solved!! So. This happened to me.. my controller would flash yellow once then not respond again unless plugged in or reset. Then once again one flash then nothing...

It ended up being a faulty conductive film that stopped working properly. Here is how you can easily find and fix this problem..

Solved this by looking at forums and adding different solutions together.

First off plug the controller into a PC. Once it has installed go into control panel -> hardware and sound -> printers and devices -> RIGHT click 'wireless controller' -> select 'Game controller settings'. -> select 'Properties' -> make sure your in the 'TEST' tab up the top.

From there TEST ALL YOUR BUTTONS.

I found my PS button (that turns the controller on) was faulty!!! It did not show up as to it working when pressing that button but all other buttons worked...

So I went into ebay and bought the 'conductive film for ps4 buttons controller' .. for $3

Waited in post took apart my controller changed films and bingo!! Works perfectly fine.

If any other buttons are faulty it will show up on that test page. MAKE SURE YOUR USING THE RIGHT CABLE. Some cables don't transfer properly. So just keep changing cables if the pc is not picking up the controller (or change USB ports).

Hope this helps as it took a while to find all this.

Good luck!