Instructions on how to clean Joy-Con rail contacts.
What you will need
• Squeeze blower or compressed air can.
• 70% IPA (Isopropyl Alcohol). If you can't find 70%, dilute with water.
• Soft cleaning brush (Q-tips might also work).
* ESD safe brush is optimal.
Detach the Joy-Cons from the Switch tablet.
Turn off the Joy-con by pressing the pairing button once.
Look for the contact pins on the Joy-con's rails and Switch's rails. (Pictures below)
• Use your squeeze blower/compressed air can to blow into the contacts.
• Apply some IPA to your cleaning brush, then brush it gently on the contacts, use just enough force for dirt and grime to be dislodged.
• Wait 30 seconds for the IPA to dry out.
• Slide the Joy-Cons into the respective rail.
∞ Note: Look under the arrows on the Joy-con's rail to find the contacts. The contacts on the tablet's rail are at the respective location to align to the Joy-con's rail's contacts.