A sudden Sanyo EZ20 monitor issue on a DK cab

[ckong]

A few minutes ago I was enjoying a nice game on my newly restored DK cab when suddenly out of nowhere in the middle of gameplay the screen went black with a very small very bright vertical line in the center of the monitor!!! 

I was shocked, and in the second or so that took me to turn off the cab I still could hear the gameplay sounds. I waited a few minutes, and turned the cab on again. I could hear the game startup normally, but the monitor came on black with the same vertically centered bright line. Shutted it down immeduately again.

I did not investigate yet what could be wrong, but what could be wrong? 

[ckong]

Thanks to the help of Level42 I now now the monitor has a vertical collapse issue. He pointed me to  atopic on this forum where I found some documents (flowchart and EZ20 trouble shooting guide) which will help me to solve this.

First thing which I have to do is to check and maybe replace TR402 and TR403 and according to the EZ20 trouble shooting guide maybe also TR401 and D401 and D403. I am electrical/technical a pretty noob, so I have a few questions about these parts:
- where stands D for? (diode?)
- where are all these parts located on the chassis (a picture would be nice)?
- how are these parts technical described (parts name and perhaps number), so that I ask the right parts in an electronics shop?