Sanyo LCD-42XR7H, Service Manual

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35
Trouble shooting
Before servicing please check to find the possible causes of the troubles according to the table
below.
1.Antenna(signal):
Picture is out of focus or jumping Bad status in signal receiving
Poor signal
Check if there are failures with the electrical connector or
the antenna.
Check if the antenna is properly connected.
Fringe in picture Check if the antenna is correctly oriented.
Maybe there is electric wave reflected from hilltop or
building.
Picture is interfered by stripe
shaped bright spots Possibly due to interference from automobile, train, high
voltage transmission line, neon lamp etc.
Maybe there is interference between antenna and power
supply line. Please try to separate them in a longer
distance.
Maybe the shielded-layer of signal wire is not connected
properly to the connector.
There appear streaks or light color
on the screen Check if interfered by other equipment and if interfered
possibly by the equipment like transmitting antenna, non
professional radio station and cellular phone.
2.TV set:
Symptoms Possible cause
Unable to switch the power on Check to see if the power plug has been inserted
properly into the socket.
No picture and sound Check to see if the power supply of liquid crystal TV has
been switched on. ( as can be indicated by the red LED
at the front of the TV set)
See if it’s receiving the signal that is transmitted from
other source than the station
Check if it’s connected to the wrong terminal or if the
input mode is correct.
Check if the signal cable connection between video
frequency source and the liquid crystal TV set is correct.
Deterioration of color phase or
color tone Check if all the picture setups have been corrected.
Screen position or size is not
proper
Check is the screen position and size is correctly set up.
Picture is twisted and deformed Check to see if the picture-frame ratio is properly set up.
Picture color changed or colorless Check the “Component” or “RGB” settings of the liquid
crystal TV set and make proper adjustment according to