I’ve spent most of the day installing a Pioneer double din unit and connects 2 kit. Everything was tested and it was all ok. I proceeded to sort the cabling at the rear and clip the fascia unit in place. Once this was done and the power turned on there was no longer any power to the Pioneer or the cars time/ aircon display. Removed the unit and unplugged the cables etc but still no luck. Plugged the oem head unit back in and it all worked. Tried it again and now the oem won’t work. Fuse 35 looks ok and not blown. Any help???