DualShock 4 D-Pad issue

I have a DualShock 4 controller that I’m working on and everything but the left right and up buttons work. The down button works fine. Any suggestions for how to proceed?

I don’t know if this answer will still do any good for you, but it might do for someone who comes here afterwards, so here we go.
You should replace the conductive film on those, as it is most likely the source of the problem. To be sincere, I don’t know if you can clean those with a swab and isopropyl alcohol (someone shout out to me if you can), but you will lose nothing by trying. If it still doesn’t work, don’t worry, the film is very very cheap, I bought one from Shopee for two dollars a couple weeks ago. I’m not sure how to post links here, so you just search on YouTube for “How to replace conductive film DS4” and you’ll see a video explaining it to you.

P.S.: Open your controller first and look for the type of conductive film it has, as different versions of DS4 may have different films. Only then you can buy a new one.

I’ve been encountering this issue several times and indeed the problem is on the conductive film for buttons. First of all you should check the trace on the the conductive film with magnifying glasses or microscope. If there’s any trace that gone replace the conductive film, if there’s none than you should check if there’s any corrosion on the connector part of the conductive film, If there any then clean with IPA but i need to remind you to brush it slow and softly because if you clean it with too much power then the trace could vanish. Now here’s the magic trick, if you look closely there should be some kind of pad in the DS4 case to push the connector from conductive film to the board, you need a cut tiny piece of tissue then attach it in the pad then install the conductive film. From my experience so far DS4 buttons not working is because there’s a few pin in the conductive film that didn’t touch the board and the tissue would compensate the pressure to push the pin to the board. Lastly tighten the screw and try it.
Hope it’s helpful