Hi so I got my car (2006 Skoda Octavia 2.0 diesel elegance retro fitted with a Columbus unit RNS510 (2010 model) back in 2019 and I changed the can gateway module with a 2013 skoda and had it coded by rustynuts Aka Andy on this forum. 
 

The unit stopped working months after so I have only just bought a new working unit. I unplugged the old one and I am planning to put the new one in as I want to sell the car. 
 

my question is as this car has a can gateway module for a 2013 And was previously coded in can I just plug the new unit in, it won’t drain my battery will it or do I need to have it recoded so it doesn’t, really hoping I don’t have to code it as I have a week to sell the car and don’t have a vcds code scanner just a minor handheld obd2 scanner. 
 

please help and answer if I need to scan and code or just plug and play.

I would imagine any OE Skoda replacement will need code trickery to unlock its security.

You might need the security code to get it to work, which if you don't have can be sourced from many eBay sellers by providing them with the unit's serial number and 10 or less of your English Pounds.

Module coding I know nothing of.