What part needed for fixing DS Lite? Will not draw a straight line

blue_monkey_2

We have a few DS lites of the same age and all seem to be acting up.

Say we mark a straight line it will veer off quite severly to the left then comes back to the straight line at the bottom of the line (IYFWIM) so while I'd dearly love to get DD that new drawing game, right now there is no point.

What part do I need to replace it. I have seen spare screens on eBay but not sure if it is the screen that I need as it is not cracked or broken. And would screen protectors stop this happening again in the future?

Thanks

gaming_guy

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blue_monkey_2

OK, no that did not work. I have tried drawing some circles and the line veers off fo you get an odd shape, but the line does not follow the pen at all.