GNS 400W Series Installation Manual Page 4-9190-00356-08 Rev. G4.5 Annunciators/Switches4.5.1 Annunciators/Switches Function4.5.1.1 Message AnnunciateWhen a new status message is available, the Message Annunciator flashes. When status messagesremain effective, the Message Annunciator illuminates.4.5.1.2 Waypoint AnnunciateThe waypoint annunciator output is driven in the following manner:1. When the aircraft is within 10 seconds of reaching the turning point for a course change, thewaypoint annunciator flashes.2. When the aircraft is in a turn, the waypoint annunciator illuminates and remains illuminated untilthe turn is completed.3. When a user arrival alarm is set and the aircraft is within the circle defined by the arrival alarmradius at the arrival waypoint, the waypoint annunciator flashes for 10 seconds.4. When a user arrival alarm is not set and the aircraft is within 10 seconds of reaching the arrivalwaypoint, the waypoint annunciator flashes.4.5.1.3 CDI SOURCE SELECT (GNS 430W Only)This discrete input may be used to toggle between display of GPS and VOR/LOC/Glideslope informationon the MAIN external CDI/HSI. A momentary low on this pin performs the same function as pressingthe ‗CDI‘ key on the GNS 430W bezel.4.5.1.4 VLOC ANNUNCIATE (GNS 430W Only)This annunciator output is driven when the unit is configured with a single CDI/HSI and the VOR/ILSdata is being displayed on the CDI/HSI. This output parallels the VLOC annunciator on the display.4.5.1.5 GPS ANNUNCIATE (GNS 430W Only)This annunciator output is driven when the unit is configured with a single CDI/HSI and the GPS data isbeing displayed on the CDI/HSI. This output parallels the GPS annunciation on the display.4.5.1.6 OBS MODE SELECTThis discrete input may be used to toggle between GPS OBS and GPS AUTO modes of operation. Amomentary low on this pin performs the same function as pressing the ‗OBS‘ key on the 400W Seriesunit.4.5.1.7 OBS ANNUNCIATEThis annunciator output is driven to indicate GPS OBS mode of operation. This output is active when theOBS or SUSP annunciation is on the display.4.5.1.8 TERMINAL ANNUNCIATEWhen performing approach navigation, the terminal annunciator is illuminated when operating within 30nautical miles of the departure or arrival airport and the CDI scale is the equivalent or 1.0 nm or less.