Garmin GMA 340 User manual

GMA 340 AUDIO PANEL
JUIAINTENANCE MANUAL
Garmin International
1200 E. 151" Street
Olathe,
KS 66062 USA
1 90-00 1 49-02 (Rev B)
June 2001
3
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0 Copyright 1998-2001
GAMIN Corporation
All Rights Reserved
REVISION REVISION
DATE
A 1/4/99
B 61710 1
Except as expressly provided herein, no part ofthis manual may be reproduced, copied, transmitted, disseminated, downloaded or
stored in any storage medium, for any purpose without the express prior written consent of GARMIN Corporation. GARMIN
Corporation 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 and to print one copy of this manual or of any revision hereto, provided that
such electronic or printed copy of this manual or revision must contain the complete text of this copyright notice and provided
hrtherthat any unauthorized commercial distribution ofthis manual or any revision hereto is strictly prohibited.
DESCRIPTION ECO #
-
Initial Release
Add 340 Dual ADF and field replacement of main board.
15949
GARMIN International, Inc.
1200 E. 15lStStreet
Olathe,
KS 66062 USA
Telephone: [phone],Dealer Line: 1-800-800-1420
Web SiteAddress:
www.mrmin.com
INFORMATION SUBJECT TO EXPORT CONTROL LAWS
This document may contain information which is subject to the Export Administration Regulations ("EAR") issued by the United
States Department of Commerce
(1 5 CFR, Chapter VII, Subchapter C) and which may not be exported, released, or disclosedto
foreign nationals inside or outside of the United States without first obtaining an export license. A violation of the EAR may be
subject to
a penalty of up to 10 years imprisonment and a fine ofup to $1,000,000 under Section 2410 of the Export
Administration Act of
1979. Include this notice with any reproduced portion ofthis document.
190-00 149-02Rev B
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TABLE OF CONTENTS
SECTION 1
DESCFUPTIONAND OPERATION
PARAGRAPH PAGE
1.1 INTRODUCTION
............................................................................................................................. 1-1
1.2 GENERAL DESCRIPTION
.............................................................................................................. 1-1
1.3 THEORY OF OPERATION ............................................................................................................. 1-2
SECTION 2
SPECIAL TESTEQUIPMENT
2.1 INTRODUCTION ............................................................................................................................. 2-1
2.2 GMA 340 REAR CONNECTORS
.................................................................................................... 2-1
2.3 GMA 340 TEST PANEL
.................................................................................................................. 2-1
2.4 TEST HARNESS.
J 1 AND 52 PIN ASSIGNMENTS ...................................................................... 2-4
SECTION 3
TROUBLESHOOTING
3.1 TROUBLESHOOTING .................................................................................................................... 3-1
3.2 TROUBLESHOOTING PROCEDURES .......................................................................................... 3-1
3.3 POWER ON CHECK
........................................................................................................................ 3-5
3.4 28
V LIGHTING ............................................................................................................................... 3-5
3.5 14
V LIGHTING ............................................................................................................................... 3-5
3.6 PTT ANNUCIATOR CHECK .......................................................................................................... 3-5
SECTION 4
DISASSEMBLY AND REASSEMBLY
4.1 INTRODUCTION ............................................................................................................................. 4-1
4.2 TOOLS REQUIRED
......................................................................................................................... 4-1
4.3 DISASSEMBLING THE UNIT
........................................................................................................ 4-1
4.4 REASSEMBLY
................................................................................................................................. 4-3
190-00 149-02 Rev B I
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SECTION 5
TESTING
5.1 GENERAL ......................................................................................................................................... 5-1
5.2 ADJUSTMENT/MEASUREMENT ACCURACY
.......................................................................... 5-1
5.3
5.4
5.5
5.6 TEST PANEL
.................................................................................................................................... 5-2
5.7 BENCH TESTING
............................................................................................................................ 5-2
5.8 TEST EQUIPMENT SETUP
............................................................................................................ 5-2
5.9 STANDARD TEST SIGNALS ......................................................................................................... 5-5
5.10 POWER OFF CHECK
...................................................................................................................... 5-6
5.1
1 POWER ON CHECK ........................................................................................................................ 5-6
5.12 LOADED MICROPHONE VOLTAGE INPUTS
............................................................................. 5-7
5.13 PILOT PTT TESTS
........................................................................................................................... 5-7
5.14 FUNCTIONAL TEST ....................................................................................................................... 5-8
TEST EQUIPMENT PRECAUTIONS
............................................................................................. 5-1
REQUIRED TEST EQUIPMENT
.................................................................................................... 5-2
REAR CONNECTORS PRECAUTION
........................................................................................... 5-1
SECTION 6
REPLACEABLEASSEMBLIES
6.1 LIST
OF REPLACEABLE PARTS .................................................................................................. 6-1
SECTION 7
ASSEMBLY DRAWINGS
7.1 ASSEMBLY DRAWINGS ............................................................................................................... 7-1
11 190-001 49-02 Rev B
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LIST OF FIGURES
FIGURE PAGE
2-1 GMA 340 Rear Connectors (Viewed from the Rear)
........................................................................ 2-1
2-2 Typical Test Panel Layout
................................................................................................................. 2-3
2-3 Test Panel Schematic Diagram
.......................................................................................................... 2-6
2-4 Coax Cable Assembly
..................................................................................................................... 2-10
3-1 Front Panel Connector Detail
............................................................................................................ 3-2
3-2
3-3
5-1 GMA 340 Test Connections .............................................................................................................. 5-3
7-1 GMA 340 Front Panel Assembly
...................................................................................................... 7-1
7-2 Marker Lamp Rack Assembly. Front and Rear Detail
...................................................................... 7-1
7-3 GMA 340 Final Assembly
................................................................................................................. 7-2
Main Board Component Location. Partial Layout
............................................................................ 3-3
Power Input Board
............................................................................................................................. 3-4
LIST OF TABLES
Table PAGE
2.1
. Test Panel Parts List .......................................................................................................................... 2-2
2.2
. J1 and 52 Pin Assignments ................................................................................................................ 2-5
3.1. Front Panel Connector Detail
............................................................................................................ 3-2
3-2 Main Board Connector Detail
........................................................................................................... 3-3
3.3. Power Input Board Connector Detail
................................................................................................ 3-4
Field Replaceable Parts List
.............................................................................................................. 6-1
6-1
...
190-00149-02 Rev B 111
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iv 190-001 49-02 Rev B
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SECTION 1
DESCRIPTION AND OPERATION
1.1 INTRODUCTION
This manual provides functional testing and assembly-levelrepair information for the GARMIN GMA 340,
GMA 340H and GMA 340 Dual ADF Audio Panels. Reference to GMA 340 throughout this manual refers to all
versions of the unit. Information pertaining to the installation and operating instructions can be found in the
GMA 340 Audio Panel Installation Manual, 190-00149-0
1. This manual is designed to aid the bench technician
in isolating failures
co the assembly level only. If necessary, the GMA 340 can be returned to GARMIN for all
service work, including maintenance and repair. Contact GARMIN at the following address for more details:
GARMIN
1200 E. 151st Street
Olathe,
KS 66062
1-913-397-8200 or 1-800-800-1020
1.2 GENERALDESCRIPTION
The GARMIN GMA 340 is a panel mounted TSO’d audio panel that provides control of the aircraft audio
system. The GMA 340 provides flexibility in switching up to three microphone and audio transceiver
communication inputs. Audio selection ofNAV 1,NAV 2, ADF, DME and marker audio is available on the
GMA 340 and GMA 340H. In addition, selection of ADF 1and ADF 2 is provided on the GMA 340 Dual ADF.
The GMA 340 includes a voice activated (VOX) intercom system and a three-lamp marker beacon receiver and
display. One or two stereo entertainment inputs are also provided. (One on the GMA 340 Dual ADF, two on the
other units.)
The VOX intercom uses rotary knobs for volume and squelch adjustment while selection of
all other functions is
accomplished with the use of pushbuttons.
Marker HI and LO and button annunciation is accomplished with LED devices. Front panel backlightingof
button function, squelch and volume control knobs is provided by LED’Scontrolled by the aircraft lightingbus.
On the GMA 340 and GMA 340H the split com function allows the pilot and copilot to talk on Com
1 and Com 2
simultaneously.
The unit is constructed from high quality materials and uses surfacemount components extensively. Specialized
equipment and procedures are required to repair circuit boards having surface-mounted components. GARMIN
does not authorize the repair of GMA 340 circuit boards. If necessary, circuit boards and assemblies for the
GMA 340 can be economically replaced through the GARMIN board exchange program.
The following assemblies and printed circuit boards can be field replaced:
0
Front Panel Assembly-Contains the front panel bezel, button key cap assembly, marker beacon lamp
assembly and front panel board assembly.
0
Marker Beacon Lamp Rack Assembly-Contains marker beacon incandescent lamps and lamp rack.
Fits onto the front panel assembly.
0
Flexible Circuit Cables-Connects the frontpanel to the main circuit board assembly.
190-00149-02 Rev B 1-1
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Power Input Board Subassembly-Contains filtering components for the aircraft power line, panel
lighting bus and speaker ground line. Fits onto the main board assembly.
0
Main Board Subassembly-Contains the main operating circuits for the unit. Fits onto the chassisframe.
Installation Screw Shaft-Secures the unit chassis into the mounting rack.
0
1.3 THEORY OF OPERATION
Internallythe GMA 340 is divided into three printed circuit boards: Main Board, Front Panel Board and Power
Input Board.
1.3.1 Power Input Board Assembly
The Power Input Board Assembly accepts three power-signal inputs; aircraft power, panel lightingbus line and
the speaker ground line from the main board. The main power input, the panel lighting lines and speaker ground
line are filtered before returning to the main board.
1.3.2 Main Board Assembly
The Main Board Assembly contains the main operating circuits for the audio panel. It accepts audio inputs from
the various pilot and passenger microphones and directs them to the appropriate output. It also accepts audio
from the aircraft avionics receivers and conditions the signals for use among the various phone and speaker
outputs.
The Main Board Assembly also contains the Marker Beacon Receiver. The marker receiver accepts the
75 MHz
signal from the Marker Beacon Antenna. The receiver attenuates the signal to the desired level for either high or
low sensitivity.
The marker beacon circuit detects the 400
Hz, 1300 Hz, and 3000 Hz marker tones. By means of audio filters,
the circuit lights the appropriate marker lamp as the signal is received.
The detected audio tones are also passed to the audio output. When marker audio
is present, the tones are heard
on the speaker or phones.
A mute circuit quiets the audiotone when the MKWMUTE button is pressed and automatically rearms the audio
circuit for the next received marker.
1.3.3 Front Panel Board Assembly
The Front Panel Board Assembly contains the panel lighting, button annunciator
LED’S, front panel button
switches and the marker beacon lamps.
1-2 190-00149-02 Rev B
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SECTION 2
SPECIALTEST EQUIPMENT
2.1 INTRODUCTION
This section describes special test equipment required for testing the GMA 340 Audio Panel. The Test Panel and
associated cables identified in this section may be fabricated locally accordingto the diagrams and parts
information given. Standard test equipment is listed in Section
5, TESTING. For any questions regardingthe
operation of the special test equipment listed in this section, contact the GARMIN Product Support Department
at the address or telephone number given in Section
1.
2.2 GMA340 REAR CONNECTORS
Connectors J1 and 52 are identical. Test harness misconnection could cause
permanent damage the GMA 340 unit.
The GMA 340 contains two 44-pin connectors designated J1 and 52 located at the rear of the unit. When viewed
from the rear the connectors appear as shown in Figure 2-1.
To avoid misconnection to the unit it is
recommended that the test harness connectors be secured to a fixture or unit rack mount.
000000000000000
OOOOOOOOOOOOOO
44 44
J2 J1
Figure 2-1. GMA 340 Rear Connectors (Viewed from the Rear)
2.3 GMA340 TEST PANEL
The GMA 340 Test Panel provides the necessary test voltages and test points for testing the GMA 340. A panel
such as the one shown
in Figure 2-2 or equivalent is required to test the GMA 340. A correspondingtest panel
layout, schematic diagram and test panel parts list is provided.
190-00149-02 Rev B 2-1
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Item
RG-188A Coax
Hookup Wire, 24 AWG
Hookup Wire, 22 AWG
2 Conductor Shielded Twisted Pair, 24 AWG
3 Conductor Shielded Twisted Pair, 24 AWG
Banana Jack. Red
Hi Density D-Sub Connector, Male, 44 Contacts
Quantity
As Required
As Required
As Required
As Required
As Required
2
2
Rotary Switch,
2 Pole, 20 Position
Toggle Switch, SPDT
Toggle Switch. DPDT
Banana Jack, Black
Banana Jack, Green
Tip Jack
BNC Female Insulated Connector
.250 Jack,
3 Conductor, Insulated
.2
11 Jack, 3 Conductor
Shoulder Washer, Insulated
3.5mm Jack. 3 Conductor
Switch, Pushbutton, On/Off
Capacitor, Ceramic, 0.01uF, 20%, SOVDC
2
1
19
3
3
6
6
2
I Resistor. 24 Ohm. 1OW II 6 I
Resistor, 470 Ohm, 1/4W, 5%
Resistor, 1K, 5W, 5%
Resistor, 4.7k, 1/4W, 5%
Resistor, 56 Ohm, 5W
Resistor, 150Ohm, 1/2W,5%
Resistor. 453 Ohm. 1/4W.
1%
3
4
1
~
Table 2-1. Test Panel Parts List
2-2 190-00149-02 Rev B
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HEADSET
PILOT
@
@
COPILOT
PASS
150 OHM
@
@
69
OFF
LOAD
150 OHM
OFF
LOAD
150 OHM
OFF
LOAD
8 OHM
EXT SPKR
LOAD
J1 PIN 9
6)
(3
@
J1 PIN24
J1 PIN33
J1 PIN38
MICROPHONE
@
PILOT
COP1LOT
PASS1
PASS3
ON
@ OFF
@ OFF
@
@
PTT
ON
PTT
PASS2
PASS4
@@
MUSlCl MUSIC2
IN IN
TEST POINTS
@@@
J1 PIN 10 J1 PIN 11 J1 PIN 12
J1 PIN 25 J1 PIN 26 J1 PIN27
J1 PIN 34
J1 PIN 35 J1 PIN 36
@@a
J1 PIN 39 J2 PIN 16 J2 PIN 31
J1 PIN23
@
@
(3
J1 PIN 28
J1 PIN37
ACFT GND
COM3 MIC COMI KEY
COMI MIC COM3 KEY
COM2 KEY
COM2 MIC
PA MUTE
MIDDLE MKR
SENSE
EXT SPKR
PASS HS R
PASS HS L
COP HS R
COP HS L
PIL
HS R
HS @
OUTPUTS
MUSlCl L MUSlCl R
TEL RING MUSIC2 L
ALT WARN MUSIC2 R
PIL MIC
COP MIC
PASS1 MIC
NAV2
PASS2 MIC
NAV’ PASS3 MIC
COM3 PASS4 MIC
COM2
COMI
(@ ‘5 LOADMIC
WIPE
0
0
ACFT
PWR
ACFT
GND
INPUTS
ON ON
OFF OFF
SWAP TONE MASQ
ENABLE INHIBIT
PWR
0 LGT
GND
28V
14V
TP
GND
ACFT
LGT
OFF
ON
@ OFF
ICS MUTE
INHIBIT
MKR ANT
IN
Figure 2-2. Typical Test Panel Layout
190-00149-02 Rev B 2-3
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1.
Proper insulation and grounding ofjacks, plugs, switches, and shielded wires is required to avoidaudio
signal ground loops.
2.
To ensure proper shieldingand grounding, the test panel should be housed in a conductive metal enclosure.
It is critical that all hardware be electrically isolated from the test panel chassis to avoid audio ground loops.
3. Unless otherwise noted, all wires used in the test panel are 24 AWG.
4. Aircraft power leads should be as short as possible and routed near the test panel faceplate. Use 22 AWG
wire for the connections from 52 pins
8 through 11to the test panel ACFT PWR and ACFT GND banana
jacks.
5. Use a minimal length of RG-188A coax cable or equivalent from the test panel MKR IN connector to 51
pins 1and 2.
6.
All two and three conductor shieldedwires must have shields terminated at one end only. The other end
must be left floating from ground.
7.
Shielded wires for the harness from the test panel to the unit under test should be terminated to the
respective
J1 and 52 connector backshells.
8.
Use Belden wire #83318and #83333 or equivalent for two and three conductor shielded pairs respectively.
9. Both rotary switches have a dedicated BNC connector for convenient connection to the test equipment.
Deck “A” common of each rotary switch is wired to the appropriate BNC center conductor. Deck
“B”
common of each rotary switch is wired to the appropriate BNC outer conductor.
10. The TP GNDjack is the single point ground connection between the test panel and the power supply.
Shielded wires within the test panel may terminate to any point on the test panel chassis.
1 1. The wiring harness from the test panel to the unit under test should be as short as possible for convenient
testing of the GMA 340.
12. Test panel labeling may be altered to accommodate the GMA 340 Dual ADF. Regardless of labeling, all
functions will be tested on all versions of the unit.
2.4 TEST HARNESS, J1 AND 52 PIN ASSIGNMENTS
The following table provides pin assignment information for connectors J 1and 52 test harness construction. The
test harness, an integral part of the test panel, is similar to connections in an aircraft.
2-4 190-00 149-02 Rev B
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Pin # 11 Connector J1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
Mkr Ant
Mkr Ant Gnd
Corn
3 In
Corn
3 Gnd
Corn
3 Mic
Corn
3 Key
ADF In (ADF
2 In)
ADF Gnd (ADF
2 Gnd)
Corn
1 In
Corn
1 Gnd
Corn
1 Mic
Corn
1 Key
Corn
2 In
Corn
2 Gnd
Corn
2 Mic
MASQ Inh
Nav
1 In
Nav
1 Gnd
Nav
2 In
Nav 2 Gnd
DME In (ADF
1 In)
DME Gnd(ADF
1 Gnd)
Corn
3 Spkr Load
Corn
3 Spkr Load Gnd
Corn
1 SpkrLoad
Corn
1 Spkr Load Gnd
Corn
2 Spkr Load
Corn
2 Spkr Load Gnd
NC
Corn
2 Key
Pilot Headset R
Alt Wrn Gnd
Pilot Mic In
Pilot Mic Key
Pilot Mic Gnd
Ext White Lamp; A
Ext Blue Lamp;
0
Ext Amber Lamp; M
Middle Mkr Sens
Pass Headset L
Pass Headset R
Pass Headset Gnd
Tel Ringer Gnd
Tel Ringer In
Connector52
Pilot Headset Gnd
CO-PilotHeadset Gnd
CO-PilotHeadset L
CO-Pilot Headset R
14V Lgt LoI28V Lgt Lo
14VLgtl28V Lgt Lo
14VLgtf28V Lgt
Aircraft Power
Aircraft Power
Aircraft Ground
Aircraft Ground
PA Mute
ICS Mute Inhibit
ICS Mute Inhibit Return
NC
Pilot Headset L
8 Ohm Select
Reserved
Tone Enable
Swap
Swap Return
NC
Music
1 L In
Music
1 RIn
Music
1 Gnd
Music
2 L In (NC)
Music
2 R In (DME In)
Music
2 Gnd (DME Gnd)
NC
Corn
TX Mute
Pilot Headset
R
CO-PilotMic In
CO-PilotMic Key
CO-PilotMic Gnd
Pass
1 Mic
Pass
1 Mic Gnd
Pass
2 Mic
Pass
2 Mic Gnd
Pass
3 Mic
Pass
3 Mic Gnd
Pass
4 Mic
Pass
4 Mic Gnd
SpkrGnd
Spkr Out
Table 2-2. J1 and 52 Pin Assignments (Dual ADF in Parentheses)
190-00149-02 Rev B 2-5
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311
1
MKR
ANT IN
ADF In (ADF 2 In)
w ,I
DME In (ADF 1 In)
TIP
@jK
JZ
1
14VLgt L0/2BV Lgt Lo
14VLgff28VLgt Lo
ACFT
PWR
ACFT
GND
ICS Mute Inhibit
ICS Mute InhibitReturn
Music2
R (DME In)
Music 2 Gnd (DME Gnd)
Pass 1 Mic Gnd
Pass2 Mic Gnd
Pass 3 Mic Gnd
Pass4 Mic Gnd
Figure 2-3. Test Panel Schematic Diagram (Dual ADF in Parentheses) (Sheet 1 of 4)
2-6 190-00 149-02 Rev B
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HEADSET
LOADSWITCHES
U /\ A E-
Pilot HS R
I-
f*{ -
Pass bund
I
PassHS L
E-
Pass HS R
UA Pass 1 Mic
PASS 1
MIC
Pass 3 Mic Gnd
Pass 3 Mic
PASS 3
MIC
PILOT PlT
Iv
PilotMlc Gnd
PilotMic In
Pilot Mic Kev
PIL T
MI8
COPILOT PTT
I----
lb_ Cop Mic Gnd
Cop Mic In
Cop Mic Key
COPILOT
MIC
ACFT LGT
SELECT
14VLgt LoI28V LgtLo
d-\
14VLgtl28VLgtLo
14v
14VLgtl28V Lgt LGT
Music2 Gnd
s
Music2 L
Music2 R
MUSIC 2
IN
Pass2 Mic
g$gs 2
Pass4 Mic Gnd
Music1 Gnd
A Pass4 Mic A Music1R
PASS 4 MUSIC 1
MIC IN
Figure 2-3. Test Panel Schematic Diagram (Sheet 2)
190-00149-02 Rev B 2-1
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,Corn 3 Mic
,Corn
2 Mic
,Corn
1 Mic
I
1-
Middle MkfSens@
flu&
Spkr Gnd 0
A
0-NC
0-NC
-NC
ACFT GND
TP
GND
SWAP
Swap oio SwapReturg
ICS MUTE
INHIBIT
0
ICSMute Inhibit
ICS Mute Inhibit Return
NOTE: All loadsare QW/5% unlessotherwisenoted.
-
ACFT-GND
TP CHASSIS
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Music 1 L
Tel Ring In
Pb ADF lin
< 0
DME In
0
0
Nav 2 In
NavlIn
0
n
h
Corn 3 In
7,
Corn 2 In
Corn
1 In /
WIPE
* o---
Wipe
TONE
ENABLE
Tone Enable
MASQ
INHIBIT
0
MASQ Inh
b
I
-I
- -
ACFT GND
Music 1R Music
1 Gnd
-
l-9
L"
I
Music 2 L
-
e
Music 2 R
Tel RingGnd
At Wam Gnd
b
PilotMic In ADF Gnd
DME Gnd
Nav
2 Gnd
Cop Mic In
-
Pass 1 Mic
Pass
4 Mic
MICLOAD
EXT MKR
LAMP
LOADS
56 OHM/5W (X3)
Ext Mkr Lamp
1
ACFTGND
PilotMicGnd
Cop MicGnd
Pass
1 MicGnd
0
Pass 2 MicGnd
Pass
3 MicGnd
Pass4MicGnd
'NC
EXT SPKR
LOAD
24 OHMllOW (x6)
KzzL
I I
I
- U
Spkr Gnd
9"
8 Ohm Sel
-
ACFTGND
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( '-.
C (7AX CALiLE
Notes:
1. Prepare 12" long piece of coax cable as shown.
2. Prepare 5" long piece of coax cable as shown and splice into 12" long piece by wrapping inner conductor of
5" piece around braided shield of 12" piece and soldering in place.
3. Install heat shrink tubing over spliced area sufficient to completely insulate splice. Shrinkto fit.
4. Terminate all 3 ends with typical BNC connectors as shown in example.
Figure 2-4. Audio Coax Cable Assembly
2-10 190-00149-02 Rev B
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SECTION 3
TROUBLESHOOTING
Individual components and assemblies in the GMA 340 Audio Panel can be
damaged by ESD (Electrostatic Discharge). Observe proper ESD procedures
when troubleshooting the unit.
3.1 TROUBLESHOOTING
This section contains information to aid in troubleshooting the GMA 340 to the replaceable assembly level. In
general, entry into the troubleshooting section occurs after
a failure in the testing section. The type of failure
found in the test procedure determines the correct troubleshooting procedure. After the faulty module
is isolated
and repair is made, the unit should be retested using the functional test procedure in Section
5, TESTING of this
manual to ensure that the repaired area is operating correctly and that other areas have not been damaged during
the repair procedure.
3.2 TROUBLESHOOTING PROCEDURES
This troubleshooting guide is designed to allow isolation of malfunctions to the power input board or the front
panel subassembly. These checks reference specific tests in Section
5, TESTING of this document. Referring to
the disassembly section, remove the top and bottom covers to perform the checks in the following paragraphs.
For tests not covered in this section, the entire unit must be returned to the factory for repair and return to service.
Figures 3.1, 3.2 and 3.3 are provided for connector location, pin numbering orientation and pin function.
190-00 149-02 Rev B
3- I
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no 0
0
0
=:O 0
000
00
ono
00
000 =:
00
0000
Figure 3.1. Front Panel Rear View, Connector J1 and 52 Location
Front Panel
Pin
1=:-1
I Pilot II J1 Pin 22 I
I CREW II J1 Pin 23 I
I TEST II J1 Pin 18 I
Table 3.1. Front Panel Connector Detail (Dual ADF in Parentheses)
3-2 190-00149-02 Rev B
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