My Ultegra Di2 just arrived today, bought on AliExpress. The shifters don’t turn on at all — I even replaced the batteries just to be sure. I’m starting to suspect these might not be the wireless ST-R8170 levers they were advertised as. The internal mechanism also looks different, more like a mechanical unit. If anyone has experience with this or can tell me more from the photos, I’d appreciate it. I’m also open to any tricks or checks I might try to get them working.