A/C Performance Testing

WARNING: Review SAFETY PRECAUTIONS AND WARNINGS before proceeding With this procedure.

Air temperature in test room and on vehicle must be 70°F (21°C) minimum for this test.

Performance Temperature Chart:

1. Connect a tachometer and manifold gauge set.
2. Set control to A/C, RECIRC, PANEL, or MAX A/C, temperature lever on full cool and blower on high.
3. Start engine and hold at 1000 rpm with A/C clutch engaged.
4. Engine should be warmed up with doors and windows closed.
5. Insert a thermometer in the left center A/C outlet and operate the engine for five minutes. The A/C clutch may cycle depending on ambient conditions.
6. With the A/C clutch engaged, compare the discharge air temperature to the A/C PERFORMANCE TEMPERATURES chart.
7. Operate the A/C for two more minutes and take the discharge air temperature reading again. If the temperature increased by more than 51°F (21°C), check the blend air door for correct operation. If the temperature does not increase more than 51°F (21°C), compare the discharge air temperature, suction and discharge pressures. These can be found in the A/C PERFORMANCE TEMPERATURES chart.
8. If the discharge air temperature fails to meet the specifications in the performance temperature chart, refer to Refrigerant System Diagnosis.