TERR

• OFF - Inhibits the GPWS enhanced modes.
• FAULT - Illuminates when failure is detected with the enhanced modes.

SYS Switch

• OFF - All GPWS warnings are inhibited.
• FAULT Light - Illuminates amber when a GPWS malfunction is detected. All GPWS warning are inhibited.

G/S Mode
Inhibits the GPWS glide slope mode.

FLAP Mode
Inhibits the GPWS Flap Mode to prevent nuisance warnings when landing with other than landing flaps.

LDG FLAP 3

• ON - Inhibits the GPWS Flap Mode to prevent nuisance warnings when landing with flaps 3.

GND CTL Switch (Spring-loaded)
Any power interruption may cause the GND CTL switch to revert to AUTO.

• ON - Energizes the cockpit voice recorder (CVR) and digital flight data recorder (DFDR). The ON light illuminates.
• AUTO - CVR and DFDR are automatically energized illuminates.
  • On the ground for the first five minutes following electrical power application.
  • On the ground with at least one engine running.
  • In flight.

The CVR and DFDR stop automatically five minutes after the last engine is shut down.

CVR Erase Switch
Erases tape when pushed for two seconds, provided the airplane is on the ground and the parking brake handle is on.

CVR Test Switch
When pushed and held, the CVR test is activated provided the CVR is energized and the parking brake handle is on. During the test, a low frequency tone is heard through the cockpit loudspeakers.