Operation CHARM: Car repair manuals for everyone.

Checking A/C System Cooling Performance

NOTE: A/C evaporator temperature switch -E33- (if equipped) switches A/C compressor OFF only in special instances so evaporator does not ice up, variable displacement A/C compressor maintains temperature of 0 °C (32 °F) in evaporator.

Test Conditions:
- Condenser and radiator are clean and free of obstructions
- Air distribution can be adjusted properly with ventilation control knobs
- No wiring problems detected using wiring diagram
- Outside (ambient) temperature is 20 °C-30 °C (68 °F-86 °F)

Checking:
- Start engine.
- Set fresh air blower to second speed (position 2).
- Set temperature control knob to full "cold" position (against stop).
- Adjust air distribution so air flows from instrument panel vents.
- Switch A/C on by pressing "A/C" button.
- Insert thermometer into center instrument panel outlet.
- Raise engine speed to 2000 RPM.

Specified Result:
With normal humidity and outside (ambient) temperature between 20 °-25 °C (68 °-77 °F), system is Sufficiently charged if air temperature from center instrument panel vent drops below 10 °C (50 °F) within one minute.

For higher ambient temperatures and/or higher humidity, specified air temperature from center instrument panel vent can be slightly higher.