LG 42LY770M, Service Manual

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- 18 - LGE Internal Use Only Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
7. AUDIO output check
7.1. Audio input condition
(1) RF input: Mono, 1KHz sine wave signal, 100% Modulation
(2) CVBS, Component: 1KHz sine wave signal (0.4Vrms)
7.2. Specification
8. GND and HI-POT Test
8.1. GND & HI-POT auto-check preparation
(1) Check the POWER CABLE and SIGNAL CABE insertion
condition
8.2 GND & HI-POT auto-check
(1) Pallet moves in the station. (POWER CORD / AV CORD is
tightly inserted)
(2) Connect the AV JACK Tester.
(3) Controller (GWS103-4) on.
(4) GND Test (Auto)
- If Test is failed, Buzzer operates.
- If Test is passed, execute next process (Hi-pot test).
(Remove A/V CORD from A/V JACK BOX)
(5) HI-POT test (Auto)
- If Test is failed, Buzzer operates.
- If Test is passed, GOOD Lamp on and move to next
process automatically.
8.2.1. Checkpoint
▪ TEST voltage
- GND: 1.5 KV / min at 100 mA
- SIGNAL: 3 KV / min at 100 mA
▪ TEST time: 1 second
▪ TEST POINT
- GND TEST = POWER CORD GND & SIGNAL CABLE
METAL GND
- Hi-pot TEST = POWER CORD GND & LIVE & NEUTRAL
▪ LEAKAGE CURRENT: At 0.5 mArms
9. USB S/W Download(Service only)
(1) Put the USB Stick to the USB socket
(2) Automatically detecting update file in USB Stick
- If your downloaded program version in USB Stick is
Lower, it didn’t work.
But your downloaded version is Higher, USB data is
automatically detecting (Download Version High & Power
only mode, Set is automatically Download)
(3) Show the message “Copying files from memory”
(4) Updating is starting.
(5) Updating Completed, the TV will restart automatically.
(6) If your TV is turned on, check your updated version and
Tool option. (explain the Tool option, next stage)
* If downloading version is more high than your TV have,
TV can lost all channel data. In this case, you have to
channel recover. if all channel data is cleared, you didn’t
have a DTV/ATV test on production line.
* After downloading, have to adjust Tool Option again.
(1) Push "IN-START" key in service remote control.
(2) Select "Tool Option 1" and push "OK" key.
(3) Punch in the number. (Each model has their number)
Item Audio practical max Output, L/R
Min
9.0
8.5
Typ
10.0
8.9
Max
12.0
9.9
Unit
W
Vrms
Remark
(1) Measurement condition
- EQ/AVL/Clear Voice: Off
(2) Speaker (8Ω Impedance)