Perform the following steps in order to determine whether or not the air conditioning, electrical, vacuum and refrigeration systems are operating properly:

1. Operation of the air conditioning blower at all 4 speeds with the mode lever in any position except OFF and engagement of the compressor clutch will indicate that the electrical circuits are functioning properly.

The blower will not operate in any speed with the mode lever in the OFF position.

2. The same HAND-FELT temperature of the evaporator inlet pipe and the accumulator surface of an operating system will indicate a properly charged system.
3. Operation of the Heater and A/C mode lever in order to distribute air from the appropriate outlets indicate proper operation.

The system will default to air flow in several modes if a vacuum system malfunction exists.