Firebird V8-305 5.0L VIN E TBI (1989)
Air Conditioning Switch: Description and Operation
Computer Command Control - Throttle Body Fuel Injection
A/C "ON" Signal
This signal indicates that the A/C control switch is turned "ON" and the pressure switch is closed. The computer uses this signal to adjust the idle speed,
and on some models engages the A/C compressor clutch.