B0621low severityBody
Ambient Temperature Sensor Circuit - HVAC
on 2004 Mazda Mazda3 2.3L I4 · FWD
What this code means
Malfunction in the ambient (outside) temperature sensor used by the automatic climate control system.
Symptoms
- Incorrect outside temp display
- Auto climate control not adjusting for outside temp
- A/C compressor may not engage
- Defrost strategy incorrect
Common causes
- Faulty ambient sensor
- Sensor mounted near heat source
- Wiring damage
- Sensor connector corroded
Diagnostic steps
- Compare sensor reading to actual outside temperature
- Inspect sensor location for heat sources
- Test sensor resistance
- Check wiring
- Inspect connector
Repair notes
Replace ambient temperature sensor. Ensure it is properly mounted away from heat sources.
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
B0010
Driver Side Airbag Deployment
B0011
Driver Side Airbag Deployment Circuit Open
B0012
Driver Side Airbag Deployment Circuit Short to Ground
B0013
Driver Side Airbag Deployment Circuit Short to Battery