Sharp TU-DTV1000/A, Service Manual

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14
TU-DTV1000/A
TROUBLE SHOOTING TABLE (Continued)
No video output, no audio output
First make sure of the following points.
»
The AC power cable is plugged in.
»
The power is switched on and the unit’s power LED stays on.
»
The output mode switch is properly set according to a monitor
to be connected.
→
Refer to “VIDEO CONNECTIONS” (pages. 32 and 33) of
the Operation Manual.
»
The video and audio cables are correctly connected.
Can a channel be selected (channel number displayed on screen)?
Check the D5212 and D5213 on the ATV-1 PWB.
Green LED on, red LED flashing: This means the IC5101 (SH3) functions. Check the
following parts.
»
ATV-1 and ATV-2 connection cables (SC5103)
»
ATV-1 FPGA (IC5105)
»
ATV-2 MMC (IC5424 and IC5429)
Green LED off, red LED on or off: This means the SH3 or other part malfunctions.
Check the following parts.
»
SH3 (IC5429), FPGA (IC5105), SDRAM (IC5102 and IC5104), ROM (IC5111 and
IC5112), Flash (IC5113 thru IC5116)
Make sure of the following points: selected
channel number displayed on screen, antenna
cable properly connected, reception condition
by HDTV indicator on front panel.
Is the HDTV indicator either on or off (not
flashing)?
YES
YES
YES
NO
NO
NO
1) Slow flashing
There is no DTV program available for a selected major channel, or if any, the
signal reception condition is too bad to receive clearly.
→
Select another channel with DTV signal and try again.
2) Quick flashing
There is a DTV program available for a selected major channel, but the signal
reception condition is too bad to receive clearly.
→
Select another channel with DTV signal and try again.
3) Intermittent flashing
There is a DTV signal for a selected major channel and the signal is well received,
but minor channels are not properly set (example: 02 of 23.02) (There is no
program for a selected minor channel.)
→
Set another minor channel or select another major channel.
If another channel is tried but the indicator is still flashing, check the tuner
(TU5001) and the VSB (UNT5001).
Select a channel without DTV program.
Is the HDTV indicator flashing?
Select a channel with DTV program again. (Make
sure the indicator stays on or goes out.)
ATV-1 ST20TP2 (IC5001) malfunctioning
Turn off the power and turn it on again. If the
ST20TP2 still malfunctions, check the ST20TP2
(IC5001) and RAM(IC5009 and IC5010) for trouble.
A