BCM Code F10 - Outside Air Temperature Sensor Circuit: Notes
NOTE:
If this code is not displayed during second pass of diagnostic codes, it is an intermittent failure and cannot be diagnosed using this procedure. See NOTE ON INTERMITTENTS.
Outside air temperature sensor uses a thermistor to control signal voltage to BCM. BCM applies and monitors voltage on circuit No. 735 to sensor. When sensor is cold, its resistance is high; therefore, BCM will see a high monitored voltage. As sensor warms, its resistance becomes less; signal voltage is pulled low through sensor ground circuit No. 736. This signal voltage will vary between 5 volts (open circuit) and zero volts (shorted circuit).
BCM Code F10 will set if temperature is less than -29°F (-34°C) (circuit open) or greater than 189°F (87°C) (circuit shorted). These conditions can be observed in BCM data display (parameter P.2.6) as a reading outside range of -29°F to 189°F (-34°C to 87°C).
NOTE:
Test numbers refer to numbers on diagnostic chart.
- If temperature reading changes after disconnecting sensor, BCM and wiring are okay.
- If temperature reading changes after jumpering sensor terminals, BCM and wiring are okay.
- By applying ground to various points in circuits, an open can be isolated when temperature display changes from less than -29°F (-34°C) to greater than 189°F (87°C).