Entering service mode on LG plasma & LCD's

[Old Buzzard]

I am working on a few different LG tv's and would like to know if there is a way to enter the sevice mode when they won't power on,just blinking lights. I repaired a Sharp 60" and was able to enter the service screen by pressing the vol+ and the channel- then plugging the power cord in. I was wondering if LG has the same feature or not? I haven't been able to find anything like this yet. The tv's I'm working on are as follows; LG 60PA6550-UM,LG 60LS5750-UB, LG 50PC3D-UD,and LG 50PG20-UA. Any help would be greatfull.

[selldoor]

Re: Entering service mode on LG plasma & LCD's

Might sound a daft question but what good would it do entering service mode if you cant see anything on the screen?