LG OK99 User manual

SERVICE MANUAL
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS”
IN THIS MANUAL.
CONFIDENTIAL
MODEL: OK99
P/NO : AFN78511848 SEPTEMBER, 2018
MODEL: OK99
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
HI-FI SYSTEM

CONTENTS
SECTION 1 ........ GENERAL
SECTION 2 ........ CABINET & MAIN CHASSIS
SECTION 3 ........ ELECTRICAL
SECTION 4 ........ MECHANISM (DM19D)
1-1
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.

SECTION 1
SUMMARY
CONTENTS
SERVICING PRECAUTIONS ............................................................................................................................ 1-3
ESD PRECAUTIONS......................................................................................................................................... 1-5
HIDDEN KEY MODE ......................................................................................................................................... 1-6
1. HIDDEN KEY MODE TABLE
2. HIDDEN KEY MODE DESCRIPTION
PROGRAM DOWNLOAD GUIDE...................................................................................................................... 1-7
FOTA UPDATE STEP USING BT APP .......................................................................................................... 1-10
SPECIFICATIONS ........................................................................................................................................... 1-12
1-2
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.

1-3
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
NOTES REGARDING HANDLING OF THE PICK-UP
1. Notes for transport and storage
1) The pick-up should always be left in its conductive bag until immediately prior to use.
2) The pick-up should never be subjected to external pressure or impact.
2. Repair notes
1) The pick-up incorporates a strong magnet, and so should never be brought close to magnetic materials.
2) The pick-up should always be handled correctly and carefully, taking care to avoid external pressure and
impact. If it is subjected to strong pressure or impact, the result may be an operational malfunction and/or
damage to the printed-circuit board.
3) Each and every pick-up is already individually adjusted to a high degree of precision, and for that reason
the adjustment point and installation screws should absolutely never be touched.
4) Laser beams may damage the eyes!
Absolutely never permit laser beams to enter the eyes!
Also NEVER switch ON the power to the laser output part (lens, etc.) of the pick-up if it is damaged.
5) Cleaning the lens surface
If there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as used
for camera lens). The lens is held by a delicate spring. When cleaning the lens surface, therefore, a cot-
ton swab should be used, taking care not to distort lens.
6) Never attempt to disassemble the pick-up.
Spring has excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab.
(Do not use any other liquid cleaners, because they will damage the lens.) Take care not to use too much
of this alcohol on the swab, and do not allow the alcohol to get inside the pick-up.
Storage in conductive bag Drop impact
NEVER look directly at the laser beam, and don’t allow
contact with fingers or other exposed skin.
Magnet
How to hold the pick-up
Conductive Sheet
Cotton swab
Pressure
Pressure
SERVICING PRECAUTIONS

NOTES REGARDING COMPACT DISC PLAYER REPAIRS
1. Preparations
1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode). These components
are sensitive to, and easily affected by, static electricity. If such static electricity is high voltage, components
can be damaged, and for that reason components should be handled with care.
2) The pick-up is composed of many optical components and other high-precision components. Care must be
taken, therefore, to avoid repair or storage where the temperature or humidity is high, where strong magne-
tism is present, or where there is excessive dust.
2. Notes for repair
1) Before replacing a component part, first disconnect the power supply lead wire from the unit
2) All equipment, measuring instruments and tools must be grounded.
3) The workbench should be covered with a conductive sheet and grounded.
When removing the laser pick-up from its conductive bag, do not place the pick-up on the bag. (This is
because there is the possibility of damage by static electricity.)
4) To prevent AC leakage, the metal part of the soldering iron should be grounded.
5) Workers should be grounded by an armband (1 M)
6) Care should be taken not to permit the laser pick-up to come in contact with clothing, in order to prevent
static electricity changes in the clothing to escape from the armband.
7) The laser beam from the pick-up should NEVER be directly facing the eyes or bare skin.
Resistor
(1 M)Conductive
Sheet
Resistor
(1 M)
Armband
1-4
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.

1-5
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components
commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated
circuits and some field-effect transistors and semiconductor chip components. The following techniques should
be used to help reduce the incidence of component damage caused by static electricity.
1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off
any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a
commercially available discharging wrist strap device, which should be removed for potential shock reasons
prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ESD devices, place the assembly on a conductive surface
such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ESD devices.
4. Use only an anti-static solder removal device. Some solder removal devices not classified as "anti-static" can
generate electrical charges sufficient to damage ESD devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD
devices.
6. Do not remove a replacement ESD device from its protective package until immediately before you are
ready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by
conductive foam, aluminum foil or comparable conductive materials).
7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the
protective material to the chassis or circuit assembly into which the device will by installed.
CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER
SAFETY PRECAUTIONS.
8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion
such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate
static electricity sufficient to damage an ESD device).
CAUTION. GRAPHIC SYMBOLS
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS
INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED
“DANGEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF
ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE
SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE
LITERATURE.
ESD PRECAUTIONS

1-6
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
HIDDEN MODE ENTRANCE KEY(Audio) EXIT KEY
Version Check Front ‘Stop’ 
+ Remote Control Key ‘Play’ for 5s Remote Control Key ‘Play’ for 1.5s
EEPROM INITIAL Front ‘Stop’ 
+ Remote Control Key ‘ ‘ for 5s Auto exit
1. HIDDEN KEY MODE TABLE
HIDDEN KEY MODE
//
2. HIDDEN KEY MODE DESCRIPTION
2-1. Version Check
- Function : Version Check.
- Entrance Key : Front ‘Stop’ + Remote Control Key ‘Play’ for 5s.
- Exit Key : Remote Control Key ‘Play’ for 1.5s.
- Operation explanation : Remote Control Key OR .
VFD Display (Example) Result
MCS Version
MICOM Version
OPTION Version
DEMO Version
DJ PRO Version
EQ Version
EQ Check sum Version
2-2. EEPROM Initial
- Function : Initialize data stored in EEPROM and BACKUP RAM data.
- Entrance Key : Front ‘Stop’ + Remote Control Key ‘ ‘ for 5s.
- Exit Key : Auto exit.
- Explanation : ‘E2P CLR’ is displayed on the VPD and turn off the power automatically.

1. AUDIO PROGRAM
Download program file name must be MICOM_OK99_YYMMDDX.HEX
If security program(Water Wall) is activated on PC, you must save the file to the USB storage device
and disable the security software, then download the file to your set.
Downloading file proceeds in the same way at USB1 function and USB2 function.
Caution: When downloading the file, you should neither unplug the USB device, change to the other function,
nor power off the device. USB device must be unplugged when the downloading process is completed.
ON VFD DISPLAY SCREEN
1) (Fast) Format USB device.
2) Copy Firmware file to USB device.
NO USB
Insert USB device at USB function.
SEARCH

MICOM UP

FINISH

AUTO POWER OFF
1-7
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
PROGRAM DOWNLOAD GUIDE

2. CD PROGRAM
Download program file name must be HG790_OK99_YYMMDDX.bin
If security program(Water Wall) is activated on PC, you must save the file to the USB storage device
and disable the security software, then download the file to your set.
Downloading file proceeds in the same way at USB1 function and USB2 function.
Caution: When downloading the file, you should neither unplug the USB device, change to the other function,
nor power off the device. USB device must be unplugged when the downloading process is completed.
ON VFD DISPLAY SCREEN
1) (Fast) Format USB device.
2) Copy Firmware file to USB device.
NO USB
Insert USB device at USB function.
SEARCH

FIRMWARE

FINISH

AUTO POWER OFF
1-8
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.

3. EQ & DEMO PROGRAM
Download program file name must be EQ_DEMO_PRG_OK99_XXXX.BIN
If security program(Water Wall) is activated on PC, you must save the file to the USB storage device
and disable the security software, then download the file to your set.
Downloading file proceeds in the same way at USB1 function and USB2 function.
Caution: When downloading the file, you should neither unplug the USB device, change to the other function,
nor power off the device. USB device must be unplugged when the downloading process is completed.
ON VFD DISPLAY SCREEN
1) (Fast) Format USB device.
2) Copy Firmware file to USB device.
NO USB
Insert USB device at USB function.
SEARCH

EQDEMOUP

FINISH

AUTO POWER OFF
1-9
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.

1-10
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
FOTA UPDATE STEP USING BT APP
Step1 : App connecting
(Check FW version)
After connecting the BT App with SET,
the user could find the “Device Version info” on
Setting tab.
Step3 : Select update button
When touch the “Update” button, user could
update the SET firmware using FOTA.
Step2 : Device version info
When touch the “Device Version info” button,
user could find the current and latest SET
version on pop-up menu.
Step4 : Confirm update
Select the OK button on the caution message.

1-11
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Step5 : Download from CDN server
1st step is download from CDN server to
smart phone. The progress bar is displayed
on BT App.
Step7 : FW Flash Writing Step8 : FOTA complete
After completed the download from the smart
phone, the SET overwrite the firmware to flash
memory.
When finishing the flash memory writing, pop-up
message about finish is displayed and the SET
auto power off.
Step6 : Transfer FW
After completed the download from server,
smart phone start to transfer the firmware to the
SET. The progress bar is displayed on BT App.

SPECIFICATIONS
1-12
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
GENERAL
Power requirements Refer to the main label on the unit.
Power consumption Refer to the main label on the unit.
Dimensions (W x H x D) Approx. 430 mm x 1,050 mm x 400 mm
Operating temperature 5 °C to 35 °C
Operating humidity 60 %
INPUTS
Digital audio in (OPTICAL IN) 3.3 V (p-p), Optical jack x 1
Analog audio in (AUX IN) 2.0 Vrms (1 kHz, 0 dB), 600 Ω, RCA jack (L, R)
Portable in (PORT. IN) 1.0 Vrms (3.5 mm stereo jack) x 1
Microphone (MIC 1/2) Sensitivity 20 mV (1 kHz), 6.3 mm jack x 2
TUNER
FM Tuning Range 87.5 to 108.0 MHz or 87.50 to 108.00 MHz
SYSTEM
Frequency Response 40 to 20,000 Hz
Signal-to-noise ratio More than 75 dB
Dynamic range More than 80 dB
Bus Power Supply (USB) 5 V 500 mA
Available Digital Input Audio Sampling Frequency 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz
AMPLIFIER (RMS Output power)
Total output 1,800 W RMS
HIGH 450 W RMS × 2 (6 Ωat 1kHz, 15% THD)
LOW 900 W RMS (12 Ωat 200Hz, 15% THD)
Design and specifications are subject to change without notice.

SECTION 2
CABINET & MAIN CHASSIS
CONTENTS
DISASSEMBLY INSTRUCTIONS ..................................................................................................................... 2-2
EXPLODED VIEWS ........................................................................................................................................... 2-9
1. CABINET AND MAIN FRAME SECTION ................................................................................................. 2-9
2. DECK MECHANISM SECTION .............................................................................................................. 2-11
3. PACKING ACCESSORY SECTION ....................................................................................................... 2-13
2-1
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.

2-2
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
DISASSEMBLY INSTRUCTIONS
Figure 1. Panel Side L/R disassembly - 1
Figure 2. Panel Side L/R disassembly - 2
1) Remove the 6 screws.
2) Disassemble each of the two screws located inside the handle.

2-3
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 3. Panel Side L/R disassembly - 3
Figure 4. Panel Top disassembly - 1
3) Pull out Cover Side Assembly L/R in the backward direction.
4) Remove the 3 screws.

2-4
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 5. Panel Top disassembly - 2
Figure 6. Panel Top disassembly - 3
5) Remove the two screws on the left and right sides.
6) As shown in the figure, remove the Panel Top by pushing the front part and lifting the rear part.

2-5
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 7. Panel Rear disassembly
7) Remove the 9 screws on the Panel Rear.
Figure 8. Main Set disassembly - 1
8) Bracket MD + Frame Main Screw 4 EA Disassembly

2-6
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 10. Main Set disassembly - 3
10) Power Cable Disconnection
Figure 9. Main Set disassembly - 2
9) Remove the Set LED Connector / Speaker LED Connector / Speaker Network cable.

2-7
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 11. Main Set disassembly - 4
11) Grasp both sides and pull upward to remove the assembly.
12) Complete removal of the Main Set.
Figure 12. After detaching the Main Set