For 1990-2009 cars

When the ignition switch is in the RUN position and either the LF door, the RF door, the RH sliding door, or the LH sliding door (if equipped) is open the ajar switch for that door closes. When the door ajar switch is closed ground is provided through G302, circuit 750, the ajar switch, and circuit 804 to the Instrument Cluster (IPC). When the IPC receives the ground input from circuit 804 it turns on the DOOR AJAR message.