Tv shuts off when you turn it on again it will play a minute
I think this might be bad/swollen capacitors in your power supply, or something odd in the +5VDC circuits of the power supply, but I am posting all of the things I have found so far with these TVs.
Here are few possible solutions:
If you have no red light and you have a Megmeet MLT386 power supply, check these parts:
1) Swollen caps on the PS secondary circuit (may cause the red light blink or shutdown problems).
2) Blown fuse F1 (5A/250V) this is caused by a shorted FET at QA1 (20N60), you may also find that SMT cap CX23 is burned up (.001uf) which is in parallel with diode DA2 which may be damaged/shorted, replace these components.
If the power LED goes from red to green when powered up but no picture, then it might be lost +24VDC from the power supply:
3)Check fuse F2 (3.15A/250V, I put a 5A in), if it is blown, replace FET at QA2A (9N50C), replace QA2 as well (9N50C). Check SMT resistors at R233,R234,R235,R236 (.47 ohm). If open, replace with .1 ohm 1W or 2W resistor (easier to source). Also replace SMT transistor QF1 (2X4 or 2N4401 NPN transistor). And replace diodes at DS2 and DS1 (HER207), DS2 was shorted, DS1 was ok but I replaced it anyway.
I dont know as much about the Megmeet MLT169A, but it has similar problems and similar components.
4) I had to replace all of the capacitors in the secondary circuit (there are six in a 3x3 row marked EC9 (1000uf35V),EC10(1000uf35V),EC14(470uf35V) and EC18,EC19,EC20 (all 1000uf35V).
OK for the Megmeet MLT169A with red flashing LED when turned on we found that IC7 was bad. This is an SMT component on the solder side of the power supply. It is a 4407P (P channel 30V MOSFET). For testing purposes, we jumped across it to feed +5V to the TV permenently instead of allowing +5V to go into standby.