Thursday, December 03, 2015

SONY KV-28LS35B How to enter to service mode - led blinking code and circuit diagram


Contents of this article 

  • Standby Power led blinking 
  • How to enter self diagnostics mode
  • How to enter service mode  
  • Factory adjustments 
  • Schematic diagram 

SONY KV-28LS35

SERVICE MODE LED BLINKING CODE AND CIRCUIT DIAGRAM 

SELF DIAGNOSTIC SOFTWARE
The identification of errors within the FE-2 chassis is triggered in one of two ways :- 1: Busy or 2: Device failure to respond to IIC. In the event of one of these situations arising the software will first try to release the bus if busy (Failure to do so will report with a continuous flashing LED) and then communicate with each device in turn to establish if a device is faulty. If a device is found to be faulty the relevant device number will be displayed through the LED (Series of flashes which must be counted) See table 1., non fatal errors are reported using this method. Each time the software detects an error it is stored within the NVM
LED BLINKING CODES 
Error Message
LEDCode
No error
0
Reserved
1
Ocp (over current protection ) 
2
Not used
3
No vertical sync
4
IKR error at power on
5
IIC bus clock and or data lines low at power on
6
Nvm no IIC bus acknowledged at power on
7
Not user
8
Tuner no acknowledged at power on
9
Sound processor error
10
Jungle controller 8 volt error
11


How to enter
1. Turn on the main power switch of the TV set and enter into the ‘Stanby Mode’.
2. Press the following sequence of buttons on the Remote Commander.
(ON SCREEN DISPLAY ) > (DIGIT 5) >  (VOLUME -) > (TV)
CIRCUIT ADJUSTMENTS
How to enter into the Service Mode
1. Turn on the main power switch and enter into the stand-by mode.
2. Press the following sequence of buttons on the Remote Commander.
(ON SCREEN DISPLAY) >  (DIGIT 5) > (VOLUME +) > (TV)
‘TT—’ will appear in the upper right corner of the screen. Other status information will also be displayed.
3. Press ‘MENU’ on th 4. Move to the corresponding adjustment item using the up or down arrow buttons on the Remote Commander.
5. Press the right arrow button to enter into the required menu item.
6. Press the ‘Menu’ button on the Remote Commander to quit the Service Mode when all adjustments have been completed.
Note :
# Before performing any adjustments ensure that the correct model has been selected in the ‘Model Setting’ menu.
# After carrying out the service adjustments, to prevent the customer
accessing the ‘Service Menu’ switch the TV set OFF and then ON.
Sub Colour Adjustment
1. Receive a PAL colour bar signal.
2. Connect an oscilloscope to Pin 5 of CN003 [A Board].
3. Enter into the ‘Service’ service menu.
4. Adjust the ‘Sub Colour’ data so that the Cyan, Magenta and
Tuner AGC Adjustment
Note:
There should be no need to adjust the AGC as this is pre adjusted during manufacture of the FRONTEND. If the AGC does need adjustment then follow steps 1. to 4. below.
1. Receive a signal of 62dBuV / 75 ohm terminated via the tuner antenna socket.
2. Connect a voltmeter to pin1 of TU101 [print side of A Board] or to the AGC pin of CN001 [mount side of A Board].
3. Confirm that the AGC voltage is 3.5volts +/- 0.3volts.
4. If adjustment is required, then re-adjust the AGC variable resistor (located at the top rear of the FRONTEND) to obtain a voltage of 3.5V +/- 0.3V.
Sub Brightness Adjustment
1. Input a Monoscope pattern.
2. Press ‘TEST’ ‘TEST’ 13 on the Remote Commander.
3. Adjust the ‘Sub-Brightness’ data so that there is barely a
difference between the 0 IRE and 10 IRE signal levels.
Sub Contrast Adjustment
1. Input a video signal that contains a small 100% white area on a black background.
2. Connect an digital voltmeter to Pin 10 of J701 [C Board].
3. Adjust the Sub-Contrast [‘TT11’] to obtain a voltage of 105 +/- 5V.
CIRCUIT DIAGRAM 
CLICK ON THE IMAGE TO ZOOM IN