Help with CTM644 Monitor

[RetroAsh1978]

Hello everyone. I was wondering if someone could assist please.

I have bought a very nice condition CTM644 and being working for a few days and now its just shows a horizontal bright line when I turn on my Amstrad, nothing when off. This happened out of the blue with no noises or warning.

I read this could be vertical collapse. I do have a spare working CMT644 mainboard which I could swap but I would like to try and fix it.

Any help would be appreciated as it was a beautiful picture.

CTM644

Mainboard

Thankyou

[Bryce]

Hi,
    it's highly likely that one or more electrolytic capacitors decided to "retire". I would recommend you (or someone who knows how to if you don't) to replace the those caps. It's quite a bit of work to remove the main PCB, so you may as well replace them all while the board is out.

Bryce.

[roy bates]

that is vertical collapse

its either no power to the vertical section,or ,vertical ic failed(most common)
if its capacitor,its shorted and probably took out the power rail before it,thats from experience

this is comming from someone who repairs monitors and tv's for the last 35 years

and yes,i have worked on these and still do

[martins]

Thanks Roy - from your experience, on a working monitor, is it worth replacing any/all of the caps to prevent future damage, or only worth doing when one of them fails?

[roy bates]

thats up to you,i dont usually unless they are bad during a repair

[martins]

Thanks very much

[darkhalf]

I've had to fix up a couple of mine, and all the ESRs on the caps measured fine. So I would personally only replace what is needed. 

Check the capacitors in question for shorts first. If the power section is gone, the components it takes out can very (see my other posts on here about CTMs)