Functional Test/Check

The following operational test sequence will aid in determining whether the air conditioning electrical, air, vacuum and refrigeration systems are working properly. Temperature of the air should be at least 16°C (60°F). The air conditioning system can not be properly tested unless it is at least this warm.

The engine should be started and allowed to idle for about 20 minutes or until the engine cooling system thermostat is open.

Perform steps 1-9 on the illustration and compare vehicle response to the normal system response shown on the chart. If vehicle does not respond correctly during any of these steps, begin diagnosis as noted below:

^ Insufficient heating. Refer to Insufficient Heating or Defrosting. Insufficient Heating or Defrosting
^ Insufficient cooling. Refer to Insufficient Cooling Check. [1][2]Insufficient Cooling
^ Improper air delivery. Refer to Improper Air Delivery. Improper Air Delivery
^ Blower motor inoperative or incorrect speed.