Mamiya 645 AFD II Stickers Inside Battery Compartment?

Hi everyone,

I recently bought a used Mamiya 645 AFD II from Japan, and I’ve been really happy with it so far. However, I just noticed something odd in the battery compartment: there are small stickers placed over some of the metal contact areas. I’ve marked them in blue in the attached image.

I’ve always used the camera with these stickers in place, and everything has worked fine—including the motor drive and metering. But I recently had a strange issue where the camera auto-advanced the entire roll without firing the shutter, and now I’m wondering if these stickers might be interfering with proper battery contact.

My question is:
Are these stickers supposed to be there for safety or shipping reasons, or should they be removed for normal operation?
If anyone has seen this before or knows whether they could cause voltage instability or misfires, I’d really appreciate your input.

Thanks in advance!
—Lukas

I expect these stickers are to prevent short-circuiting some of the cells if for some reason the battery holder makes contact with conductive items that manage to short some of the contacts. Not something that would typically happen in normal use, so I assume the stickers are there to hedge against a rare contingency.

The winding-through problem sounds like a bad contact involving a sensor/feeler somewhere that's involved in the film transport mechanism.

There are only 2 contact points at the ends of the horseshoe. There are 6 1.5 volt batteries in series, yielding 9 volts. Those "stickers" are some kind of epoxy and should be left in place. If they fall off, after all these cameras are getting old, put electrical tape over them. When I first got my 645 AFD the battery compartment had fallen apart. I glued it back together and it worked. Since I had no guidance it was lucky it only went together one way, but it was logical that the batteries would be in series.

The motor drive is built into the film back which has its own power supply but with a single button battery it doesn't appear to be enough power. It probably draws the power from the 9V.