A/C High Pressure Switch: Removal

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Recover the refrigerant the system. See RECOVERY, EVACUATION & RECHARGING in GENERAL SERVICING PROCEDURES article in GENERAL SERVICING. Clean the control A/C high pressure switch area before removing the snap ring. Disconnect the electrical connector from the A/C high pressure switch.
Remove the A/C high pressure switch snap ring using a pair of 90 degree angle pliers or Snap Ring Pliers. Remove the A/C high pressure switch from the compressor. See Fig 1. Remove the old O-ring seal from the A/C high pressure switch cavity using the O-Ring Remover.
Inspect the A/C high pressure switch cavity and the O-ring groove in the rear head for dirt or foreign material. Clean the components as necessary.

Fig 1: Removing & Installing A/C High Pressure Switch
Courtesy of GENERAL MOTORS CORP.