Instrument Panel, Gauges and Warning Indicators: Description and Operation

The transmission/transfer box oil temperature warning light is grounded by the Automatic Transmission Oil Temperature Switch (X108) when the temperature of the transmission fluid exceeds 130°C (266°F). The warning light is also grounded by the Transfer Box Oil Temperature Switch (X174) when the temperature of the transfer box fluid exceeds 145°C (266°F).

When the Ignition Switch (X134) is in position III, battery voltage is applied to the Brake Indicator Check Relay (K106). The relay is energized, applying ground to the Transmission/Transfer Box Oil Temperature Warning Light as a bulb check.