TROUBLESHOOTING USING LED & OSD
LAMP STATE
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POWER SUPPLY STATE
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REMEDY
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Not lighted
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Power supply circuit faulty.
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Replace Power Supply PCB # {Vs & Vd must be adjusted}
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Blinks RED [continiously]
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Power turned off immediately.
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Check-1 [stated below]
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Blink once RED.
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Power turns off after 10 seconds.
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Check 2 [stated below]
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Blinks twice RED.
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Power turned off after 10 seconds
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Check 3 [stated below]
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Blinks four times RED.
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Power not turned off, LED blinks only
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Replace Main/Digital PCB assy.
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Blinks five times RED.
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Power not turned off, LED blinks only.
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Replace Video PCB Assy.
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LED lights steady for more than 10 seconds [GREEN]
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Is on screen display normal? If NO:
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PDP panel faulty
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Replace PDP panel
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Is on screen display normal? If YES
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All input image faulty.
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Signal processing PCB faulty.
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Replace Main/Digital PCB assy.
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Video input image faulty.
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Video PCB faulty.
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Replace Video PCB Assy.
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s-video input image faulty.
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Video PCB faulty.
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Replace Video PCB Assy.
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Component video input image faulty.
RGB 1,2, input image faulty.
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Signal processing PCB faulty.
Check 4 |
Replace Main/Digital PCB Assy.
Stated below.
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CHECK-1
START >>
[Power supply protector operated.
Power Lamp Flashing continuously in RED; at an interval of (0.5) sec.]
- Turn the main power off and disconnect the connector P2,P3,P4 & P6 on the Main Power PCB.
- Connect pin [1] and pin [13] of (P2) through a [1/4W, 1Kohms] resistor.
- Turn the main power ON again.
- Measure during telay turning On and OFF.
Is voltage at connector [P5] pin 10(Vs) 160V and pin 7(VD)
65V on main power board? If YES, PDP
panel is faulty. Repalce it. [*Vs &
Vd must be adjusted after replacement]
CHECK 2
Start >> Power lamp flashes once intermittently in
RED; for (0.5) second, at an interval of 3 seconds.
Start:
Is voltage at connectors [P951-3 pin; P953-3 pin and P954-3
pin] on Main/digital PCB 14V?
If NO; Microcomputer peripheral circuit faulty.
Replace Main/Digital PCB Assy.
If YES; fan faulty.
Replace fan.
CHECK 3
Temperature protector operated. Power Lamp flashes intermittently twice in RED; for (0.5) sec. At
an interval of 5 seconds.
Start >>
Is ambient temperature of IC747 on Main/Digital PCB less than 60 degree centigrade? If NO: adjust
PDP unit installation so that perefearal temperature is 40 Degree Centigrade or
less.
Does the unit operate normally when temperature sensor IC757
changed?
If No: microcomputer
perifearal circuit faulty. Replace
Main/Digital PCB Assy.
If YES: temperature
sensor IC757 faulty. Replace
temperature sensor IC757.
[The temperature sensor IC is installed on Main/digital
PCB. Turn OFF power and cool with a
point cooler]
CHECK 4
RGB input is abnormal.
The power lamp lighted green for 10 seconds or more.
Start>>
- Is RGB cable pin arrangement appropriate? Inf NO, check connection cable.
- If RGB cable pin arrangement is appropriate? If YES
- What kind of signal is output from signal source?
- Separate signal. Is horizontal sync. Sgnal input tp pin 13 and vertical sync signal input to pin 14 of RGB cable is OK?
- If not, check input signal. If Yes, ronnect the RGB cable to terminal. Is sync. Switch (TLL/ANALOG) selected correctly?
- If YES; check Sync signal polarity is negative. If YES;
- Is frequency of horizontal sync and vertical sync signals within specified range? If no, check input signal. If yes, check whether the input level is within specified range. If it also is okey, Signal processing circuit is faulty. Repalce Main/digital PCB Assy.
- Come to [3] of above. Composite signal.
- Is composite sync. Signal input to pin13 of RGB cable? If YES; go to step-5 above and proceed. If NO, check input signal.