How to Replace the Main Electronics Board (UM2/+)

Changing an electronics board in your machine might seem a bit daunting at first. Although the instructions are very specific and need to be followed exactly, they are straightforward and require no previous knowledge. Please read each step completely before beginning. These instructions apply to the Ultimaker 2, 2 Extended, 2+, and 2+ Extended. The 2Go is similar, but has a different cover and is oriented differently. You can find instructions for changing the electronics in a 2Go here.

Tools Needed: 

  • 2mm allen key (the middle-size from your accessory bag) or hex-head Screwdriver
  • Pliers or 5.5mm nut driver
  • Small flat head screw driver

1. You will first need to remove the L-shaped cover that sits in the back left corner inside your printer. It is held on with two screws. One screw is on the left panel (below the screws that hold the motor on). The other screw is on the back panel (approximately three inches above the on/off switch). Remove the cover while the bed is down to avoid damaging the cover or panels. 

2. In order to get to the remaining screws, you will need to raise the bed. There are two ways to manually raise the bed. You can pull up on the bed with fingers under each side of the bottom silver plate, or you can twist the screw at the back. 

3. Unplug your printer and carefully lay it on its back. You may want to lay it on a piece of clean cardboard or a soft cloth to avoid scratching the panel. Laying the printer on its back will not damage the standard feeder. If you have a modified feeder, you will want to lay it on its left side instead.

4. To access the board, you have to remove the cover located on the bottom of your printer. The screws for the cover go down through the bottom panel and are secured with lock nuts. You will need to hold the nuts still using the pliers or the nut driver. Do not unscrew the board yet. You will see a black rectangle (ferrite core) secured around some of the wires on the left side. One side will have a latch that pops into place. Open the ferrite core and place it off to the side. We will need that again later.

Depending on when your printer was made, some UM2 printers will have an extra wire; it should be brown and red. When removing the cover, you'll notice it isn't plugged into anything; this is normal. This wire was included as an extra for potential modifications the user may choose to make. Leave it unplugged.

5. Some of the wires are easier to remove from the board while it is still secured to the bottom panel. Some are easier to remove after the board is detached. Let's start at the top left corner (if your printer is on its back).

The top two connections are labeled EXP2 and EXP1. One at a time, remove the wires from both of these ports by pulling on the flat cables. The cables themselves should be labeled 1 and 2. If they are not, do so before moving on. The next connections with wires are labeled TEMP 3 and TEMP 1. We will do those after we take the board off. The next three connections are labeled Z-STOP, Y-STOP, and X-STOP. Each connector has two wires that should be treated as a unit. Unplug each one. For now we will skip SAFETY2, SAFETY1, LED PWM, and FAN PWM. 

Let's move on to the right side. These wires go to the motors. All four motors have the same color cords. You may want to label (on the white part of the connectors) which is which as you unplug them. Don't worry if you forget, we can figure out which cord corresponds to which motor by tracing where they come from when we reconnect the cords later. Remove the wires from E1, Z, Y, and, X. Each connector has four wires (one of each color) in it. Those four should be treated as a unit and not as separate connections. We will skip HEATED BED and HEATER1 for now.

6. Now it is time to remove the board from the bottom panel. There are four screws that go down through the bottom panel to secure the board. There are no nuts on the underside for you to hold. Unscrew all four screws. Each screw has a black spacer between the panel and the board. Collect these and set them off to the side. We will need them when we put the board back together. Set the board so it is post-side up with the green blocks on the right and the power switch opposite you. 

7. Now we'll remove the remaining wires. We will again begin on the top left. Gently lift the tab on FAN PWM and remove the connector. Repeat this for LED PWM. Pull the black pieces in SAFETY1 and SAFETY 2 (jumpers) straight out. Place these off the side with your spacers and ferrite core. We will plug them into the new board. There is an empty space labeled ANALOG. To the right of that is FAN 5V (the wires are blue and orange). Remove the connector. Unplug TEMP 1 and TEMP 3 the same way you unplugged FAN PWM. 

Now we'll do the wires in the green blocks on the right side. If the top of the green terminal block is silver, it’s a screw connection; if it’s orange, it’s spring loaded. Unscrew the screws to release the hold on the wires (note: the screw will not come out of the block). To engage/disengage the spring, press down on the orange part with a flat screwdriver. Remove wires while the orange piece is depressed. Your board should now be free of wires.

8. We're going to install the new board next. Orient the new board the way we had the old one (post-side up, green blocks on the right, power switch opposite you). This time we will start on the right side at the green blocks. You have two sets of wires that lack a connector at the tip. One set is white, and the other is grey (in some machines the second set will be blue and brown instead). Let's start with the white wires. Since they come out on the left side, they have to cross the board to be plugged in. Do this so that the wires are UNDER the board. You will have to depress the spring by pressing the orange piece to insert the wires.

The white wires go in the green block at the top. Each white wire has its own hole. Make sure the bare wire is completely in the block, but do not insert black insulation. If the insulation is caught in the block, the heater will have a bad connection and will not heat. The grey wires also go under the board. They plug into the bottom block. There is one hole for each wires. Insert them the same way as the white wires, being careful not to catch the insulation in the block. Gently tug on each of the four wires to ensure they are secure in the blocks. Before we move on, we're going to double check that the wires are in the correct blocks. Lift your board so that the on/off switch is at the bottom. You can now see the labels for the green blocks. The grey wires should be in HEATED BED, and the white wires should be in HEATER 1. The middle block, HEATER 2, should be empty. If the wires are incorrect, turn your board back over and try again. If the wires are correct, turn the board back over (post-side up, green blocks on the right, power switch opposite you) and continue to the left side.

We will start at the top on the left side. The first connection is labeled FAN PWM. The wires are green and yellow. Carefully plug this in. The second connection is LED PWM. The wires are red and black and come down from the front panel. Next are SAFETY 1 and SAFETY 2. The black jumpers you took out of the old board go in these. It does not matter which way up they go as long as the metal prongs are properly inserted. X-STOP, Y-STOP, and Z-STOP. Let's start with X (blue wires). Plug these in. The flat part of the white connector will be facing down. Continue with Y (the red wires) and then Z. The Z (black wires) come from the right side of the board. The wires should cross the board on the underside like the heater wires. The ANALOG spot is empty. Plug the blue and orange wires into FAN 5V directly to the right of the ANALOG port. The flat side of the white connector should be to the right. The plug with the white and red wire goes into TEMP 1. The plug with the (usually) black wires goes into TEMP 3. The middle port, TEMP 2 remains empty. We will do the other wires once we have reattached the board.

Let's review the left side and make sure we have all the wires in the correct places before we reattach the board. Starting at the top: green/yellow; red/black; jumper; jumper; blue; red; black; ANALOG empty, FAN 5V blue/orange; white/red; TEMP 2 empty; black.

Remember that if your UM2 came with the extra modification wire (red/brown), it should be left unplugged. Simply tuck it to the side out of the way where the cover will still contain it. It is possible to remove this wire entirely if you desire. However that requires removing it from the entire length of the hot end braid, which can be quite time consuming. It's easier to just leave it installed and unplugged.

9. Now we can put the board back on the printer using the four longest screws (25mm) and the four black spacers. Start with the bottom two screws. Place them through the front panel and put a spacer on each one. Lift the board so the power switch is at the bottom. Carefully place the board so that the power switch, cable terminal, and the power cord terminal set neatly in the cutouts on the back panel. Make sure none of the wires are pinched under the board and that the only wire that goes between the board and the panel is the blue/orange one. Get the bottom two screws started into the posts. Then carefully do the same for the top screws and spacers. Avoid bending the board back. Before tightening all the screws down, set the board so that the bottom edge is flush with the back panel. Now tighten the screws.

Now we'll finish plugging in the remaining wires. The flat cables on the left side are not interchangeable, although they look the same. Plug the wire labeled 1 into EXP1, and the wire labeled 2 into EXP 2. The flat part of the connector goes toward the board. The part of the connector with the protrusion goes toward the panel. 

We have four motor wires remaining. If you labeled them when you took them out, it will be easy to just plug them back in. If you didn't label them, don't worry. We can figure out which is which. The flat part of the connectors will be against the board. We are going to start with the X. There are two motor wires that come from the right side of the printer. Follow the wire that comes down through the bottom panel on the right side and then goes under the motor block next to the board. This is the X wire. Now we will do the Y. There are two motor wires that come from the left side. Gently straighten them so we can compare the length. The shorter of the two is the Y. The remaining motor wire on the right side (that comes directly from the motor block next to the board) is the Z. The remaining wire on the left side is E1 (the longer wire when you compared the lengths). 

10. You should still have a ferrite core off to the side. The ferrite core will go around the motor wires on the left side. Place Y and E1 inside the core and snap it closed. Make sure only Y and E1 are inside and that nothing is pinched. Adjust the ferrite core so that it is next to (left side) the electronics board AND does not put pressure on any of the plugged in wires.


11. It's finally time to put the covers back on. Let's do the one that goes over the board first. Make sure the flat cables (EXP1 and EXP2)  the LED wire (red/black) exit through the opening on the top left of the cover. Do not pinch the wires. There is an opening on the bottom right for the x-motor wire, z-motor wire, and z-stop wire. Do not pinch the wires. There are tabs on the cover that go into each of the three adjacent panels. Secure the cover with the larger of the screws you have left (12mm) and two locknuts which you will need to hold with pliers or a nut driver. You can stand your printer up now.

Lower the bed and then put the corner cover in place. Using the two screws you have left (8mm), secure the cover (one screw in the side panel, one screw in the back panel).

 12. Update your firmware before attempting to print; several models of Ultimaker printers use the same electronics board, but with different firmware, and it is essential to use the right firmware or your printer will not operate correctly.


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