what is the plastic film behind the instrument cluster?

[dezdud]

I took out my instrument cluster yesterday because of all these problems i'd been having with the fuel gauge moving with the left turn signal on. while it was still pluged in, but out of the dash, now when i do the turn signal, the gas gauge doesnt move with the turn signals, and now my green indicator turn signal lights work..?? wth? so i unplugged the cluster from the feed harness and am looking at it. theres this thin plastic circuit board looking thingy. and the harness just folds it over when you push it into the socket. Is that how it's supposed to be? is that stock? Looks cheesy as all heck.???