Solved! Sharp TV will power on long enough to show the 'Sharp' logo then powers off and back on to the logo

[el in va]

...we let it repeat for an hour just to see what it would do. This TV is 18 months old which i understand with sharp seems to be the kiss of death time... hoping we can get help. Will be taking the back off tomorrow...

 

[StitchExperiment626]

Most likely the power supply. Look for bulged caps on top and put in a higher voltage (25 VDC is normal so put in a 35VDC) or order a power supply board from http/www.shopjimmy.com/tvs
When pulling the wires DON'T pull the wires grab the connector from the edges and wiggle it back and forth off other than that you'll pull the wires out of the connector.

Bruce

 

[el in va]

Most likely the power supply. Look for bulged caps on top and put in a higher voltage (25 VDC is normal so put in a 35VDC) or order a power supply board from http/www.shopjimmy.com/tvs
When pulling the wires DON'T pull the wires grab the connector from the edges and wiggle it back and forth off other than that you'll pull the wires out of the connector.

Bruce

 

[el in va]

Thanks Bruce-we'll look into that today and let you know how it goes
el

 

[el in va]

i have found out from someone else with the same tv/same problem that it is the Mother Board (not the power supply) that needs to be replaced.