LG 49SK8000PUA Service Manual page 39

Standard Repair Process
Error
symptom
* Please refer to the all cases which can be displayed on power off mode.
Power Off list
Power off when TV is not turned off during a certain time
KEYTIMEOUT RESULT : micom force to trigger TV power off.
CONDITION : When pressing power key while power on/off status, CPU does not response within 8 seconds
Almost the same as Power Off by KEYTIMEOUT. If there is no vaild communication
Bet ween CPU and MICOM for more than 5 seconds, the MICOM switcheds off PSU and
1SEC Power OFF
Records. Power off by 1SEC Power off. In this case, we don't have information where the
malfunction exactly occurred. But in in indicates that CPU had stopped and rebooted.
In case of AC Off (It is normal when the power cord is unplugged.)
ACDET
If there are many ACDETs connected, Power Board is defective
Power off by unstable AC power detect.
RESULT : micom check the stable power.
5V MNT
CONDITION : When AC on or DC on, stabilization check routine (Power Detect High
Check) fail after multi power on.
CPUABNORMAL If the CPU attempts to reset in case of abnormal operation and Shut Down in case of failure.
Power off when receiving no ack.
NO POLING RESULT : TV power off/on (Reboot)
CONDITION : There is no I2C response from CPU for 15 seconds.
Power off by main SoC command.
CPUCMD
Power off by module error (OLED)
INV_ERROR
CONDITION : OLED Module send signal to micom
ONRF_FAIL RESULT : Reboot,
PNWASHFAIL Power off by panel noise wash function fail case.
RESET When Micom is reset by AC Off
KEY Power off by Local key
OFFTIMER Power off by Off timer
SLEEPTIMER Power off by sleep timer
NOSIG Power off by No Signal
FANSTOP Power off by FAN operation stopped
INSTOP Power off by Instop Key
AUTO OFF Power off by auto off function
RESREC Power off by reserved recording
RECEND Power off when recording stops
SWDOWN Reboot by SW down load function
UNKNOWN
No meaning (same as initial value)
COMP_END OLED threshold voltage degradation(Compensation) completes.
PNWASHDONE Power off by panel noise wash function complited. (OLED)
B. Power error
Off when on, off while viewing, power auto on/off
Explanation
CONDITION : OLED module compensation is running but fails.
Established
date
Revised date
8
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Action contents
Check & Change Main B/D
Check & Change Main B/D
Normal
Check & Change Power B/D
Check & Change Power B/D
Check & Change Main B/D
Check & Change Main B/D
Check & Change Main B/D
Check & Change OLED Module
Check & Change OLED Module
Check & Change OLED Module
Normal Case