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PWB QUICK CHECK:
Look for any burns, open fuses, etc...
If burns found, then replace the PWB.
If fuses open, first check for low ohms condition before replacing the fuse an attempting to turn on the set.
VOLTAGE CHECKS:
(When AC applied, then when the Power Button is pressed)
WHEN AC FIRST APPLIED:
When AC is first applied, the power supply should turn on and supply the
following voltages for a little more than 2 minutes.
•
Stand-By voltages (SBY 5V), (SYB 3.3V on some models) and all voltages on the CNPPS connec-
tor? (This requires Power 1 and Power 2 commands being high coming from the Digi-Main PWB
CN63). After approx. 2 minutes, (unless Quick Start is on), a relay click is heard and the CNPPS
voltages turn off.
If Quick Start is on, the Power 1 and 2 commands remain high and all above voltages remain on.
WHEN THE POWER BUTTON IS PRESSED:
When the power button is pressed, the Logic PWB sends
Vsago and Vcego commands to the power supply via the CN64 connector.
•
Note: There are two conditions the set can be in before the power button is pressed.
1. If Quick Start is off, the Power 1 and Power 2 commands are output from the Digi-Main PWB
after a short internal self diagnostics is run.
2. If Quick Start is on, the above does not happen because the Power 1 and 2 commands are
already high as stated in “When AC is First Applied”.
Are you generating the Vs and Va voltages. (This requires the Vcego and Vsago commands being high coming
from the Logic PWB CN68 connector).
42"
Va CN64 pin 1
Vs (85V) CN64 pin 7.
-Vs (-85.5) CN64 pin 9. (New for the DW-3 Chassis)
50"
Va (60V) CN64 pin 1
Vs (80V) CN64 pins 8 or 9 or 10.
Note: There is a great deal of information on our web site about how to Force the Power Supply to produce
all of the above voltages to check the Power Supply PWB and how this Power Supply generates voltages.
(See this models Things You Should Know section Power Supply Issues for information.)
http://www.hitachiserviceusa.com/service/Seminars/Plasma-Web/DW3-Web/Fixes/00-Things-Known.htm
IMPORTANT NOTE: FOR CONDITIONS 2 and 3 BELOW IN THE DW-3 SERIES:
Any Time Vs/Va voltages do not appear and a test is made, each time a new test is to be made,
•
Press the Power Button and Turn the Plasma OFF.
•
Wait until you hear a "Click".
•
Unplug the CN68 connector.
•
Re-Plug the CN68 connector.
If this is not done, the Turn On command for Vs/Va at Pin 7 and 8 of
the CN68 connector will not happen.
•
Additional Note: If the Connector CN-68 is pulled and voltage readings are taken on the CN68
connector at the Power Supply, the STB 3.3V will be present at pin 3. There will be no voltage at
pin 1.
This answer to Are you Generating Vs and Va voltages will be;
1) Yes (Green Power LED will be always on)
2) Brief rise the collapse (Green Power LED will go Green then Go Off or may stay Green)
3) No (Green Power LED will go Green then Go Off or may not go Green at all)
There are three possible answers, see next page for Troubleshooting based on your response:
DW-3 NO PICTURE TROUBLESHOOTING Page 2 of 10
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