B0423low severityBody
HVAC Air Temperature Sensor Circuit
on 2018 Chevrolet Malibu 2.0L I4 Turbo · FWD
What this code means
The HVAC air temperature sensor circuit is reading out of range or has failed. This affects the automatic climate control system's ability to regulate cabin temperature.
Symptoms
- Inaccurate cabin temperature control
- HVAC blows wrong temperature air
- Climate control display errors
Common causes
- Faulty air temperature sensor
- Damaged sensor wiring or connector
- Corroded connector pins
- HVAC control module fault
Diagnostic steps
- Scan for HVAC-related codes
- Check sensor connector and wiring
- Measure sensor resistance vs temperature
- Compare readings to service data specs
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Other Body codes on this vehicle
B0001
Driver Frontal Stage 1 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0005
Driver Knee Airbag Deployment Circuit
B0006
Passenger Knee Airbag Deployment Circuit
B0007
Rear Left Side Airbag Deployment Circuit
B0008
Rear Right Side Airbag Deployment Circuit
B0009
Rear Center Airbag Deployment Circuit
B0010
Driver Side Airbag Deployment