After surviving the attack by the Prototype on the Safe Haven, Doey has gone mission in action in Poppy Playtime Chapter 4. However, the plan to set up explosives in the Foundation cannot wait, and Poppy sends the players off on their mission. On your way to the Foundation, you'll need to solve another Cogwheel puzzle to open the locked door and enter the mines area. It's a little trickier than the generator one. Here's how you can solve it.