Technivision 22 wont switch channel. Dead Buttons on TV

[Mr_K]

Here i have a Technisat Technivision 22. (German budget brand) The TV won´t switch the channel. All the buttons on the TV are dead. I can power on the TV with the remote and use SOME other buttons like VolUp. But most of the buttons are also dead. Ch+, Menu, all the numbers.......

Any advise on this one?

[selldoor]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Maybe stating the obvious but removing cleaning and replacing the buttonboard
might help

[RJARRRPCGP]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Reminds me of my GE window air conditioner.
I must use the remote just to even turn it on since the buttons got wet in August, 2005.
I got it on August 20, 2003.

[Mr_K]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Ok, i disconnected the buttonboard. I have full control with the remote now. Even with the buttonboard reconnected. The buttonboard is still dead. Its a very simple board with just the buttons and some resistors. These components are fine. I fear the fault might be on the main pcb.....?

[johnboy1313]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

I would say if the tv works with the button board disconnected then the button board is likely bad.

[selldoor]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Ok, i disconnected the buttonboard. I have full control with the remote now. Even with the buttonboard reconnected. The buttonboard is still dead. Its a very simple board with just the buttons and some resistors. These components are fine. I fear the fault might be on the main pcb.....?

Did you check for continuity on each wire in the cable



EDIT EDIT
Can you post a picture of the are where the buttonboard connect to the main

[Mr_K]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Cable is good.
Button board is tested good.

Some Pics:
Buttonboard is Con3
Gnd (black) to C67,
Key0 (blue) to R57 and R59,
Key1 (orange) to R60 and R56

[selldoor]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Any voltages recorded between key and ground when a button is pressed
(try all) - Test the resistors and caps mentioned at least for continuity.
Can you tell where the circuits go after those components.
If I recall we have had you doing very similar things on something else a few months back?

[Mr_K]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Voltage between key and ground is 3.3V and dropping when a button is pressed.
Resistors and Caps seem fine.
R59 and R60->to the big IC
R57->R70 and RP8
R56->RP10 and RP13

No, i think you are wrong. The last time i asked for help was a faulty samsung PSU. (Missing 12V and 24V)

[selldoor]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

I dont know what RP8 is but in the pic it looks a bit odd - pitted at the top.
Can you have a look with a magnifier.

Have you been able to find a reset sequence or a way to get to service menu?
I will try and have a look tomorrow.

[anno]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Nevermind sorry

[Mr_K]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

I dont know what RP8 is but in the pic it looks a bit odd - pitted at the top.
Can you have a look with a magnifier.

Have you been able to find a reset sequence or a way to get to service menu?
I will try and have a look tomorrow.

I think its just an network of resistors?!? Will check the rest now.....

[Mr_K]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

FIXED IT!
FYI: No service menu needed. All options are accessable from the normal menu. With button board connected, go to menu->Hotel menu->set Disable buttons to on. Than push one of these buttons. The "Disable buttons" toggle will automaticly swith back to off. Exit with pressing menu again.
Thats how i fixed it. Still do not know what caused the problem. Will keep an eye on it.....

Big thanks to everyone for your support (again) If you are interested you can hava a look at my samsung PSU thread. This one still needs a fix.

[selldoor]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Well done.! I will still have to look at those resistors clumps - have not been aware of them before.
Did you mean the samsung or the Phillips. I was thinking of the phillips one. Tom and Bud were probably your best bet skimming through checking all the remaining big components
would seem to be all that is left. You tetsted some of the the fusible resistors but did you check them all?

[Mr_K]

Re: Technivision 22 wont switch channel. Dead Buttons on TV

Oh my bad, i mean the Phillips. Lets keep it to the right thread.....