Light My Bricks: LEGO Mercedes Benz Arocs 42043 Lighting Kit


The following page is the instructions for the Light My Bricks LEGO Mercedes-Benz Arocs (42043) LED light kit.

To ensure a trouble-free installation of your light kit, please read and follow each step carefully.

If you run into any issues, please refer to the online troubleshooting guide.

To download this instructions guide in PDF format please click here.

Please note: This page lists instructions for the LED light kit only. If you are wishing to purchase the Light My Bricks LEGO Mercedes-Benz Arocs (42043) LED light kit , please click here to view the product page


Package Contents:

  • 18x White 15cm Bit Lights
  • 2x Flashing White 15cm Bit Lights
  • 2x White 30cm Bit Lights
  • 2x Rotating 30cm Bit Lights
  • 4x 8-Port Expansion Boards
  • 1x 5cm Connecting Cables
  • 1x 15cm Connecting Cables
  • 1x 50cm Connecting Cable
  • 8x Adhesive Squares
  • 1x Power Functions Cable

LEGO Pieces:

  • 6x Trans Clear Round Plate 1×1
  • 4x Trans Orange Round Plate 1×1
  • 2x Trans Red Round Plate 1×1

Important things to note:

Laying cables in between and underneath bricks

Cables can fit in between and underneath LEGO® bricks, plates, and tiles providing they are laid correctly between the LEGO® studs. Do NOT forcefully join LEGO® together around cables; instead ensure they are laying comfortably in between each stud.




CAUTION: Forcing LEGO® to connect over a cable can result in damaging the cable and light.

Connecting cable connectors to Expansion Boards

Take extra care when inserting connectors to ports of Expansion Boards. Connectors can be inserted only one way. With the expansion board facing up, look for the soldered “=” symbol on the left side of the port. The connector side with the wires exposed should be facing toward the soldered “=” symbol as you insert into the port. If a plug won’t fit easily into a port connector, do not force it.



Incorrectly inserting the connector can can result in bent pins inside the port or possible overheating of the expansion board when connected.

Connecting cable connectors to Strip Lights

Take extra care when inserting connectors to ports on the Strip Lights. Connectors can be inserted only one way. With the Strip Light facing up, ensure the side of the connector with the wires exposed is facing down. If a plug won’t fit easily into a port connector, don’t force it. Doing so will damage the plug and the connector.



Installing Bit Lights under LEGO® bricks and plates.

When installing Bit Lights under LEGO® pieces, ensure they are placed the correct way up (Yellow LED component exposed). You can either place them directly on top of LEGO® studs or in between.






OK, Let’s Begin!

1.) Start by disconnecting the head light pieces as well as surrounding pieces as per below.









2.) Starting with the left side of the truck, carefully split the section as per below by creating a gap in between sections, then take a White 15cm Bit Light and thread the connector side of the cable through the gap we have created.




Thread the cable all the way through until the LED component is up against the edge on the left of the black stud. Reconnect the following LEGO section ensuring the Bit Light is right up against Trans Orange Plate, then reconnect sections to close up the gap and secure the light in place.




3.) Repeat previous step to install another White 15cm Bit Light to the right side







Pull both cables out from underneath


4.) Take the following two pieces and remove the trans clear tiles from each side.



Take a White 15cm Bit Light and place it over one of the pieces over the light grey stud. Secure the Bit Light in place by connecting a provided Trans Clear Round Plate 1×1.



Repeat this process to install another White 15cm Bit Light to the other piece using another provided Trans Clear Round Plate 1×1


5.) Take one of the pieces and then recreate the same gap we created in step 2 to allow us to thread the cable through the left side of the truck. Thread it all the way through and then reconnect this section over the black stud as per below:





Close up the gap.


Repeat this process to reconnect the other piece to the right side.





6.) Take the two headlight pieces and then disconnect the trans clear 2×2 plates.



Take 4x White 15cm Bit Lights and then place each one over each hole of the light grey round 2×2 plate as per below:


Reconnect the trans clear 2×2 plate over the top to secure the bit lights in place.


Turn the headlight section over and then group the four cables together and then twist them around each other to form one large cable.





Repeat this process to install another 4x White 15cm Bit Lights to the other headlight section.


7.) Take one of the headlight cables and then thread it through the following gap on the right side of the truck. Thread it all the way through and then pull it out from underneath. Reconnect the headlight to original position.




Repeat this process to reconnect the headlight on the left side of the truck.




8.) Take 2x 8-Port Expansion Boards and connect them together using a 5cm Connecting Cable. Connect the cable to the end ports.


Connect all six Bit Light cables from the left side of the truck to one of the expansion boards and then connect all six Bit Light cables from the right side of the truck to the other expansion board.



9.) Test the lights we have installed so far are working OK by taking out the LEGO Power Functions Cable and connecting it to a spare port on the expansion board. Connect the other side to your Power Functions Battery Pack and then turn on to verify all is working OK.





Disconnect the Power Functions Cable from the expansion board and proceed to the next step.


10.) Disconnect the trans orange round tiles from both sides of the truck.




Take a Flashing White 15cm Bit Light and thread the connector side of the cable through the hole where you disconnected the trans orange round tile from. Thread the cable all the way through until the Bit Light is sitting right against the edge of the hole.



Press the Bit Light down so that it sits flat against the edge and the secure it in place by connecting a provided Trans Orange Round Plate 1×1 over the top.



11.) Repeat previous step to install another Flashing White 15cm Bit Light to the left side of the truck using another provided Trans Orange Round Plate 1×1






12.) Turn the truck on it’s side so we can access underneath of it and then pull down both cables from the two Bit Lights we just installed.


Take another 8-Port Expansion Board and connect both lights to the first two ports.



13.) We will now install lights over the top front of the truck. First disconnect the trans clear round tiles from each side.




Starting with the left side, seperate the following sections by pulling the front piece forward.


Take a White 30cm Bit Light and thread the connector side through the following hole and then in between white and black sections as per below:



Pull the cable all the way back and then thread it through the second hole of the white piece as per below and then down in between black and grey sections:





Press the Bit Light flat against the edge of the light grey piece and then secure it in place by connecting a provided Trans Clear Round Plate 1×1 over the top.



Close up all the sections we separated.


14.) Pull the cable down the back and then thread down through the following space. Pull it down from underneath (above the wheel) and then connect it to the third port along the 8-port Expansion Board from step 12.





15.) Repeat steps 13 to install another White 30cm Bit Light to the top right front of the truck using another Trans Clear Round Plate 1×1.










16.) Pull the cable back and then pull it down over the back white section as per below then thread the cable down through the following space. Pull it down from underneath (above the wheel) and then turn the truck over so that we can bring the 8-port Expansion Board from step 12 across. Connect the Bit Light to the next port along this expansion board.








17.) Take a 15cm Connecting Cable and connect it to the remaining port on one of the 8-port expansion boards from step 8.


Thread the other end of the 15cm connecting cable through the following space (over the light grey piece) and then connect it to the next port along the 8-port expansion board (from step 12)



18.) Take 4x Adhesive Squares and stick two on each 8-port expansion board at the front. Mount the two expansion boards underneath the truck in the below positions.




19.) Neaten up excess cable from the Bit Lights at the front by pulling them all the way out and then twisting them around each other and then tucking them up the sections closest to each expansion board.







20.) Connect the Power Functions Cable to the Power Functions Battery pack and then pull the cable over the back and then thread it down the space below the cream coloured cog wheel. Pull it down from underneath the truck and then turn the truck on it’s side to allow you to connect the power functions cable to a spare port on the 8-port expansion board.





Turn on the power functions battery pack again to test all the lights are working OK.



21.) We will now install our Rotating Bit Lights inside the two beacons. First disconnect both beacon light sections and then disconnect the black round plates 2×2 from underneath each.





22.) Take 1x Rotating 30cm Bit Light and place the component upside down (flat side up) over the top of the middle of the trans orange round brick 2×2. Reconnect the black round plate 2×2 directly over the top then flip the beacon over to the correct side.





Repeat this process to install another Rotating 30cm Bit Light to the other beacon.


23.) Reconnect both beacons to the top of the truck ensuring the cables are facing toward the back. Because we have installed Rotating Bit Lights inside trans orange round brick, we will not be able to push this brick all the way down the technic pin.

Ensure that you do NOT forcefully push the Beacon all the way down otherwise this may damage the Rotating Bit Light


The base of the Rotating Bit Light should be sitting on top of the technic bar coming up from underneath

Take the left beacon cable and thread it down the following space:



Pull it out from underneath and then thread it through the space below. Pull it out from underneath the truck.



Take the right beacon light and thread it down the following space:


Pull it down from underneath and then thread it down through the next space below:




24.) Turn the truck over and pull both beacon light cables out from underneath and connect them to the two remaining ports on the 8-port expansion board.



Turn the truck back to its correct side up and then Turn ‘ON’ the Power Functions Battery Pack to test the Rotating Bit Lights are working OK


25.) Turn the Truck back over and then mount the 8-port Expansion Board underneath in the following position using 2x Adhesive Squares.



Neaten up excess cable from all the Bit Lights by pulling them all the way out and then twisting them around each other and then tucking them up one of the spaces closest to the expansion board.




26.) Take a 50cm Connecting Cable and connect it to the remaining port on the 8-port Expansion Board at the front of the truck.



Follow the below images to thread the other end of the cable through towards the back underneath the truck through the following holes and gaps.








27.) Connect the other end of the 50cm Connecting Cable to the first port on the remaining 8-Port Expansion Board.



28.) Turn the truck over to the back and then remove the three trans coloured round tiles (orange, red, clear) from each side.





We will installing another 6x White 15cm Bit Lights and replacing the round tiles with the provided trans coloured plates.



29.) Take the first White 15cm Bit Light and thread it through the first hole on the left side. Thread it all the way through and then push the Bit Light flat down against the edge of the technic pin before securing it in place with one Trans Orange Round Plate 1×1.






Using the same method, install another 2x White 15cm Bit Lights for the left side of the truck using a provided Trans Red Round Plate 1×1 and Trans Clear Round Plate 1×1 to secure them in place.





30.) Take the three cables from the left side and then twist them around each other to form one large cable.




Thread the cable up through the following space underneath and then pull it all the way out from the back as per below






31.) Repeat previous steps to install another 3x White 15cm Bit Lights to the right side of the truck using the remaining provided trans coloured round plates 1×1





32.) Thread the cable up through the following space underneath and then pull it all the way out the left side (same with the left side cable). Then bring all cables together and pull them down behind the wheel.





33.) Turn the truck over and then connect all six lights to the 8-port Expansion Board.




34.) Remove the back left wheel and then disconnect the 50cm connecting cable from the expansion board and thread the expansion board through the following space. Then pull it over the wheel axle and reconnect the 50cm connecting cable



Mount the expansion board to the side frame in the following position using another 2x Adhesive Squares.



Pull the excess cable from the two sides back and them twist them around each other to secure them from dangling down and being seen from the back of the truck. Tuck them in close the expansion board.






35.) Eliminate excess cable from the 50cm connecting cable by pulling it back towards the back expansion board and then twisting any remaining cable around the the six bit light cables as per below




36.) Reconnect the back wheel and then turn ON the power pack to confirm the back lights are working OK.




This finally completes installation of the Mercedes Benz Arocs Light Kit. We hope you enjoy your light kit.

We Thank YOU for purchasing this Light Kit!