I have a JVC 27'' AV-27530 TV that the picture is very dark

On most , it is adjusted on the G2 control

marked "screen" on the Flyback Transformer

http://tv.manualsonline.com/manuals/mfg/jvc/jvc_av_27530_av27530.html?idRes=1557877

this is the link to your television manuals it consists of troubleshooting regarding color screen problems.. hope this help you

In many many cases this is an indication of a failing picture tube. The gun assembly in the neck of the picture tube is shorting. There is a fix, but this is surely last resort and the final cure may not provide a fix. Picture tube rejuvenation is not always successful. I would certainly opt for a new TV. Thanks for asking, and show a few hands of support!

I have the AV-27S33 model and in the rear to the right of the inputs are two slits and inside these slits are two screws. The top screw is the focus,the bottom the brightness.Your tv is a different model but it may have this same adjustment,if it does try turning the bottom screw to the right to increase the brightness.

Put it in the custom mode.Put the contrast to the max.Put every things in middles may be colors for less.Now u have the desire ajustment u want?

My jvc 27" tv was so dark I could hardly see any night scenes, even with the bright all the way on. If you push the sleep button, let go, then hold down the video and display (together), the service menu will come on. Scroll down to #7 (too dark) and adjust the brightness there. Works immediately. Good luck.

How many years is your TV now? Usually TV has its life span, there comes a time that it happens. And need to look for a technicians, cause some of theme can still be repair by adjusting the brightness inside your TV.

**WORKS**

In my case, the adjustment was available from outside the TV. Sortof. On the rear of the TVabout 2 inches to the right of the coax in, there are two vertical slits on a little protrusion. Inside the slits are the two adjustment screws. The lower screw adjusts brightness, the upper screw adjusts focus.

Yes you could look for the capacitor that is leaky, probably in the 200v line, or you could just open back and turn up G2 screen control on the Flyback. You have Screen and Focus on this black transformer with a long anode lead going to the picture tube of set. Becareful, High Voltage!

This sudden changes in brightness are caused by the change in voltage inside the tv,not in the outlet in the wall but inside the set,The changes are an indication something is going wrong and it needs to be corrected,the set does have a brightness limiter but it only works when the set wants to get brighter than normal,You need the assitance of a servicer to correct this problem.