BCM Code F11 - A/C High Side 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.
A/C high side temperature sensor uses a thermistor to control signal voltage to BCM. BCM applies and monitors voltage on circuit No. 732 to sensor. When sensor is cold, its resistance is high; therefore, BCM will see a high signal voltage. As sensor warms, its resistance becomes less and monitored signal voltage is pulled low through sensor ground, circuit No. 736. This signal voltage will vary between 5 volts (circuit open) and zero volts (circuit shorted).
BCM Code F11 will set if signal voltage indicates an open circuit, 16°F(-9°C), or a shorted circuit, 408°F (209°C). These conditions can be observed in BCM data display (parameter P.2.7) as a reading outside range of 16°F to 408°F (-9°C to 209°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 about 59°F to 392°F (-15°C to 200°C).