HOW TO DO A HARD RESET – FAULTS AND REMEDIES - PANASONIC PLASMA TVs
TH65PZ850U, TH58PZ850U, TH50PZ850U, TH46PZ850U, TH58PZ800U,
TH50PZ800U, TH46PZ800U, TH42PZ800U, TH50PZ80U, TH46PZ80U, TH42PZ80U, TH50PX80U, TH42PX80U, TH50PZ85U, TH46PZ85U, TH42PZ85U.
How to perform a hard reset to Panasonic Plasma TV
Normally; a hard reset can be done by unplugging the
TV from AC mains wall socket, and re-plug it back after some minutes or hours.
To
perform HARD RESET of Plasma TV unit by pressing & holding VOL DOWN
(-) on unit and MENU button on remote at the same time for about 3 seconds. This must be done if you replace the main
board of the TV. All new A boards
supplied from factory needs to be initialized.
After the main board replacement. once
AC power cord is plugged in, unit will turn on by itself. Depends on factory
settings, unit will either display Video, Component or Tuner icon. After few seconds, screen will change
to service mode automatically. NOTE: Since unit is in service mode,
only buttons 1, 2, 3 or 4 on remote are working (rest of buttons are
nonfunctional). After hard reset, confirm if Plasma TV powers ON in user mode and check overall functionality.
FAULTS TO 46" PLASMA TVs
* The
unit shuts down and power LED blinks 10 times.
> Shorted
Q409 & open PR401. Replace Q409
& PR401
Speaker
box is making rattling sound; contact
with cabinet parts
* Vibration
noise from left or right speaker.
Speaker box is making direct contact with cabinet parts.
> Installing
mounting screw in the center of speaker box prevents from touching the cabinet
parts and minimizes the risk of vibration noise. Install screw, part number THEL049 to both
speaker boxes as shown here. Repeat the
same for left speaker box.
Relay
clicks then TV shuts down with power LED 10 blinks
* When
AC cord plugged in, relay clicks then TV shuts down with power LED 10 blinks.
> No
Vin supply to IC520 (power control IC) due to open R712 & shorted C527.
Replace
R712 & C527
R712: ERJ6GEYJ4R7
C527: ECJ3YB1E475K
Picture disappears after a few minutes, but sound is
OK.
* Low
Ldo_5V supply to IC9800 (DC to DC Converter) due to leaky D9801.
> Replace D9801 on the D board.
D9801:
B0JCDD000002
Shuts
down with power LED 10 blinks.
* Missing
395Vdc output due to shorted Q412 & Q413 and open PR401.
> Replace
Q412, Q413, PR401 & check/replace Q408 and Q409. Note: Always confirm condition of Q408 &
Q409, in some cases could be shorted.
Q412 & Q413: B1DEGQ000070
Q408 & Q409:
B1DHCD000034
PR401: K5Y502BA0001
