Sharp TU-DTV1000/A, Service Manual

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15
TU-DTV1000/A
TROUBLE SHOOTING TABLE (Continued)
Check the LEDs (D5023, D5024 and D5025) on the
ATV-1 PWB. Does the D5023 light up in green?
NO
YES
YES
NO
A DTV signal (available in the selected channel) is
locked.
There is no DTV signal for the selected channel.
Check the tuner and VSB unit for trouble.
Does the D5024 light up in green and the D5025
(red) go out?
The tuner and VSB function well. Check IC5001
and IC5003 for trouble.
If D5025 starts flashing or stays on in red, it means
the reception condition is bad with many errors.
`
Because of poor reception condition, DTV programs may be affected by the VSB out of lock (D5023 off) or reception error
(D5025 on or flashing). Possible causes include:
»
that signals being received by the antenna are too weak or too strong.
»
that received signals contain remarkable ghost and other interference.
A
»
Make sure the video cable is
properly connected.
»
Make sure the video output
mode corresponds to a monitor
being hooked up.
No video output (audio output available)
Does the on-screen display function well (by using the R/C unit)?
Check the D5212 and D5213 on the ATV-1 PWB.
Green LED on, red LED flashing: This means the SH3
(IC5101) 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)
See if the ATV-1 and ATV-2 connection cables (ATV-1
connector SC5411) are connected tightly. Check the
ATV-2 video decoder (IC5403), SDRAM (IC5405, IC5406
and IC5407), FPGA (IC5408) and SDRAM (IC5412 thru
IC5415) for trouble.
YES
NO