How to open a trapdoor in the Dump on Dumptruck quest in Borderlands 3? Borderlands 3 guide, walkthrough

Last update: 16 September 2019

On this page of our guide to Borderlands 3, we explain the potential problem with opening a trapdoor in the "Dump on Dumptruck" quest. This is one of the first optional missions. To release the trapdoor you need to complete a small environmental puzzle and its solution can be found below.

The riddle is solved immediately after dealing with The Holy Dumptruck mini-boss. Once you get to the secret door you will find that the entrance is closed.

Turn around and start following the yellow cable. Get to the place where the cable is broken. Look up and shoot the large shield (image above) with any weapon. This will cause the water to start flowing.

Now aim at the smaller shield shown in the attached image. Hitting it will restore power supply.

You can already return to the secret door, which opened thanks to power flowing to the fuse box. Jump into the shaft to find yourself in The Holy Dumptruck's hideout.