Before we start - check you have everything you need.

​These sets come with the following parts:

  • 8 x 30cm White Bit Lights
  • 4 x 15cm White Bit Lights
  • 3 x White Strip Lights
  • 4 x 5cm Connecting Cables
  • 1 x 50cm Connecting Cable
  • 1 x 12-Port Expansion Board
  • 1 x 8-Port Expansion Board
  • 1 x 2-Port Expansion Board
  • 8 x LEGO® 1x1 Round Plates (studs) in Trans Clear

And either:

  • 1 x AA Battery Pack
  • 1 x USB Adaptor

​And of course you'll need LEGO® set 21037 - The LEGO House!


OK - here's how it looks when you've finished building this model...


First let's remove the roof module and set it aside.  We'll do that bit later.

The flip the model upside down - we need to get some power into the body of the building.

Carefully break off a section of the rear base plate - it doesn't matter too much which black plates come off but get that 4x12 DBG plate off!

Take the 50cm connecting cable and connect the 8 port expansion board to the end.  Feed that end into the house through the base. 

Flip it over and make sure you have a little slack - the 8 port board should sit happily in the middle of the floor with enough cable so you can lift it by a cm or two to make wiring easy.

Then replace that base piece, making sure the cable goes between the studs.

Here's the cable coming out neatly from the rear of the model now:

 Now we're going to add the first three 15cm White Bit Lights.  They're numbered 1, 2 and 3 here:

Bit Light 1

Carefully lift off the dark green and pale yellow building modules as shown.

Then grab the staircase block by the front and back and lift.  This will 

Reveal the Light Bluish Grey 1x4 plate which will get our first light.

Place the Bit Light facing up between the two centre studs and reassemble as shown.

The replace the 1x4 and carefully fit the Yellow staircase module back into place, trapping the cable between the studs.

Replace the Dark Green and Pale Yellow roof blocks and we move onto number 2!

Bit Light 2

Carefully lift off the bright orange module at the front left of the model. When you lift it remember one piece underneath won't lift up because it's stuck to the lower building!

Flip it over and remove the white 1x4 and the clear-trans 1x1.  Add the 15cm White Bit Light where the clear-trans 1x1 was and replace that piece.  It should now look as shown:

Replace the white 1x4 and carefully put this module back onto the model.

Bit Light 3

Lift off the Dark Red roof module at the front-right of the model.

This one is a beauty with a helpful clear-trans 2x2 brick in the centre!  Dismantle this as shown here:

Insert a 15cm White Bit Light through the gap at the bottom and position it in the middle:

Strip Lights

This step is pretty straightforward and there's not much accuracy needed.  Simply remove the adhesive tape backing on the three strip lights and poke them into the ground floor rooms as shown here. 

You may find it easier to attach a single 5cm connecting cable to each before you start sticking them down.

Test it!

Let's take a break and wire up the three Strip Lights and three Bit Lights to our 8 port expansion board.  Connect your power supply (Battery or USB) to the 50cm cable sticking out the rear, using the 2 Port Expansion Board to connect the cables. And turn on the power.

Hopefully at this point you'll see the rooms lit up nicely.  If not go back to basics and troubleshoot one light at a time.

If you find nothing works and the battery starts getting hot then cut power - there must be a short circuit.  This can happen due to a trapped wire being squeezed too tightly between bricks, or occasionally from a faulty expansion board.  Check our Troubleshooting Guide for advice on this.

The Roof Module

Setting aside the  main Lego model now, it's time to fit 9 separate lights into that little roof module!

First off an easy one - at the front of the module is a single 2x1 tile in trans clear. 

Pop that off and use the last 15cm White Bit Light between the studs.  Replace the tile on top and run the cable neatly out to the front.

Leave this for now - we'll connect it up later.

The 2x4 Brick on the Roof

And for the finale - let's tackle that amazing signature brick on the roof.

Reach in and lift out the piece with the trans-clear tiles on each stud.  You may find a brick separator helps get this out.

Here's how it looks:



 As you can see, each 'stud' is actually a clear-trans tile fitted to a 1x1 white square plate.

We need to replace all eight of those 1x1 white square plates with the supplied 1x1 Clear-Trans Round Plates.

We could have used square pieces here but the round shape proved easier to run the cables.

 To fit the eight lights, assemble as follows:

White Base Plate > Bit Light > Clear Trans 1x1 Round stud > Clear Trans 1x1 Round Tile.


 Once you have fitted all eight lights, wrap the wires underneath the module and then wrap them together to form a nice neat braid.  This will make the plumbing easier later!

 To fit the lights we need one small adjustment.  Take the 'cradle' which holds these lights and remove the 3x1 White Plate at the back where the 4x1 Plate with Upright is fitted.

With this gone there's a little more wriggle-room for the wiring.

Now we need to fit the lighting block down to the base, and get that 4x1 back piece in as well.  It's a bit of a fiddly operation - get the light block roughly in place, then fold the cables down at the back, and then slot the 4x1 back piece in.  When done it should look like this:

Be prepared for a few of the clear-trans caps to pop off as you go!  Keep wiggling and applying pressure and you will get it looking neat and straight again.  It's worth taking your time over this part as it's the most visible part of the model.

Wire it all up!

Hold onto your hats we're almost done.

Place the brick module back onto the roof and run the wire neatly out the rear between the Blue and Green roof sections:

Then take all 9 wires (8 from the back and 1 from the front) and twist them together neatly underneath that roof module.  Connect all 9 wires to the 12 port Expansion Board and then use the last 5cm Connecting Cable to join the 12 Port Expansion Board to the 8 Port board inside the house.

Carefully replace the roof module gently pushing any errant cables back inside and out of the way.

Sit back.  Breathe.  And hit the On button.

Wiring Diagram

To help you see how it works - here's how it all connects together.  We've broken this down into three main sections : components outside the model (i.e. behind it and out of sight); components inside the main body of the building, and those bits which go into the removable roof module.

End Result

And here we are - this is what you should have at the end! 

For ​more images and guidance check out our blog post on this project!

Questions / Comments / Need help?

Check out our User Guide and Troubleshooting sections. 

Or get in touch - we're always happy to help.