Temperature control 2 feedback circuit fault
What it means
B0423. Temperature control 2 feedback circuit fault. The passenger air temperature actuator cannot report a valid position and the body warning light comes on.. This Chevy-enhanced code applies to Chevrolet, GMC, Buick, Cadillac, Pontiac, Oldsmobile and Saturn models that use this code.
Findings, check these first
- Faulty passenger air temperature actuator
- Actuator harness open or shorted
- Poor electrical connection at the actuator
Standard procedure
- Confirm the code with a scan tool
- Inspect the actuator and its connector for damage
- Test the actuator circuit for opens, shorts and poor connections
- Command the door with the scan tool and watch for movement
- Replace the actuator or HVAC module only after circuit tests pass
Look up another code
Press / to jump to the box. Chevy-enhanced powertrain, body, chassis and network codes.
Sources and review
Review: qualified. Read the source limits below.
- B0423 CHEVROLET Code: Meaning, Causes, and Symptoms | OBD2 Codes - OBD2 Codes
live reference page (obd2-codes.co)
Supports: CHEVROLET and GM-family meaning and likely causes for B0423
Fetched directly. B0423 reads "Temperature Control 2 Feedback".
- Code B0423 meaning and causes | OBDII.pro
live reference page (obdii.pro)
Supports: independent corroboration of the GM meaning
Fetched directly. obdii.pro is a separate publisher and gives the GM meaning as: Air Mix Door #2 Inoperative Error More details about the error B0423 and possible reasons for its occurrence.
Source caveat: obdii.pro GM meaning: "Air Mix Door #2 Inoperative Error More details about the error B0423 and possible reasons for its occurrence"
Last updated 2026-10-02.
Report a correction for B0423. Include your vehicle, the issue and a source if you have one.