- drain coolant (remove hose from pump. Remove nsf under tray to access) iirc there is also a drain bolt on the chargecooler radiator.
- refill
- the most important step - when the chargecooler appears full, start engine & blip the throttle. This will turn on the pump for 30 seconds & pull the level down. Quickly Refill it back up to max during this period & screw the cap back on. Do this & you will never get a low level code 54.
This needs to be done on a stone cold engine, preferably a few days after you filled the system & have driven around a bit to ensure there are no air pockets.