Where is the temperature sensor located on a BMW 5 Series?
2 Answers
The outdoor temperature sensor for the air conditioning system in the BMW 523Li is located beneath the drainage channel in the engine compartment. Temperature Sensor (temperature transducer): Refers to a sensor capable of detecting temperature and converting it into a usable output signal. Temperature sensors are the core components of temperature measurement instruments and come in a wide variety. Based on measurement methods, they can be divided into two main categories: contact and non-contact. According to sensor materials and electronic component characteristics, they are classified into thermal resistors and thermocouples. Contact Temperature Sensor: The detection part of a contact temperature sensor maintains good contact with the measured object, also known as a thermometer. Non-contact Temperature Sensor: Its sensitive element does not come into contact with the measured object, also known as a non-contact temperature measurement instrument. This type of instrument can be used to measure the surface temperature of moving objects, small targets, or objects with small heat capacity or rapid (transient) temperature changes, as well as to measure the temperature distribution within a temperature field.
As a long-time BMW owner, I once encountered inaccurate temperature readings, which turned out to be caused by a dirty sensor location. The ambient temperature sensor on a BMW 5 Series is typically installed in the front fascia area, such as behind the front grille or near the center at the bottom of the bumper. This design ensures accurate capture of external temperatures while avoiding interference from engine heat. Every time I wash my car, I use a water jet to remove accumulated dust, ensuring it doesn't get clogged with mud; if left untreated, the dashboard temperature display may drift, and the air conditioning can malfunction. Replacing it isn't difficult, but beginners should avoid DIY attempts to prevent damaging wire harness connections or surrounding plastic parts. The sensor is also prone to failure if exposed to severe moisture, so checking it promptly after driving in the rain is a good habit. I recommend cleaning the inlet with a soft brush—regular maintenance can extend its lifespan.
