Mine had this issue. Try attaching the seat. When I did, all lights lit up but the one to say the yellow legs were attached is red. I believe it may be a broken wire or similar, as it openly happens when the seat is attached, otherwise no lights whatsover and the seat is clipped in. I can hang offi it without it coming out. If anyone has any idea how these come apart I would be great. I have taken out the 6 obvious screws andRemoved the 2 that hold the top cover which allows me to prise open the frobut can not see how the rear of the unit comes apart.