Showing black screen with a blue line

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/
Line, faults & possible causes to LCD screen are given with illustrations. You can get an idea about the fault to an extent.

Vertical scan section circuit fault. Check and replace damaged component/s at its vertical scan output section circuit. If you wish to get some details, check the site linked here. Pull up older posts. Check the site in 'Mosaic' view. It will make search easy. http://electronicshelponline.blogspot.com/

There is a voltage loss in the main board. It will be best to contact any experienced service technician, as the work is a skilled one.

We used to say have a short service on the patio and buy a new set---damaged panel display unit is more than set cost (if it is even available)
Let it go---when damaged it can instantly damage other boards/parts in the set.

Run a car with no oil and see what happens........

LCD's use a colorful crystal see through display which only visible when light is shining through it. if you have sound and no picture it's always a faulty PSU. Very easy to change out actually.

Which caps on which boards as that sounds like a issue with the signal and FMT PCB. The v26 chassis like yours has problems with bad caps on the DM, Signal, FMT and the PWB and terminal

'I to am getting only wavy blue lines, no sound, doesn't even show channel indicators. TV was off for 4 days, came home turned it on and ten minutes later this screen appeared, it wont even show the menu screen, different channels or video inputs no sound either.

civilman, the first set has either no high voltage or is collapsed vertically, until someone checks for high voltage there is no concrete answer, the AV27730 is vertical collapse from your description, either the voltage to the vertical IC is missing or the vertical IC has failed, not a big deal cost-wise, hope this answers your questions, if not e-mail me back, good luck, BMW Rider

westinghouse_w32701_27_in_hdtv_lcd
power on no picture good sound and channel page up and down works
on background u can see dark picture

Sounds like, you have a bad optical block. Part can cost $550 to $800 + labor