Caution: Do not remove the radiator cap while the cooling system is hot. Serious personal injury may result. Only remove the radiator cap from a cool engine.

1. With the engine sufficiently cool, remove the radiator cap.
2. Start the engine.

Idle the engine.

3. Set the heater controls to the HEATER mode.

•	Set the temperature mode fully to the HOT position.

•	Set the blower motor speed mode to the HI position.

4. When the coolant flow in the radiator is visible through the filler neck, install the radiator cap.

1. When the engine is warmed up, after approximately 20 minutes of operation, drive the vehicle.
2. Use an accurate thermometer in order to determine the temperature of the outside air.
3. Use an accurate thermometer in order to determine the temperature of the air at the floor outlets with the vehicle being driven at 48 km/h (30 mph).
4. Compare the temperature readings with the minimum acceptable output temperatures.

The minimum acceptable heater output temperatures for outside air temperatures other than the temperatures shown may be approximated by using the Fahrenheit scale and rounding off the outside air temperature to the nearest 5 degrees. For every additional 5 degrees of outside temperature, allow an additional 1.8 degrees of heater output temperature when the outside temperature is below 50 degrees. Allow an additional 1.6 degrees of heater output temperature for every 5 degrees of outside temperature when the outside temperature is above 50 degrees.