(8) HOLD button - Depress to restore the display to normal.
Automatic Leg Switching - Check as follows:
(1) ROLL LIM key - 25° (dim) for the first waypoint.
(2) ROLL LIM key - 10° (lighted) for second waypoint.
(3) Check that the aircraft changes course smoothly.
Attitude Mode - Check as follows:
(1) Mode selector - ATT after passing the starting point and observing the present position.
(2) Check that INS attitude signals continue to be available by monitoring instruments.
(3) Check that the instruments can operate from other navigation signals not coming from the INS.
*4. Audio control panel and interphone system - Check each unit as follows:
Interphone functional check:
(1) Receiver selector switches - OFF.