During reassembly, the face sensor cable can be tricky to connect. Follow these tips to connect the cable:

Thread your fingers through the eyepiece trim’s eyeholes and grasp the edges of the sensor cable.

Slide the sensor cable into the socket until the first set of tabs rests in the socket. This should flip the lock tab down partially.

Use a spudger to press the lock tab down towards the cable to lock it in place.