Polaroid 37 in has blue light when powered on, however, no signal comes on screen, We have wii hooked up to it and it works fine, Any suggestions? Thanks

SOURCE: Polaroid LCD

It looks like your power supply might not be providing enough current to get the LCD to power up. This LCD needs about 3 to 4 amps to work properly.

SOURCE: 37" Polaroid LCD TV No signal appears when select channel

I was having same problem, and think I got lucky and found fix.

Try unplugging the TV and waiting 30 seconds, then plug back in.

You will likely get blue screen with "No Signal".

Go to Menu, then scroll down to "Setup". Select "Factory Reset" then hit "Yes."

This did it for me. Wish you all luck.

SOURCE: blue power light flashes No picture on a 37 HDTV/LCD Polaroid -

this might help

http://www.fixya.com/support/r741402-polaroid_flm_373b_lcd_tv_black_screen

SOURCE: 37"polaroid FLM-373B

Follow this link and read all comments/instructions. I have the Polaroid FLM 3732 37 inch and about a week ago this same problem occurred. I did not have the money to fix it, or get a new tv so I was pretty bummed. Then I found this site. 
http://www.fixya.com/support/r741402-polaroid_flm_373b_lcd_tv_black_screen

I am a single mom (girly girl) age 40 who has never done any kind of electronics work or soldering, but I was able to fix my TV following these directions and there is also a youtube tutorial for these exact problems. 
http://www.youtube.com/watch?v=_0175VbmV9M


I fixed it for under $30, and I am so proud and also earned some "street cred" with my 14 year old son!!
Polaroid is ripping people off left and right...it's disgusting but now I feel like I bucked the system for once!!

SOURCE: 37" Polaroid HD LCD black display but appears to be "on"

The power supply board was having problems before.That the board,where the power a/c cord plug into it Now might also the Tuner board are dead too.The tv Tuner board,that the board where the tv broscast signal cable plug into it.That the Tuner board.Tries Websites like shopjimmy.com,Ebay.com to buy a refurbish power supply board for the replacement to see if solved the problem,not probally will have to buy the refurbish Tuner board for the replacement too.