SAAB WIS ONLINE

Ambient temperature sensor

Ambient temperature sensor





General

The ambient temperature sensor is mounted in the centre of the lower spoiler and provides the SID with information on the current ambient temperature. The sensor is an NTC resistor.

The SID measures the ambient temperature by supplying the sensor with +5 V via a resistor (10 kohm) in the control module. The sensor is supplied via pin 19 and grounded via pin 20.

The voltage across the integral resistor in the SID unit is proportional to the ambient air temperature. The SID unit uses the ambient temperature for the trip computer function and the reading is sent as bus information AMBIENT TEMP, unit °C,

Diagnosis

If there is a break/short to ground in the circuit to the ambient temperature sensor, diagnostic trouble code B1746 will be generated.

If there is a short circuit to B+, fuse 8 will blow.