I have a sharp tv lc40le431u .put in main board now picture is upside down

Go to service mode and there should be an option to flip the picture, not sure why this should happen when selecting reset as its more common when replacing the main board

There will be some adjustments to do, after the replacement of this board. If you wish to get some details; visit the site linked here. Pull up older posts. http://electronicshelponline.blogspot.com/
Can't make sure about it. Sometimes there might be no more adjustments. Contact any service technician, and make sure about this.

If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/

If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
Reasons for upside down picture are given.

When you ordered you replacement board was it specific for your model or did you order by board number, if so it may not be compatible with your TV

If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/
Faults & possible causes to LCD screen are given with illustrations. You can get an idea about the fault to an extent.

Flip the TV over! Just kidding!! When you installed the main board was it identical to the old main board? If so, you might want to look at the old board and ensure there are no jumpers that needed to be set on the new board. Some companies make generic control boards for tvs but have different jumper settings for different models. The jumpers are just little black blocks that connect different pins to each other on top of the circuit board.

Check that the connectors are properly put on. In some models of TV sets the connectors are not keyed, and can be inserted in either direction. This would be obviously the connector that is carrying the image data to the screen.

If this is not a reversed connector, then it is most likely a firmware issue in the new replacement board. Make sure the replacement board is the exact one required for your model type.

I would suspect main board more than one you replaced--not likely to get help as Thompson is not known for that--possible firmware upgrade seems likely.

On every set I have seen with upside down/inverted or reversed screen etc it has been either a firmware issue or a main board.

Service manuals: http://elektrotanya.com/?q=showresult&megnev=SHARP&megnev2=LC52SB57UN&kategoria=&kat2=all

Did you get the correct main board that matches this TV chassis?

Basic LCD monitor and TV troubleshooting guide:
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors pictures: http://s807.photobucket.com/albums/yy352/budm
Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague
Parts: www.shopjimmy.com
Parts: http://interliquidparts.com/

Capacitors kit: http://lcdalternatives.auctivacommerce.com/Default.aspx he can make you a set of caps.
Or www.digikey.com, just make sure to use caps with low ESR, 105c, high ripple current and long life rating such as PANASONIC FM or FC series.