A/C Cycling Switch

A/C CYCLING SWITCH

The A/C cycling switch is mounted on a Schrader valve-type fitting on the suction accumulator.
- A valve depressor, located inside the threaded end of the A/C cycling switch, presses in on the Schrader valve stem.
- This allows the suction pressure to control the operation of the A/C cycling switch.
- Battery voltage is present at one side of the A/C cycling switch at all times when the ignition switch is in the RUN position.
- When the switch contacts are closed, the battery voltage circuit is completed to the PCM to signal that the low-side refrigerant system pressure is acceptable for A/C compressor operation.
- When the switch contacts are open, the battery voltage circuit is opened to signal the PCM that the low-side refrigerant system pressure is too low for A/C compressor operation.
- The A/C cycling switch will control the evaporator core pressure at a point where the plate/fin surface temperature will be maintained slightly above freezing.
- This prevents icing of the evaporator core and blockage of airflow.
- It is not necessary to recover the refrigerant to remove the A/C cycling switch.