G85
 

After taking the bottom ball joint off to replace a front cv joint boot, not touched the rack, I have the code 00778 g85 & my steering wheel is off at about 7-8 oclock when going straight, any ideas how I manged this, like i said I never touched track rod ends, Thanks

you need to get an alignment because the ball joint was loosened. as for the code,

clear it, see if it comes back. if it does. clear it again then go to output tests, or basic settings to enter the module in adaptation mode. turn wheel 1 full turn to the right, then 1 full turn to the left. then drive car under 13kmh and turn wheel 1 full turn to right and 1 full turn to left.