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A/C Signal: Description and Operation

A/C "ON" Signal Circuit:






NOTE: Because different models and engine applications vary in wire colors, circuit numbers, and pin numbers, the above image is a typical example. Refer to COMPUTERS AND CONTROL SYSTEMS/SCHEMATIC AND ROUTING DIAGRAMS for specific schematic applications.

PURPOSE:

This signal indicates that the A/C control switch is turned "ON" and the pressure switch is closed. The control module uses this signal to adjust the idle speed for improved idle and engine performance.