Tv has no picture only sound

not much else to try besides replacing the mainboard.

Change input device to some other like a DVD player and see.
Switch off TV, switch off power, remove plug and wait for 48 hours and retry.

If problem persists, call in a qualified service technician.

I think you chose a Westinghouse Lemon, go this site and read all of the negative reviews of this model;

http://reviews.cnet.com/flat-panel-tvs/westinghouse-sk-32h240s/4852-6482_7-32429419-2.html?tag=userReviews;page

Here's just one of the reviews;"best chunk of aluminum i ever had the fortune to buy"by stevecox25 on June 11, 2009-->
"Horrible customer service on a worse television" by westinghousecrap on March 20, 2009 Pros: Good picture once it is properly adjusted.
Cons: Low quality audio, had the TV for 10.5 months and the picture went out, sent the TV at MY expense to TX, and I've been waiting for 2 months, and customer service can only say that there is a "delay". And they don't send a new TV, it's a rebuild.
Summary: Please don't waste your money on this TV, spend a little more on a different brand and save yourself the headaches I've had. I'll never purchase a Westinghouse product again. Customer service has been no help, and their answers are vague at best. Learn from my nightmare, NCAA march madness on a old 19" TV because my Westinghouse quit working 2 months ago and they still haven't replaced it.

Talked to a Westinghouse tech and told to unplug for about 3-5 minutes, then re-plug. It's like having to re-boot your computer when it goes down or starts acting wacky. It worked, I got picture. Says it could happen again, maybe 1-2 times a year is o.k., if it starts to happen every few weeks, then it's something more.

I had a similar problem with 2 other lcds. In one of them there were 3 capacitors that needed to be changed. In the other the main (biggest capactior) needed to be replaced. Someone may have already posted the solution for this tv with more details than I can provide.

I have the same problem - its a HDCP handshake issue. Sony says the firmware in the Westinghouse TV needs to be updated - Westinghouse says that they have firmware updates for some models depending on your TV's serial number, otherwise they are working on firmware updates for the rest of us that should fix the problem. Call Westinghouse to see if you can get updated.

Did you double check your connections with your AV cables. Otherwise you may want to try a new cable. Still make sure all connections are tight and secure and plugged into the right ports. If this doesn't work I would suggest call customer service for your DVD player.

It's posible your TV when into protection mode to prevent further parts from being damaged. This normally happens when a single parts goes bad inside your TV.
You may have to take it to a repair shop.

if you have cable tv try unplugging and plugging in that cable if that doesnt work you might have a bad cable. check for damage along the cord or bends in the metal ends sometimes that can also be the problem

I bought a 32 LCD Westinghouse TV 12 months ago. It stopped working so I brought it to a TV repair shop. They determined that the main board went out. The TV's power supply is working but there is no screen or sound, nothing. The TV repair shop had to call Westinghouse to inquire about a replacement part. Funny, Westinghouse doesn’t make replacement parts for this TV. Westinghouse said we need to ship it back to them and they will send us a new TV. Okay that sounds good but they wont pay the $100 plus shipping costs for us to ship the broken TV back to them. Also, they make you send them the TV before they send you the replacement TV. That can take days. If the customer's TV went out because of the company’s faulty product, the customer shouldn't have to dic around with this shipping issue – Waa, Waa! The TV was nice but for it to conk out in one-year shows what shi++y merchandise Westinghouse is selling their consumers. “Buyer Beware”