Where the "aftermarket lights" halogen (aka not xenon/HID?) I ask because xenon/HID lights requires that the lowbeam "cold check" be coded off since there isn't an actual bulb (halogen or incandescent) that would provide continuity during the cold check. Thus, if you install xenon/HID headlights...low beam cold check should be coded off...this will prevent the warning to CHECK LOW BEAMS when you have installed xenon/HID headlamps.
{see the last sentence in the 1st paragraph under BULB MONITORING in the image below}
