Garmin GFC 600 User Manual

GFC 600™ Pilot’s Guide

Copyright © 2017 Garmin Ltd. or its subsidiaries. All rights reserved.

Garmin International, Inc., 1200 East 151st Street, Olathe, Kansas 66062, U.S.A.

Garmin AT, Inc.,2345 Turner Road SE, Salem, OR 97302, U.S.A.

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Garmin Corporation, No. 68, Zhangshu 2nd Road, Xizhi District, New Taipei City, Taiwan

Web Site Address: www.garmin.com

Contact Garmin Product Support at: www.flygarmin.com

For warranty information refer to: https://fly.garmin.com/fly-garmin/support/warranty-information/

Except as expressly provided herein, no part of this manual may be reproduced, copied, transmitted, disseminated, downloaded or stored in any storage medium, for any purpose without the express written permission of Garmin. Garmin hereby grants permission to download a single copy of this manual and of any revision to this manual onto a hard drive or other electronic storage medium to be viewed for personal use, provided that such electronic or printed copy

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Garmin® is a registered trademarks of Garmin Ltd. or its subsidiaries. This trademark may not be used without the express permission of Garmin.

July, 2017

190-01488-00 Rev.B

Printed in the U.S.A.

Warnings, Cautions & Notes

WARNING: Perform a thorough preflight control check to verify that there is no excessive friction, binding, or other anomalies that prevent smooth movement throughout the intended range of motion in pitch, roll, and yaw axis. Any discrepancies must be resolved prior to continued operation.

WARNING: For safety reasons, system operational procedures must be learned on the ground.

WARNING: The Garmin system, as installed in this aircraft, has a very high degree of functional integrity. However, the pilot must recognize that providing monitoring and/or self-test capability for all conceivable system failures is not practical.

WARNING: To reduce the risk of unsafe operation, carefully review and understand all aspects of the system, Pilot’s Guide documentation, the Pilot’s Operating Handbook (POH), and the Aircraft Flight Manual Supplement (AFMS). Thoroughly practice basic operation prior to actual use. During flight operations, carefully compare the Flight Director commands and autopilot response to all available navigation indications, attitude displays, and air data information. For safety purposes, always resolve any discrepancies before continued operation.

CAUTION: The system does not contain any user-serviceable parts. Repairs should only be made by an authorized Garmin service center. Unauthorized repairs or modifications could void both the warranty and the pilot’s authority to operate this device under FAA/FCC regulations.

NOTE: All visual depictions contained within this document, including screen images of the panel and displays, are subject to change and may not reflect the most current system and aviation databases. Depictions of equipment may differ slightly from the actual equipment.

NOTE: This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

Garmin GFC 600 Pilot’s Guide

190-01488-00 Rev. B

	Part Number	Change Summary
	190-01488-00	Initial release
Rev	Date	Description

AJune, 2017 Production Release

BJuly, 2017 Removed software version number

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			Table of Contents
Section 1 System Overview...................................................................................................			1
1.1	Basic Functions...................................................................................................................		1
1.2 AFCS Equipment.................................................................................................................			2
	GMC 605 Mode Controller....................................................................................................		2
	GSA 87 Servo.......................................................................................................................		4
	GI 285 Annunciator Panel.....................................................................................................		4
1.3 Interfacing Equipment......................................................................................................			5
	G500/G600 Integrated Glass Panel System ...........................................................................		5
	Aspen EFD1000....................................................................................................................		6
	GPS Navigators.....................................................................................................................		6
	VHF Nav Radios ...................................................................................................................		7
	Horizontal Situation Indicators (HSI)......................................................................................		7
	Directional Gyros (DG)..........................................................................................................		7
	Audio Panel..........................................................................................................................		8
	GTX 335/345(R) with GPS Option.........................................................................................		8
1.4 AFCS Controls.....................................................................................................................			9
	GMC 605.............................................................................................................................		9
	External Controls................................................................................................................		10
1.5	System Indications..........................................................................................................		11
	GMC 605...........................................................................................................................		11
	GI 285 Indications..............................................................................................................		12
	Garmin PFD AFCS Indications..............................................................................................		13
Section 2 Automatic Flight Control System...............................................................			15
2.1 AFCS Operation................................................................................................................			15
	AFCS Pre-Flight...................................................................................................................		15
	Engaging the Autopilot.......................................................................................................		16
	Flight Director Modes..........................................................................................................		16
	Disengaging the Autopilot...................................................................................................		17
2.2	Basic Autopilot Features................................................................................................		17
	Flight Director.....................................................................................................................		17
	Control Wheel Steering.......................................................................................................		19
	Yaw Damper.......................................................................................................................		20
	Manual Trim.......................................................................................................................		21
	Manual Electric Trim............................................................................................................		22
	Autotrim.............................................................................................................................		22
	Overspeed Protection..........................................................................................................		23
	Underspeed Protection........................................................................................................		24
2.3 Vertical Modes...................................................................................................................			27
	Vertical Mode Controls and Annunciations..........................................................................		27
	Pitch Hold Mode (PIT).........................................................................................................		28
	Level Mode (LVL)................................................................................................................		30
	Go Around Mode (GA)........................................................................................................		31
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Table of Contents

	Altitude Hold Mode (ALT)....................................................................................................	32
	Selected Altitude Capture Mode (ALTS)................................................................................	33
	Vertical Speed Mode (VS)....................................................................................................	34
	Indicated Airspeed Mode (IAS)............................................................................................	36
	Glidepath Mode (GP)..........................................................................................................	37
	Glideslope Mode (GS).........................................................................................................	39
2.4	Lateral Modes....................................................................................................................	40
	Lateral Mode Controls and Annunciations...........................................................................	40
	Roll Hold Mode (ROL).........................................................................................................	42
	Heading Select Mode (HDG)................................................................................................	43
	Navigation Modes (GPS, VOR, LOC).....................................................................................	45
	Approach Modes (GPS, VOR, LOC).......................................................................................	48
	Flying A DME Arc With A GPS Navigator..............................................................................	51
	Backcourse Mode (BC)........................................................................................................	52
2.5	Electronic Stability & Protection (ESP™)....................................................................	53
	Roll Engagement................................................................................................................	54
	Pitch Engagement...............................................................................................................	56
	Airspeed Protection.............................................................................................................	58
Section 3 Annunciations & Alerts.....................................................................................		59
3.1	Visual Annunciations and Alerts...................................................................................	59
3.2	Aural Alerts.......................................................................................................................	62
	Voice Alerts........................................................................................................................	62
	Autopilot Disconnect Alert...................................................................................................	62
Section 4 Abnormal Operation..........................................................................................		63
4.1	Suspected Autopilot Malfunction................................................................................	63
4.2	Overpowering Autopilot Servos..................................................................................	63
Appendices.....................................................................................................................................		64
Appendix A: Feature/Equipment Matrix............................................................................		64
Index....................................................................................................................................		Index-2

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System Overview

SECTION 1 SYSTEM OVERVIEW

The Garmin GFC 600 is a high-performance, attitude-based, Automatic Flight Control System (AFCS) that supports an extensive set of operating modes and safety features. The system design offers the flexibility to interface with a wide variety of avionics equipment commonly found in general aviation aircraft. The specific functions supported by the GFC 600 vary by installation. Refer to Appendix A for more information.

CAUTION: This manual covers all functions and modes that the GFC 600 can support, however it is the responsibility of the user to become familiar with the capabilities and limitations of a specific aircraft (per the Airplane Flight Manual Supplement) which may not support all the features described here.

1.1 BASIC FUNCTIONS

The GFC 600 AFCS provides the following main operating functions:

•Flight Director (FD) — The Flight Director function provides pitch and roll commands needed to guide the aircraft toward the active reference selected by the pilot. If a compatible Primary Flight Display (PFD) is installed these pitch and rolls commands are displayed on the PFD as Command Bars. When the Flight Director is active the pitch and roll commands can be hand-flown by the pilot. When the Autopilot is engaged the autopilot servos drive the flight controls to follow the commands issued by the Flight Director.

•Autopilot (AP) — The Autopilot function is provided by servo actuators which move the flight control surfaces in response to Flight Director steering commands, aircraft attitude, and airspeed. The optional pitch auto-trim function serves to relieve any sustained effort required by the pitch servo to keep the aircraft in trim.

•Yaw Damper (YD) — The optional Yaw Damper function provides Dutch Roll damping, assists in turn coordination, and provides a steady force to help maintain directional trim. If installed the YD comes on when the autopilot is engaged. It can be turned on/off independent of the autopilot and may be used during normal hand-flying maneuvers.

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System Overview

•Manual Electric Trim (MET) — The optional Manual Electric Trim uses the same servo as the auto-trim function and allows the pilot to command trim via a trim switch when the autopilot is not engaged. The MET function does not preclude the use of the aircraft’s basic mechanical trim system.

•Electronic Stability & Protection (ESP) — The ESP function provides a soft barrier to keep the aircraft within the desired operating envelope when the autopilot is not engaged. When the GFC 600 senses that the aircraft is near the defined operating limit in pitch attitude, roll attitude, high airspeed, or low airspeed, the ESP function will automatically engage one or more servos to nudge it back to the nominal operating envelope. While ESP utilizes the same sensors, processors, and actuators as the GFC 600 autopilot it is a separate mutually exclusive function. ESP can be easily overpowered by the pilot and can be disabled using the AP DISC / TRIM INT button.

1.2 AFCS EQUIPMENT

The basic GFC 600 system is comprised of the following equipment:

GMC 605 MODE CONTROLLER

The panel-mounted GMC 605 serves as the primary user interface for the GFC 600. The GMC provides autopilot and Flight Director mode selection buttons and a wheel for convenient adjustment of the pitch, airspeed, and vertical speed references. A backlit monochrome LCD displays active and armed modes, reference values, alerts, and messages.

The GMC 605 contains internal sensors which calculate the aircraft attitude, allowing the GFC 600 to operate without relying on any external source of attitude. Flight Director mode logic as well as some autopilot management functions are performed within the GMC 605 main processor.

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System Overview

The GMC 605 has extensive I/O capabilities that support interfaces to a large variety of equipment including Primary Flight Displays, Air Data Computers, GPS navigators, VHF Nav radios, Audio Panels, HSIs, and Directional Gyros (DGs). The GMC requires airspeed and altitude information, therefore if it does not have an interface to an Air Data Computer, a small Air Data Module must be attached to the back of the GMC’s mounting tray to provide basic air data information to the AFCS.

The GMC 605 features a covered USB port on the front face of the unit, allowing a convenient means of updating software and downloading diagnostics information to aid in troubleshooting.

CAUTION: The USB port is not designed to provide power or data to external consumer devices such as smart phones, cameras, or tablet computers and should not be used in flight.

GMC 605

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System Overview

GSA 87 SERVO

The GSA 87 servos provide control surface actuation as part of the autopilot, yaw damper, electric trim, and ESP functions. The GSA 87 is a ‘smart’ servo which performs most of the autopilot processing functions and offers many inherent safety features. The brushless motor and electronic torque and speed sensing capabilities provide smooth, reliable operation. The GSA 87 design incorporates an internal engagement solenoid and a gear train that allows the motor to be backdriven by the pilot in case the solenoid fails to disengage. This eliminates the need for a mechanical slip clutch along with the associated performance limitations and maintenance requirements.

GSA 87

GI 285 ANNUNCIATOR PANEL

The GI 285 Annunciator Panel provides basic AFCS status and mode annunciation for GFC 600 installations where the GMC 605 cannot be mounted within the pilot’s primary field of view and there is no PFD capable of providing the annunciations.

GI 285

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System Overview

1.3 INTERFACING EQUIPMENT

The GFC 600 is capable of interfacing with a wide variety of equipment including the following:

G500/G600 INTEGRATED GLASS PANEL SYSTEM

The GDU 620 Primary Flight Display (part of the G500/G600 Glass Cockpit system) can provide AFCS mode annunciation and alerts, Flight Director command bar display, Altitude Preselect (ALTS) capability, Heading (HDG) reference selection, and bank limit indications for the ESP function. The PFD displays AFCS reference values and bugs for Vertical Speed (VS) and Indicated Airspeed (IAS) modes. Nav source selection can be performed on the PFD and the GFC 600 will couple to the selected source for guidance. The G500/G600 systems include an Air Data Computer which provides airspeed and baro-corrected altitude to the AFCS. This is particularly beneficial when operating in Altitude Hold (ALT) mode because the autopilot will automatically synchronize to small changes resulting from an updated altimeter setting.

GDU 620

Reference the latest G500/G600 Pilot’s Guide for more detail about features related to AFCS.

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System Overview

ASPEN EFD1000

The Aspen EFD1000 can provide Flight Director command bar display, Heading (HDG) reference selection, and Nav source selection functions. The GFC 600 will couple to the selected nav source for guidance including when the EFD1000 is operated in GPSS mode.

Reference the Aspen EFD1000 Pilot’s Guide for operational details about features related to autopilot interfaces.

GPS NAVIGATORS

The GFC 600 can accept guidance from a variety of panel mount GPS navigators including those that provide Roll Steering and Glidepath commands and older models that provide only basic lateral course deviation for guidance. The WAAS-enabled Garmin GNS and GTN series navigators also provide an interface to the GMC 605 that supports improved aircraft attitude computation, thereby enhancing AFCS performance and increasing the availability of basic modes in the event of an air data failure.

The GTN 650 is an example of a compatible GPS Navigator:

GTN 650

Reference the applicable Pilot’s Guide for more information about operating the GPS navigation equipment installed in an aircraft.

NOTE: If there is more than one navigation source (GPS and/or VHF Nav) installed it is the responsibility of the user to understand the nav source selection mechanism and ensure that the GFC 600 is coupled to the intended source guidance.

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System Overview

VHF NAV RADIOS

The GFC 600 can accept VOR/Localizer and Glideslope guidance from a variety of VHF Nav receivers including stand-alone radios and those that are included as part of a Nav-Com or GPS-Nav-Com integrated navigator.

The GNC 255 is an example of a compatible VHF Nav receiver:

GNC 255

Reference the applicable Pilot’s Guide for more information about operating the VHF Nav equipment installed in an aircraft.

HORIZONTAL SITUATION INDICATORS (HSI)

The GFC 600 can accept Heading commands and Course inputs from a variety of HSIs including mechanical instruments such as the Bendix King KI 525A and Century NSD360A and electronic HSI displays such as the Sandel SN3500/4500.

DIRECTIONAL GYROS (DG)

If GFC 600 is installed in an aircraft without an HSI, the system can accept Heading commands from a variety of popular DGs that have a compatible interface. These installations do not provide a Course input to the GFC 600, therefore whenever the user selects a NAV or APR mode on the GMC 605 the Heading bug must be manually set to align with the Course pointer on the CDI.

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System Overview

AUDIO PANEL

The GFC 600 can interface to a wide variety of audio panels to provide aural alerts including the AP Disconnect tone and low Airspeed warning. The AFCS aural alerts cannot be muted or deselected via the audio panel controls. In addition to the audio panel interface, a Sonalert aural tone generator must be included with most GFC 600 installations to ensure the AP Disconnect aural is heard by the pilot if the audio panel fails or suffers a loss of power.

The GMA 345 is an example of a compatible audio panel:

GMA 345

GTX 335/345(R) WITH GPS OPTION

The GTX 335/345(R) transponders with GPS Option can provide an interface to the GMC 605 that supports improved aircraft attitude computation, thereby enhancing AFCS performance and increasing the availability of basic modes in the event of an air data failure.

GTX 345

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System Overview

1.4 AFCS CONTROLS

GMC 605

NOTE: VNAV support is a future growth function.

1

4

5

2							6
3							14
	7	8	9	10	11	12	13
		GMC 605 AFCS Mode Controller
1	AP Key	Engages/disengages the autopilot
2	FD Key	Activates/deactivates the Flight Director only. Pressing once turns
		on the director in the default vertical and lateral modes. Pressing

again deactivates the Flight Director and removes the Command Bars. If the autopilot is engaged, the key is disabled.

3YD Key Engages/disengages the yaw damper (if installed).

4LCD Display Displays AFCS modes, references, and annunciations.

5LVL Key Engages the autopilot in Level Mode (or selects Level Mode if

	autopilot is already engaged).
6 ALT Key	Selects/deselects Altitude Hold Mode

7HDG Key Selects/deselects Heading Select Mode

8NAV Key Selects/deselects Navigation Mode. Cancels GS Mode if LOC

Mode is either active or armed. Cancels GP Mode if GPS Mode is either active or armed.

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System Overview

9	APR Key	Selects/deselects Approach Mode
10	BC Key	Selects/deselects Backcourse Mode
11	VNV Key	Selects/deselects Vertical Path Tracking Mode for Vertical
		Navigation flight control (growth function)
12	IAS Key	Selects/deselects Indicated Airspeed Mode
13	VS Key	Selects/deselects Vertical Speed Mode
14	NOSE UP/DN	Adjusts the vertical mode reference in Pitch Hold, Vertical Speed,
	Wheel	Indicated Airspeed, and Altitude Hold modes

EXTERNAL CONTROLS

These controls are used for important Flight Director and autopilot functions but are not found on the GMC 605.

	Common	Typical
Control	Name	Location	Purpose
AP DISC/	Autopilot	Pilot control	Disengages the autopilot, yaw
TRIM INT	Disconnect	yoke/stick	damper, and interrupts pitch trim
button			operation; or, acknowledges an
			autopilot disconnect alert and mutes
			the associated tone.
			Holding the AP DISC / TRIM INT
			button down for five seconds will
			also disable Electronic Stability &
			Protection.
GA button	Go Around	Power lever	Selects Go Around mode.
(optional)		or instrument
		panel
MET switch	Manual	Pilot control	Commands manual electric pitch
(optional)	Electric Trim	yoke/stick	trim.
CWS switch	Control Wheel	Pilot control	Temporarily disengages the pitch
(optional)	Steering	yoke/stick	and roll servos. Upon releasing CWS
			the servos re-engage and may be
			synchronized to a new reference
			(depending on mode).

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				System Overview
	Common		Typical
Control	Name		Location	Purpose
Dimmer knob	Panel Lighting		Instrument	Adjusts the brightness of the GMC
(optional)	Dimmer		Panel	605 LCD backlight, keypad, and
				LED annunciators. If dimmer is not
				connected the GMC lighting will
				be adjusted automatically using its
				photocell.

1.5 SYSTEM INDICATIONS

GMC 605

The GMC 605 provides indications to the pilot via a monochrome LCD combined with three color LEDs that are located adjacent to the AP, FD, and YD keys.

The left side of the LCD displays lateral Flight Director modes, the center portion of the display provides vertical modes and references, and the right side of the display serves as a message area for status and alerts. Active modes and references are depicted in large letters along the upper portion of the display, with armed modes in a smaller font along the lower portion. The message area can display up to four messages simultaneously.

Text can be flashed alternating between normal display and inverse video when needed to get the pilot’s attention.

Active Lateral	Active Vertical	Mode	Status Messages and
Mode	Mode	Reference	Alerts

Armed		Lateral	Armed			Vertical
Mode				Mode
						GMC 605 LCD Display

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System Overview

The LEDs adjacent the AP, FD, and YD keys are illuminated in conjunction with other information on the LCD to provide status and alert information.

The AP, FD, and YD LEDs are illuminated in green to indicate that they are engaged. Manual autopilot and yaw damper disconnect is indicated with flashing yellow AP and YD annunciations, and red is used to indicate an abnormal disconnect or failure condition.

The FD LED flashes yellow to indicate when an active mode is dropped automatically by the AFCS.

The AP LED is illuminated in yellow when a trim failure has occurred or when a mistrim condition has developed.

AP (Autopilot) LED

FD (Flight Director) LED

YD (Yaw Damper) LED

GMC 605 LEDs

Refer to section 3.1 for more information about specific GMC 605 messages and LED annunciations.

GI 285 INDICATIONS

The GI 285 Mode Annunciator is required in installations where the GMC 605 is located outside of the pilot’s primary field of view and there is no Garmin PFD to provide mode annunciations and alerts. The left side of the GI 285 displays lateral Flight Director modes, the center portion of the display provides status information for the autopilot, yaw damper, and trim system, and the right side displays vertical modes.

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System Overview

The GI 285 can illuminate indications in multiple colors and also supports flashing annunciations when needed to get the pilot’s attention. Active modes are depicted in green and armed modes in white. Yellow is used to indicate when an active mode is dropped automatically by the AFCS.

The AP and YD annunciations are illuminated in green to indicate that they are engaged. Manual autopilot and yaw damper disconnect is indicated with flashing yellow AP and YD annunciations, and red is used to indicate an abnormal disconnect or failure condition.

The TRIM annunciation is illuminated in yellow when a trim failure has occurred or when a mistrim condition has developed.

The pilot should reference the GMC 605 message area for more information regarding failures and mistrim conditions.

GI 285 Annunciator

Refer to section 3.1 for more information about specific AP, YD, and TRIM annunciations on the GI 285.

GARMIN PFD AFCS INDICATIONS

A Garmin PFD (if installed) can display Flight Director command bars, active and armed mode annunciations, references, autopilot and yaw damper engagement status, and AFCS alerts. Bugs are displayed along with digital references for Selected Heading, Vertical Speed, Selected Altitude, and Indicated Airspeed (when GFC 600 is in IAS mode).

Refer to the G500/G600 Pilot’s Guide for more detailed information.

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System Overview

Lateral Modes

Active

Armed

Command

Bars

GPS is

Selected

Navigation

Source

Auto-		Yaw
pilot		Damper
Status		Status		Vertical Modes

Active

Armed

AFCS Status Annunciations

Selected

Altitude

Autopilot info on Garmin GDU 620 PFD

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AFCS

SECTION 2 AUTOMATIC FLIGHT CONTROL SYSTEM

NOTE: The approved Pilot’s Operating Handbook (POH) or Airplane Flight Manual (AFM) always supersedes the information in this Pilot’s Guide.

NOTE: Refer to the approved Airplane Flight Manual Supplement (AFMS) for GFC 600 specific emergency procedures.

2.1 AFCS OPERATION

AFCS PRE-FLIGHT

The pilot is expected to perform a standard pre-flight control check by moving the flight controls through their full range of motion in pitch, roll, and yaw axis to verify smooth and unrestricted operation. Any discrepancies must be resolved before flight.

Upon power-up the GFC 600 will automatically perform a Pre Flight Test (PFT) to check internal GMC 605 functions, interfaces, and servo status. While the test is in progress the GMC displays the message PFT. The GMC’s three LEDs are illuminated in yellow for 1 second and then in red for 1 second. The GI 285 (if installed) will illuminate all lateral mode annunciations in yellow for 1 second, followed by the AP YD/TRIM annunciations in yellow for 1 second, then the vertical modes in yellow for 1 second, and finally the AP/YD/TRIM annunciations in red for 1 second. Any failed LED annunciators on the GMC 605 or GI 285 should be noted and addressed by the operator.

When PFT is complete the AP Disconnect aural is played through the audio panel. If everything passed the PFT message is removed from the GMC display. If there are any failures detected the GMC displays PFT FAIL and illuminates the AP LED in red. The AP annunciation on the GI 285 will also be illuminated red.

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AFCS

ENGAGING THE AUTOPILOT

The autopilot is engaged by pressing the AP key on the GMC 605. If the Flight Director is already on the autopilot will begin following the active Flight Director commands. If the Flight Director is not on when the AP key is pressed, the Flight Director will come on with autopilot engagement in the default PIT and ROL modes.

Another way to engage the autopilot is by selecting the LVL key. This will engage the autopilot in Level mode.

The aircraft must be within the GFC 600 engagement limits (+/-50 degrees pitch and +/- 75 degrees roll attitude) in order to engage the autopilot.

FLIGHT DIRECTOR MODES

Flight Director modes are normally selected independently for the pitch and roll axes using the keys on the GMC 605 bezel. Unless otherwise specified, all mode keys are alternate action (i.e., press on, press off). In the absence of specific mode selection, the Flight Director reverts to the default pitch and/or roll modes.

Active modes are annunciated on the GMC 605’s screen in large text. Armed modes are annunciated in smaller text below the active modes and are queued to take effect as soon as capture criteria is met. Automatic transition from armed to active mode is indicated by the armed mode annunciation moving up to the active mode field and flashing for 10 seconds.

If the information required to compute an active Flight Director mode (such as air data or navigation data) becomes invalid or unavailable, the Flight Director automatically reverts to the default mode for that axis. The affected mode annunciation on the GMC 605 flashes in conjunction with the FD LED in yellow. The affected GI 285 annunciation also flashes in yellow. When such a loss occurs, the system automatically begins to roll the wings level (enters Roll Hold mode) or maintain the pitch angle (enters Pitch Hold mode), depending on the affected axis. The flashing annunciation stops when the affected mode key is pressed or another mode for the axis is selected. If after 10 seconds no action is taken, the flashing annunciation stops.

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