
The HVAC controller reports a fault in the actuator circuit for air mix door 1, which controls the proportion of warm and cool air in the airflow.
Common causes
- high
Air mix door actuator motor failed
One of the most commonly reported causes for this code — check this first.
Typical part cost: $90-550
- medium
Mix door jammed by debris
A plausible cause — test and verify before replacing parts.
Typical part cost: $90-550
See all causes + fix costs
Create a free Wrenchify account to unlock the rest for B0258.
Unlock causesFree forever · No credit card
First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
Get the full step-by-step diagnosis
Create a free Wrenchify account to unlock the rest for B0258.
Unlock diagnosisFree forever · No credit card
Related codes
See related trouble codes
Create a free Wrenchify account to unlock the rest for B0258.
Unlock related codesFree forever · No credit card
Frequently asked questions
What does B0258 mean?
B0258 means "HVAC Air Mix Door 1 Circuit". It is a generic OBD-II code that points to a fault in the body.
What are the most common causes of B0258?
air mix door actuator motor failed; mix door jammed by debris; open wiring to actuator — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
Get the full B0258 diagnosis for your vehicle
Year, make, model + step-by-step repair help — free plan included.