THE BLINKING LED PROCEDURE
Using this procedure you can make the contents of the error buffer visible via the front LED. This is especially useful when there is no picture.
- When SDM [Service Default Mode] (refer the previous post), is entered, the front LED will blink the contents of the error buffer.
- The LED blinks with as many pulses as the error code number, followed by a time period of 1.5 seconds, in which the LED is OFF.
- Then this sequence repeated.
After entering SDM, the following occurs.
- 1 long blink of 5 seconds to sttart the sequence.
- 12 short blinks followed by a pause of 1.5 seconds.
- 9 short blinks followed by a pause of 1.5 seconds.
- 6 short blinks followed by a pause of 1.5 seconds.
- 1 long blink 1.5 seconds to finish the sequence.
- The sequence starts again with 12 short blinks.
It is assumed that the components are mounted correctly with the correct values, and no bad solder joints.
Before any fault finding actions check if the correct options are set.
In some cases , it can be handy if one directly can change the NVM contents. This can be done with "NVM editor" in SAM mode. With option single bytes can be changed.
Caution:
- Do not change the NVM settings without understanding the function of each setting, because the incorrect NVM settings may seriously hamper the correct functioning of the TV set.
- Do not change the Scaler NVM settings, as this will hamper the DVI functionality of the TV set.
- Always note down the existing NVM settings, before changing the settings. This will enable you to return to original settings, if the new settings turn out to be incorrect.
In case, a blank NVM is placed or when the NVM content is corrupted, default values can be downloaded into the NVM. For empty NVM replacement, short the SDM with a jumper and apply mains voltage. Remember to remove the jumper after reload is completed. After default values are downloaded, it will be possible to start up, and star aligning the TV set. This is no longer initiated automatically; to initiate the download the following actions should be performed.
- Switch OFF the TV set by disconnecting the AC power plug.
- Short circuit SDM jumpers. Keep short circuited.
- Press P+ and CH+ on the local keyboard, and keep it pressed.
- Switch ON the TV set via AC power plug.
- Keep pressing P+ / CH+ button, until the set has started up and the SDM is shown.
- Go to SAM.
- Select NVM editor [not sc NVM editor]
- Select ADR (Address) to 1(dec)
- Change VAL (value) to 170 (dec).
- Store the value.
- Disconnect the mains plug and wait for a few seconds.
- Reconnect the mains plug and wait untils the set goes into its standby mode.[red light lights up]
- Restart the set.
No picture in RF mode, but there is a Noise Raster.
- Check whether picture is present in AV. If not go to video processing troubleshooting section.
- If present, check the Option settings are correct.
- Check if all the supply voltages are present [3.3 / 5 / 8 / 12 / 33V].
- Check I2C lines are working correctly [3.3V].
- Manually store a known channel and check if there is IF output at Tuner pin [11].
- Check the DC tuning voltage at pin number [2] of the tuner. This voltage should vary according to the frequency / channel being chosen.
- If the tuning voltage is OK, check the tuner output pin [11].
- If it has no output, the Tuner may have defect. Change the Tuner.
- Check whether AGC L in 'SAM' mode is set to [0].
- If yes, align the set to correct value.
Check whether a service jumper (#4204 & 4205, 0805size) is present. If yes, remove it.
NO POWER
- Check +12V and 3.3V at position 1J02.
- If no supply, check the connector 1J02.
- If it is correct, check the power supply board.
- Check the connections 1K100 are properly inserted.
- If they are inserted correctly, check if 3.3V is present.
