Tuesday 3 September 2019

LC26GD7E Sharp AQUOS LCD COLOUR TELEVISION (Display) – how to enter the service mode, software update, error codes, SMPS and inverter schematic


Sharp AQUOS Widescreen HD ready LCD TV – LC26GD7E
To Enter the service mode
Pre-setup position: set should be  in TV mode
1. Press MENU button on top of the TV set to enter menu „direct control on tv set“ (fig. 1, pos. 1)
2. Press button "P Up"until "service"is shown in menu (fig. 1, pos. 2)
3. When service appears press the MENU button on the remote control within 1 sec (fig. 2, pos. 3).
Service menu appears.
4. Step with cursor buttons on remote control (fig. 2, pos. 4) through the service menu to change settings.
5. Each modification of any value has to be memorized with the "OK" button on remote control (fig. 2, pos. 5).
Service menu L2650 (LCD)
Adjustment
The adjustment values are set to the optimum conditions at the factory before shipping. If a value should become
improper or an adjustment is required due to part replacement, make an adjustment according to the following
procedure.
1. Display adjustment procedure
1. Adjustment procedure
To Enter the display process mode and then adjust COM BIAS.
Caution: Use due care in handling the infomation described here lest your users should know how to enter the adjustment process mode. If the settings are tampered in this mode, unrecoverable system damage may result.
Adjustment process mode key operation table.
COM BIAS adjustment
Shift to the [COM BIAS] item with the cursor UP/DOWN key and select a numeric value with the cursor RIGHT/LEFT key.
Changing the numeric value with the cursor UP/DOWN key will make appear the test pattern. 
Make an adjustment so that the flicker near the center of the screen is minimized.
Lamp error detection
Feature description
This liquid-crystal color TV incorporates a lamp error detection feature (lamp error detection) that automatically turns OFF lamp drivers if any one lamp fails.
If anything is wrong with the lamp or lamp circuit or when the lamp error detection failure is activated for some reason, the following will result: All lamps are switched off the audio remains and green led keeps ON.
After switching on and off lamps go on for around 1 sec. until lamp error detected.
Measures
a) With lamp error in on mode (green led on) its possible to check the power supply (15 V for lamp inverters)
b) Test on inverter circuit is only possible in the first moment after switching on until protection circuit cuts driver signals for all lamps.
A simple test to find out which lamp inverter does not work: Check with oscilloscope the signal directly on core of inverter transformers.
Resetting of lamp error counter
After successful repair of lamps or the inverter circuit, you have to reset the lamp error counter through service mode.
For resetting go to LCD adjustments in service mode. With "Dn" go to panel service.
Press now first green button and then ok button on remote control
 (Attention: for protection the green button is not mentioned in on screen menu)
Red panel service menu comes up on screen.
Move cursor with "Dn" down to “L ERR Reset” and move to right side with “Right”button.
Press any cursor to reset lamp error to “0”.
After resetting to "0", perform an operational check to ensure that the lamp error detection feature is not activated.
Error codes [Monitoring process ERR STBY table]
Communication and power failures detected by the monitoring microcomputer are saved to EEPROM, and the final states of the errors can be checked in the monitoring process.
Location: Line 3 in page 0 of the monitoring process, ERR STBY field If there is no error, 0 appears. Value can be cleared to 0 using the cursor.
Red power LED: P2304 (RM), pin 8
Green : TP2301 (IC2301, pin 22)
Firmware update
Update of the main software (operating software)
To update the software you need the "Programmer" and the update program "Flasher".
Procedure
- Switch off the TV set with the mains switch.
- Connect the Programmer with the L-Link cable to the service socket at the TV.
- Start the Flasher software and select „Step 2“ (see fig. 1)
- Switch on the TV set with the mains switch now (TV does not switch on under this condition) – see fig. 2
- Software automatically jumps to "Step 3"
- Now select „Auto program“ (see fig. 3)
...and select the new software version (see fig. 4).
With selecting "Open" the update process will start automatically (see fig. 5).
- With the message "Flash programmed" the update is finished (fig. 6).
- Switch off the TV with the mains switch and disconnect the L-Link cable.
Update of the DVB Bootload- / Application software
To update the software you need the "Programmer" and the update program "Dvbpromer".
Follow steps 1-6 shown in the following pictures.
LED flashing patterns for error notification.  [Connect a LED to P2304 for blinking codes]
Power LED: P2304 (RM), pin 8
Alarm LED: TP2301 (IC2301, pin 22)
Power [SMPS] schematic
Inverter unit schematic
Inverter GND unit schematic