first of all, You can ask an Pioneer DJ Support via Phone to get your UNIT Repaird, but you Need to tell him the "Long" Story of the unit and also that the warranty is passed.
I have Calld the Pioneer DJ Hotline years ago to Fix my wrong working DDJ T1.
They did that very fast but with warranty left.
They Told me on the Phone that "if they see any damages that could be from my self to the Unit they would Send me an Offer for Repair Coast n stuff.
I Would not Open the unit by my self to fix that.
If its helpfull see the exploding diagram of the Unit.