Ambient Temperature Sensor Circuit - HVAC
2007-2012 Nissan Altima 2.5L I4
Description
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.
Related Codes
Other Body Codes
- B0001Driver Frontal Stage 1 Deployment Control
- B0002Driver Frontal Stage 2 Deployment Control
- B0003Passenger Frontal Stage 1 Deployment Control
- B0004Passenger Frontal Stage 2 Deployment Control
- B0005Driver Knee Airbag Deployment Circuit
- B0006Passenger Knee Airbag Deployment Circuit
- B0007Rear Left Side Airbag Deployment Circuit
- B0008Rear Right Side Airbag Deployment Circuit
- B0010Driver Side Airbag Deployment
- B0011Driver Side Airbag Deployment Circuit Open
B0621 on Other Vehicles
Nissan 200SX
1995-1998 1.6L I4 GA16DE
Nissan 200SX SE-R
1995-1998 2.0L I4 SR20DE
Nissan 240SX
1995-1998 2.4L I4 KA24DE
Nissan 300ZX
1990-1996 3.0L V6 VG30DE
Nissan 300ZX Twin Turbo
1990-1996 3.0L Twin-Turbo V6 VG30DETT
Nissan 350Z
2003-2006 3.5L V6 VQ35DE
Nissan 350Z
2007-2009 3.5L V6 VQ35HR
Nissan 370Z
2009-2020 3.7L V6 VQ37VHR
Common Questions
What does code B0621 mean on a 2007-2012 Nissan Altima?
B0621 stands for "Ambient Temperature Sensor Circuit - HVAC". Malfunction in the ambient (outside) temperature sensor used by the automatic climate control system.
What are the symptoms of B0621 on a Nissan Altima?
Common symptoms of B0621 include: Incorrect outside temp display, Auto climate control not adjusting for outside temp, A/C compressor may not engage, Defrost strategy incorrect.
What causes B0621 on a 2007-2012 Nissan Altima?
Common causes of B0621 include: Faulty ambient sensor, Sensor mounted near heat source, Wiring damage, Sensor connector corroded.