Thomson tv model R21DGB8GBD av switch is not working,ie didn't change the grain

first is to get it from AV mode which suggests it is on one of the rear audio/video inputs.

If no source or Tv video button on remote look in the menu--once off the AV input it should be able to tune.

Direct hookup with cable or what?

no tunning available on av just set av channel inputs

what you describe is almost impossible ..the only explaining is someone with a compatible remote control messing around with you ..so ...pay attention ..and after that if you are completely sure that this is out of case...Leave a comment and I will search for another possible cause ..

it sounds like you have an av switching fault .
This is on a printed circuit board .
This fault and cre should be checked by a competant service engineer

this tv is not a dtv tv you can only watch digital tv if you now have a freeview box this is conected via a scart lead . you select av on the tv remote . or you can watch sky or cable . these are connected the same way .

Try the other channel.
If both are set to channel 4, change both to channel 3.
If both are set to channel 3, change both to channel 4.

The manual is not very clear.
The volume control will work after entering the code for your TV make.
Press TV
Press AV and OK together and wait. The TV button will flash twice eventually.
then using the numeric keypad enter the code ie 0680 for Panasonic,
a list was provided with your instructions.
On entering the code the TV button will flash twice again t confirm.
Now the volume of the TV can be controllled using the buttons on the Thomson remote.
Teletext and other functions like "mute" are now present.
peterh

I cannot change from tv to av with the remote how do I do it the model number is 20071025

need sequence to tune in remote controller

You didn"t say already working in AV mode or not. Suppose if it is worked means this is the simple one just change programme (-) button in TV front panel till becomes 1 or 0. After 1 or 0 again you press down the same button you get AV mode. Even you won"t get try in menu features to change AV mode. Even you won"t get there is a problem in Micom section. Technical persons only sort out your problem by changing EEPROM ic. I hope the above information is useful to you.