Cooling System

I have a 2002 Jetta Gl- 2.0 I want to drain the cooling system, but I do not have the manual. There is no petcock on the radiator that I can see. How do you drain the system so I can flush it and Put in new Coolant. I have 117,000 miles.

I also have a check engine light that has been on for 1 year. The diagnostic check says its the catalytic converter. How can i get the light to go off and stay off?

Thanks for your help.

In the 98 Jetta with 2.0, the Bentley indicates to remove the bottom radiator hose at the thermostat/waterpump housing. Sure is messy.