<p>The MOSFET is either dead, or can't handle the high current the bed requires. You can try using an external MOSFET which is quite easy to wire, or alternatively soldering a new MOSFET one which is quite difficult.</p>
<p>Example of an external MOSFET (module):</p>
<p><a href="https://i.sstatic.net/ZxM2a.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/ZxM2a.png" alt="enter image description here" /></a></p>

CC BY-SA 4.0
2022-08-05T11:17:45.217Z
2022-08-06T13:47:49.110Z
2022-08-06T13:47:49.110Z
F.Ahmed
<p>When I boot the Flsun Cube F5 with an MKS Gen L v1.0 controller board, it boots fine; it beeps, and all the LEDs come on. When I heat the hotend it works beautifully, and once up to temperature, the extruder motor feeds just like it should.</p>
<p>However, when I turn on the heater of the build plate, it starts heating and after about 10-12 seconds the board, specifically the MOSFET at the heat bed connection quickly begins to get hot and starts to smoke. I feel if I let it continue, either the board would catch on fire or at least burn out the board.</p>
<p>Does anybody have any suggestions as to how to fix this?  I still haven't tried the X, Y, and Z steppers yet, but that will be coming soon.</p>

CC BY-SA 4.0
2022-07-22T09:58:39.707Z
Dear Brian, if you are referring to [this](https://3dprinting.stackexchange.com/questions/19629/mks-gen-l-v-1-0-problems) previous question, please add an answer or delete the question (preferably answer your question and accept the answer after 48 hours). It might be beneficial to other with similar problems! Thanks.
0scar
<marlin><troubleshooting><heated-bed>
MKS Gen L v1.0 smoking when I heat up the build plate
Brian Eddy
# MKS Gen L v1.0 smoking when I heat up the build plate

(Asked by: username_0 on 2022-07-22)

When I boot the Flsun Cube F5 with an MKS Gen L v1.0 controller board, it boots fine; it beeps, and all the LEDs come on. When I heat the hotend it works beautifully, and once up to temperature, the extruder motor feeds just like it should.

However, when I turn on the heater of the build plate, it starts heating and after about 10-12 seconds the board, specifically the MOSFET at the heat bed connection quickly begins to get hot and starts to smoke. I feel if I let it continue, either the board would catch on fire or at least burn out the board.

Does anybody have any suggestions as to how to fix this? I still haven't tried the X, Y, and Z steppers yet, but that will be coming soon.

**Tags:** marlin, troubleshooting, heated-bed

> **Comments:**
> **username_1**: Dear username_0, if you are referring to [this](https://3dprinting.stackexchange.com/questions/19629/mks-gen-l-v-1-0-problems) previous question, please add an answer or delete the question (preferably answer your question and accept the answer after 48 hours). It might be beneficial to other with similar problems! Thanks.  

---

## 1 answers

### Answer by username_2 on 2022-08-05. Score: 1

The MOSFET is either dead, or can't handle the high current the bed requires. You can try using an external MOSFET which is quite easy to wire, or alternatively soldering a new MOSFET one which is quite difficult.

Example of an external MOSFET (module):

[![enter image description here](https://i.sstatic.net/ZxM2a.png)](https://i.sstatic.net/ZxM2a.png)


---

