B1238 The climate control unit found a problem in the passenger side air mix linkage, door, or motor
What does B1238 mean on a Honda?
B1238. The climate control unit found a problem in the passenger side air mix linkage, door, or motor. The passenger side temperature may not change when you adjust it. This Honda-enhanced code applies to Honda and Acura models that use this code.
Common causes of B1238
- Faulty passenger side air mix control motor
- Binding or damaged air door or linkage
- Passenger side air mix control motor harness is open or shorted
- Passenger side air mix control motor circuit poor electrical connection
- Faulty climate control unit
How to fix B1238
- Confirm the code with a scan tool and check the climate control for related faults
- Inspect the linkage and air door for binding, broken parts, or debris
- Test the motor and its position feedback at the connector
- Check the wiring for an open or short before replacing parts
- Replace the passenger side air mix control motor only if it and the linkage fail testing, then clear codes and retest
Sources and review
- Last updated 2026-09-29.