LL-T15S1 (serv.man7). Chapter 5 - Troubleshooting — Sharp Monitor Service Manual (repair manual)

Model
LL-T15S1 (serv.man7)
Pages
3 Few pages! See other manuals at the bottom of the first or last page.
Size
17.34 KB
Type
PDF
Document
Service Manual
Brand
Device
Monitor / Chapter 5 - Troubleshooting
File
ll-t15s1-sm7.pdf
Date

View Sharp LL-T15S1 (serv.man7) Service Manual online

CHAPTER 5. TROUBLESHOOTING
No power supply
Does LED turns on in green 
when power switch is turned 
on?
No
No
No
No
No
No
LED turns on in red?
Yes
Yes
Yes
Yes
Yes
*  Check LED for breakage.
*  Check the path between JP2 (9pin) and 
U11(27pin).
*  Check cable for disconnection.
Replace any unit (main PWB, SW PWB, cable 
Power jack) which shows any defect, with a new 
1) PC is turned off?
2) RGB cable is disconnected?
3) Synchronizing signal is output from RGB 
cable?
Check whether the unit is in power save 
mode (synchronizing signal is not input.).
Synchronizing signal is input to main PWB?
Replace RGB cable 
with a new one.
LED turns on in orange?
Check power input system.
1) AC adapter
   *  Normal?
   *  Connected properly?
2) Blown out fuse (F1) or power jack PWB?
3) EEPROM (U11) has +5V (VCC)?
4) LED
   *  Check LED for breakage.
   *  Check the path between JP2 (9pin) 
and U11 (27pin).
   *  Check the cable for disconnection.
Replace any defective unit.
[ 1) Adapter, 2) A Main PWB, 3) Switch 
PWB, 4) Power jack PWB] with a new one.
Backlight turns ON?
Check for RGB cable input 
signal.
Replace RGB cable.
Check each pin terminal 
of JP5.
Normal
Normal
Normal
Defective
Defective
Check output circuit to JP5.
1) If +12V is NG, replace main 
PWB.
*  Check inverter PWB unit.
Note: Use caution when checking output 
side because it has a high voltage. 
(1400 Vrms when starting)
Replace LCD module lamp with 
a new one.
Replace inverter PWB 
unit with a new one.
A
A
Screen does not operate normally.
Check RGB cable.
Defective
Replace RGB cable with 
a new one.
Check screen condition by changing display modes.
Reset the microprocessor to check if screen condition changes.
(Press and hold MENU and SELECT buttons while turning on power switch.)
Screen stays in black.
Screen stays in white.
Screen jitters or on-screen 
characters flicker.
Abnormal color
Check the following signals
1) Check if module control signal is output.
2) Check if gate voltage is output normally.
3) Check if Source voltage is output normally.
Yes
No
Yes
No
Yes
No
CLOCK and PHASE 
can be adjusted?
Does abnormal area move on 
screen when BLACK LEVEL or 
CONT is changed after H-POS 
or V-POS is set?
Switch PWB defective
Main PWB defective.
LCD panel defective.
<Voice output error>
+12 V DC at 1st and 2nd pins of JP1?
Signal input of 4th pin of U12 is at H level
(+5 V DC)?
Check mute input circuit of I/F board.
Input signal of 3rd and 5th pins of U12 is normal?
Check power supply, vo ice input and voice
input circuit of I/F board.
Signal input at 1st and 7th pins of U12 changes
when voice volume is changed.
Check control PWB and the volume circuit
around U11.
Signal output at 8th, 10th, 11th and 13th pins of
U12 is normal?
Check amplifier circuit around U12.
Check speakers and speaker cables.
• Check connection of JP1 connector.
• Check fuse F1 of Power Jack PWB.
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Download Sharp LL-T15S1 (serv.man7) Service Manual (Repair Manual)

Here you can view online or download Sharp LL-T15S1 (serv.man7) Service Manual in pdf. This Service Manual can help you recover, restore, fix, disassemble and repair Sharp LL-T15S1 (serv.man7) Monitor. Information contained in Sharp LL-T15S1 (serv.man7) service manual (repair manual) typically includes:

  • Disassembly, troubleshooting, programming, maintenance, remote, adjustment, installation and setup instructions.
  • Schematics, wiring and block diagrams.
  • Printed wiring boards (PWB) and printed circuit boards (PCB).
  • Parts list (bill of materials).