TV Boot Loop until 'warmed up'. Possibly bad connection
I have a UA32C6200 Samsung TV that I picked up cheap a while ago. It was working fine until I moved house a few months ago.
When I power it on, for about 5 minutes its stuck in a sort of boot loop where it does the Samsung jingle, clicks (relay click in the back somewhere), displays the screen with output for a second then cuts off with another relay click.
It repeats this a number of times until eventually it comes on and stays on as though its a loose connection that closes when it warms up.
Second to that when the screen does come on it has vaguely purplish vertical lines across the whole screen.
I did the obligatory tap on the top of the screen the first time it did this and the lines flashed away, further confirming my suspicion of some loose connection some where. I also found if I press on the back of the casing around top left which I believe is over the main circuitry the lines disappear and the screen works fine. Sometimes it stays sometimes it doesn't.
I have taken the back off and visually inspected things while it was powered. Initially it looks ok and the cables and connections all look to be solid with nothing particularly loose. I plan to do some more careful probing with a multi-meter on some of the components to check them.
My question then is this. Is there a common component on Samsung panels that would cause this behavior?
If anyone has any useful thoughts that might save me some time it would be hugely appreciated.
I don't have high hopes of being able to fix this screen as it is quite old and way past its warranty. Its useful as a spare screen in the garage/office where ever I use it. Its nice as its very slim and fits really flush against the wall, and I have a penchant for fixing things myself and I'm quite capable with a soldering iron so thought I would attempt a DIY repair before I send this thing to TV heaven.
Update:
Thanks @oldturkey03 I’m trying to get to those menus but it’s stuck in its boot loop again so will keep trying. On top of that I’ve a couple of Samsung remotes and can’t remember for the life of my which is the right one for this particular screen 🤦.
Here’s a couple of images I managed to get though:
The first is the purpleness. It’s quite hard to capture in a picture but it’s made up for vertical lines across the screen. The second image is after I’ve pressed the back as mentioned before, where it comes right and works as expected (ignore the green text behind it that’s from the source it’s currently connected to).
Update Two:
Back of the display:
Power supply:
Input/Output Control board?:
Display Driver?:
I believe this is the location where I am pushing down that affects it:
I have disconnected the cable from the power board labelled CMN801 (This seems to match your description of CMN802). This connects to the control board.
When doing so and connecting power there doesn't appear to be a way to turn on the screen at all. The backlight doesn't come on.
However, if I press the control board lightly where I point out when the screen comes on. It doesn't seem to be getting stuck in the boot loop... suggesting the loop is being caused by some communication issue between power and control.
I've still not been able to get into the service menu to perform those other tasks.