A/C Signal: Description and Operation
PURPOSE
To signal the Programmed Fuel Injection Electronic Control Module (PGM-FI ECM) to increase idle speed when the demand for cooling from the air conditioning system causes the idle to drop.
OPERATION
When the air conditioning is operated a signal is sent to the PGM-FI ECM which then commands the Idle Air Control Valve (IAC) to raise the idle speed compensating for the increased engine load.