Ambient Temperature Sensor Inspection

Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
Remove the front bumper. (See FRONT BUMPER REMOVAL/INSTALLATION .)
Remove the ambient temperature sensor. (See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
Measure the temperature around the ambient temperature sensor and measure the resistance between the ambient temperature sensor terminals A and B.

Fig 1: Identifying Ambient Temperature Sensor Connector Terminals
Courtesy of MAZDA MOTORS CORP.
- If the characteristics of the ambient temperature sensor are not as shown in the graph, replace the ambient temperature sensor. (See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
  
  Fig 2: Ambient Temperature Sensor Resistance Graph
  Courtesy of MAZDA MOTORS CORP.