TCL L24D10 - Input and Audio Output Problems

VGA/YPbPr no picture
Check the components between AV port and U201
1*
Upgrade
OK 2.
AV no picture
Check the components between VGA/YPbPr port and U201
1*
Replace the bad
VGA/YPbPr no picture
OK
Check the components between VGA/YPbPr port and U201
1*
Replace the bad
Software of U202 ok?
1*
Check U201 ok?
OK
OK
1*
Replace the bad
Replace U201
1*
Replace the bad
Check the peripheral components of U201