[lcaillo]

The 1-2 code means no shutdown error. This means that the set is either not starting or is not going into protection. You will need to identify what is running and what is not. Do you hear the "crackle" of high voltage when you start or shut off the set? Are the filaments at the bottom of the CRTs lit?

 

[lcaillo]

If you get any LED activity you know that the standby supply is present and the micro is running. I'd be looking for power supply voltages. Are you sure that the code was 1-2 and not 2-1?

 

[lcaillo]

If the code is 1-2 then there is no shutdown condition. The set is likely never starting up at all. Start by identifying power supply voltages. Standby 5v will likely be present, but others will likely not come up at all.