I own a 320D E91 and I need guidance with my electric tow bar hitch and the problem CODE 423. I am unable to retract the tow bar, and the switch in the trunk is not showing any LED indicators or flashing lights. I have inspected the three fuses specified in the fuse box located beneath the glove box, and they all seem to be in good condition. Are there any further fuses or a module related to the tow bar that I may have missed? I am utterly bewildered.