Read Sharp BD-HP21H (serv.man2) Service Manual online
BD-HP21U/S/H/A/X/RU/SB,BD-HP50U/X
2 – 12
(BD-HP50 Series)
The remote controller fails to function.
The main unit controls function, but the remote controller
controls fail to function.
controls fail to function.
YES
YES
Check the line between J4751 and the terminals on IC4751.
If there is no input at pin (12) of J4751, check J4751 or replace it
as required. Or check the IR receiver in use.
as required. Or check the IR receiver in use.
Check the remote control codes 1, 2 and 3.
Check the AT_5V line.
Are there the inputs at pin (12) (remote control pulse with the
same polarity as at pin (2) of J4751) and at pin (13)
(inverting pulse of the pulse at pin (12)), both on IC4751?
same polarity as at pin (2) of J4751) and at pin (13)
(inverting pulse of the pulse at pin (12)), both on IC4751?
Reposition the polarity change-over switch and check the polarity
again. (S4751)
again. (S4751)
NO
NO
NO
Check IC4751 and its peripheral circuits.
Replace IC4751 as required.
Replace IC4751 as required.
NO
Is the remote control code as specified?
NO
YES
Check the circuit between pins (14) and (1) of IC4751.
Is the signal inputted to pin (1) of IC4751?
NO
YES
Pin (10) of IC4751 at "L": IR receiver
at "H": Main unit receiver
Make sure that when the IR receiver is inserted, pin (10) of IC4751
turns from "H" to "L" level. When fixed at "H" or "L", for example,
check the line between J4751 and pin (10) of IC4751, or replace
J4751 as required. Or check IC4751 and its peripheral circuits and
replace IC4751 as required.
* With the main unit receiver in use
turns from "H" to "L" level. When fixed at "H" or "L", for example,
check the line between J4751 and pin (10) of IC4751, or replace
J4751 as required. Or check IC4751 and its peripheral circuits and
replace IC4751 as required.
* With the main unit receiver in use
Make sure the signal is inputted to pin (2) of IC4751.
Is the signal outputted from pin (15) of IC4751?
NO
Is the "L" pulse signal inputted to pin (25) of IC2504?
YES
YES
YES
Check IC2504 and replace it
as required.
as required.
Check the line between pins
(15) and (2) of IC4751.
(15) and (2) of IC4751.
NO
YES
Using the remote controller, is
the "L" pulse signal is outputted
from pin (1) of RMC1201?
the "L" pulse signal is outputted
from pin (1) of RMC1201?
Check the AT_5V line.
YES
NO
Check the line between pin (1)
of RMC1201 and pin (2) of
IC4751.
of RMC1201 and pin (2) of
IC4751.
Replace RMC1201 or the
remote control receiver.
remote control receiver.
YES
NO
Is the IR receiver used?
YES
Is the signal, which corresponds to the polarity change-over
switch (S4751), outputted from pin (14) of IC4571?
Pin (11) of IC4571 at "L": Input at pin (12)
switch (S4751), outputted from pin (14) of IC4571?
Pin (11) of IC4571 at "L": Input at pin (12)
at "H": Input at pin (13)
No signal is inputted to pin (2) of IC4751.
Is the 5V voltage applied at pin (3) of the RMC1201 remote control
receiver?
receiver?
YES
FLOW CHART No.1 (HP50U only)
With the main unit receiver in use
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