Tv Grundig Vision 2 22-2920 turn off after 2 secs

[stomanata]

Re: Tv Grundig Vision 2 22-2920 turn off after 2 secs

No luck...
I connect VCC and GND over FAN7314.
Also ENABLE of driver over pin #3 of FAN.
ADJ of driver first i try over pin #8, but it start too bright
and led strip start to blink.
Then i try over pin #7 of FAN, but it is the same.
Now i wonder if i connect resistor in series of ADJ.
It must be PWM there...
Other solutions?

[budm]

Re: Tv Grundig Vision 2 22-2920 turn off after 2 secs

https://www.badcaps.net/forum/attach...9&d=1587475013
Can I see good clear focused pictures of the whole top and bottom side of the board?
What you need to do is to disconnect the power (12V) feeding the inverter section so the inverter section will not be running so no need to deal with any protection section for the CCFL, the lines feeding the ON/OFF and Dim control signals.
BTW, what is the spec of the LED driver ADJ signal requirement? AnaloG? PWM?

[stomanata]

Re: Tv Grundig Vision 2 22-2920 turn off after 2 secs

https://www.badcaps.net/forum/attach...9&d=1587475013
Can I see good clear focused pictures of the whole top and bottom side of the board?
What you need to do is to disconnect the power (12V) feeding the inverter section so the inverter section will not be running so no need to deal with any protection section for the CCFL, the lines feeding the ON/OFF and Dim control signals.
BTW, what is the spec of the LED driver ADJ signal requirement? AnaloG? PWM?

This must be better. On my pc i can zoom enought to see all details.
For inverter i remove both mosfets that drive HV transformer and use
560 ohm resistor to ignore OLP.
Inverter is based on DF6113. In datasheet is labeled to use series resistor for DIM...

[stomanata]

Re: Tv Grundig Vision 2 22-2920 turn off after 2 secs

Even with 100k pot in series is the same.
BTW it start may be normal and after 4-5-6 secs it
start to blink.
What about if i remove FAN7314 chip?

[nezocas]

Re: Tv Grundig Vision 2 22-2920 turn off after 2 secs

Hello,

I know this is an old thread.... but I have the same set, with same PSU.
Initially I had no backligth....just sound and image (visible with a powerfull torch).

I went strait to the transformer, one of the secondary winding was 1.8K the other was correct 1.3K.

Changed it with same part number, and still no backligth.
To avoid dissassembly the LCD to check the lamps, I plugged 4 laptop screens (old ones with lamp) to the tv. Only 2 will ligth up for 2 seconds.

Placed the 560homs resistor and backligth will stay ON on the same 2 lcds. The other ones dont even blink (S2009 and S2008).

Allready changed the FAN7314 but NO changes.
I have also checked the four 3Kv caps but all OK.

Were should I check futher?

Best regards
Nezocas

[nezocas]

Re: Tv Grundig Vision 2 22-2920 turn off after 2 secs

Hello,

I know this is an old thread.... but I have the same set, with same PSU.
Initially I had no backligth....just sound and image (visible with a powerfull torch).

I went strait to the transformer, one of the secondary winding was 1.8K the other was correct 1.3K.

Changed it with same part number, and still no backligth.
To avoid dissassembly the LCD to check the lamps, I plugged 4 laptop screens (old ones with lamp) to the tv. Only 2 will ligth up for 2 seconds.

Placed the 560homs resistor and backligth will stay ON on the same 2 lcds. The other ones dont even blink (S2009 and S2008).

Allready changed the FAN7314 but NO changes.
I have also checked the four 3Kv caps but all OK.

Were should I check futher?

Best regards
Nezocas

SOLVED,
Received bad transformer, and it had good readings in the primary and secondary sides.
Replaced transformer from a scrap board. It was also a blue transformer from 17IPS15-4 power supply with diferent part number TMS93700CT.

Regards