Functional Test

TXV A/C System:

Psi-Temp Relationship Of R-12:

SYSTEM INSPECTION
^ If a malfunction in the refrigerant system is suspected, check the following:
1. Check outer surfaces of radiator and condenser cores to be sure air flow is not blocked by dirt, leaves or other foreign material. Be sure to check between the condenser and radiator as well as the outer surfaces.
2. Restrictions or kinks in the condenser core, hoses, tubes, etc.
3. Blower motor operation.
^ Refer to blower motor wiring diagrams and system diagnosis.
4. Refrigerant leaks.
5. Check all air ducts for leaks or restrictions. Low air flow rate may indicate a restricted evaporator core.
6. Compressor clutch slippage.
7. Improper drive belt tension.
8. Plugged receiver dehydrator or thermal expansion valve.
9. Excessive moisture in the refrigerant system.
10. See System Diagnostic Tests. Testing and Inspection
11. Check cooling fan for normal operation.
12. Check coolant thermostat for normal operation.

Functional Test Chart:

A/C OPERATIONAL TEST
To help in determining whether or not the air conditioning, electrical, vacuum and refrigeration systems are operating properly, refer to the Functional Test Chart and perform the following:

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. Operation of the A/C control selector (mode) lever to distribute air from the appropriate outlets indicate proper operation. The system will default to the defroster vents if a vacuum system malfunction exists.