Changed a 3300mf 100 volt capacitor in power supply was blown when i plug tv in red light standby light comes on then i hold in power button blue light on light comes on it doesnt flash but no picture or sound at all

Screen coming on when the main plug is removed is normal, that happens on most TV's...Are the spots that have no volts supposed to have voltage? there is a legend on the board to tell what voltages belong no what pin, check that

My Samsung 50 inch had the same problem. Searched the web and it was the only capacitor in the power board that needed change, voltage was 382 volts. Replaced the old 100 uf 450 volts capacitors with two capacitors 150 uf 400 volts and 220 uf 400 volts in parallel and measured the high voltage at 390 and the TV was back to normal. (Make sure the capacitors from an old TV and computer power supply is rated for at least 400 volts.

try this Press and hold the on/ off button Whilst holding unplug the plug from the wall Continue holding for 30 seconds Plug in the plug whilst continuing to hold the on/ off button Continue to hold for a further 30 seconds And the screen should come back on, good luck

shaun

Suspect power supply board.
Look for some poped capacitors or other components like fuse/power transistors

Repair No Power Power Supply Common Symptoms Solutions How to...

and

Fixing the Blown Capacitor in Samsung TV Yourself LCD TV

My Samsung started doing that and it got worst and worst. Searched the web and find answer. It was the high voltage circuit. All TVs now are like computer and it check for 390 to 400 volts and if it is below, the TV will not turn on. Good thing the Samsung has only one capacitor showing the high voltage circuit. Measure the voltage was 381 volts. The capacitor was rated at 100 uf at 450 volts. From some old TV and power supply, got two capacitors rated 150 uf and 220 uf both at 400 volts. Had to connect them in parallel and took out the old capacitor. Now, my TV works fine.

Sounds like your power supply capacitors have failed. Google for Z1234TV and see if you can locate a power supply capacitor repair kit for your model.

Hi
A common problem for these is bad capacitors in the power supply, Remove the back from your Tv and look at the power supply on the left hand side.

You will see roughly around 9 x capacitors that are bulged / domed shaped on top usually these are valued at 3300uf 10V any that have bulged or leaked a brown like substance should be changed.
This will cure the problem as they overheat being sat next to a heatsink that gets very hot!
Try and change them for the same 3300uf but a higher voltage.
Hope this helps