Perform the following procedure in order to ensure proper heat output of the heater system.

1. With the engine sufficiently cool, remove the radiator cap.
2. Start the engine.
3. Idle the engine.
4. Set the heater controls to the HTR mode.
5. Set the temperature mode fully to the RED (hot) temperature.
6. Set the blower motor speed mode to the HIGH position.
7. 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. Refer to the following table in order to determine the minimum acceptable heater output temperature.

Approximate the minimum acceptable heater output temperatures for other outside air temperatures by using the Fahrenheit scale. Round 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.