Ambient Temperature

The external ambient air temperature is measured by a sensor located behind the Land Rover badge on the front grill and is connected directly to the instrument pack.

The ambient temperature sensor is an NTC sensor whose resistance falls as the ambient temperature increases. The instrument pack outputs a reference current of 5.1V to the sensor. The instrument pack microprocessor evaluates the returned signal and converts the information into a temperature value and displays the appropriate temperature in the LCD. The temperature display can be adjusted by T4 to be displayed in either Celsius or Fahrenheit, dependent on market requirements.

The instrument pack continuously transmits the ambient temperature signals on the CAN for use by other systems, when the ignition is on. When the ignition is off, the instrument pack transmits an ambient temperature message on the I/K bus, once every 10 minutes, for a duration of 400ms.

The sensor is capable of reading temperatures in the range of -45°C (-49°F) to +56°C (+132.8°F). The instrument pack LCD will display minimum temperatures to -40°C (-40°F) and maximum temperatures to +50°C (+122°F).

The LCM monitors the temperature signals output on the bus systems. If the temperature falls to 3°C (37.4°F) or below, the LCM outputs a message signal to instrument pack, when the ignition is on. The message signal is received by the instrument pack which displays a message, 'EXTERNAL TEMPERATURE', with the recorded temperature alongside. The instrument pack also emits a single chime from the sounder to alert the driver to the warning message. The display time of the message is between 6 and 15 seconds, dependent on other displayed messages.