Sanyo LCD-42XR8KH, Service Manual

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13
Trouble shooting
1. Fault clearance
Before servicing please check to find the possible causes of the troubles according to the table
below.
1.1 Antenna (signal):
Picture is out of focus or jumping
z
Bad status in signal receiving
z
Poor signal
z
Check if there are failures with the electrical connector or
the antenna.
z
Check if the antenna is properly connected.
Fringe in picture z Check if the antenna is correctly oriented.
z Maybe there is electric wave reflected from hilltop or
building.
Picture is interfered by stripe shaped
bright spots z Possibly due to interference from automobile, train, high
voltage transmission line, neon lamp etc.
z Maybe there is interference between antenna and power
supply line. Please try to separate them in a longer
distance.
z Maybe the shielded-layer of signal wire is not connected
properly to the connector.
There appear streaks or light color
on the screen z Check if interfered by other equipment and if interfered
possibly by the equipment like transmitting antenna,
non-professional radio station and cellular phone.
1.2 TV set:
Symptoms Possible cause
Unable to switch the power on z Check to see if the power plug has been inserted properly
into the socket.
No picture and sound
z
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)
z See if it’s receiving the signal that is transmitted from other
source than the station
z Check if it’s connected to the wrong terminal or if the input
mode is correct.
z 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 z Check if all the picture setups have been corrected.
Screen position or size is not proper z Check is the screen position and size is correctly set up.
Picture is twisted and deformed z Check to see if the picture-frame ratio is properly set up.
Picture color changed or colorless z Check the “Component” or “RGB” settings of the liquid
crystal TV set and make proper adjustment according to the
crystal TV set and m rope adjustment
Trou T ble hooting
onn th creen a, nna ten an ng ittin ans tra ke nt li en pm qui qu e the ly b sibly y ly