ICowie
A2OC Donor
Had this a couple of times. The ABS gets confused due to the lack of signal from the brake switch. The replacement brake switch should function as normally i.e. pedal pressed all 3 brake lights on, pedal released all 3 brake lights off. The issue is the ABS pump performs 2 tasks and currently can not tell which mode it should be in. It either works in braking mode when the pedal is pressed, but if the pedal isn't pressed it swaps to traction control or ASR mode. The car needs to move so the ABS sensors and the brake light switch can reset it. Worked for me every time. Unless you are "lucky" and there is a different fault. Have you set up the switch ( most now auto adjust ) but if it came with installation instructions did you follow them.
It could be this as I've never moved the car just plugged it in and tried the brake to see if the lights worked or not. There wasn't any instructions with it (Intermotor brand) that was the only new one I could find online, genuine one were all used items. I just jammed the brake pedal and relocated back into the holder.