MKS Base Reverse Polarity Repair


Introduction: MKS Base Reverse Polarity Repair

About: I am 21 years old, hard working and excited about doing stuff around technology. I fell in love with technology at the age of 7, where i started taking my dad's tools, and opening every device in the house ...

I was up all night, and decided at 5 am to fix my Printers input, because it had broken a few days ago. So I replaced the connector, but confused the polarity, yes I know, clever me, and I broke the board.

It wouldn't work from the power input, but it still would work from a USB, the motors wouldn't work of course.

My board was MKS Base V1.2

Sorry for the quality of the pictures, my phone has 5mp only with no manual focus and terrible autofocus.

Step 1: Step 1. Check the Fuse

Check with the continuity function of your multimeter across the F3 Fuse (near the power input)

If you have continuity continue to the next step.

otherwise replace the fuse.

Step 2: Step 2: Replace the Regulator

Disolder the regulator, clean the pads, and make sure you don't have any short circuit.

Solder a new regulator (L5970D) make sure you don't have any short circuits between the pins of the regulator.

PS: Be careful the resistors and capacitors next to the regulator so that you don't disolder them. I had to fiddle with R5, because I wasn't careful.



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11 Discussions

15 Ampere. Now you should measure the dimension of the fuse for buying a new one. i see this on ebay also.

Hi Lipigl, I can't find F15 could you send me a photo marking it?


8 months ago

Hi, I have a MKS GEN v.10 biqutreetech . after wrong polarity connection is dead... one diode burn.. i have change two diode but nothing.. one fuse ok but another no.. what is the valor of these fuse? 15 is 15A ??

1 reply

Question 3 months ago

Thanks for helping!

It's not F15, it's a fuse with the number 15 on it. I'm using the MKS Gen L and I messed it up by reversing the psu polarity. I was hoping the fuses would be similar in your board.

1 more answer

I am sorry but I don't know which fuse it uses, and they still haven't published schematics and BOM "Open Source" my A**.

But according to reprap Wiki it is a remix of Arduino mega2560 and RAMPS1.4.

And according to the photo you send the fuze 15 is actually fuze F2 on the board,

on ramps F2 fuze is a ressetable PTC fuze that is guaranteed to not trip at 11Amps and guaranteed to trip at 22Amps and maximum voltage of 16V. But since the MKS claims to work on 24V that wouldn't work. I did a quick search on digikey (I am not sure if the fuze is an 0603) but there where options at 24V for 15A (which I guess the number 15 means) I couldn't find one for 32V as a buffer. Sorry I can't be of more help

MKS Base V1.1 - Does it look like I should replace the Fuse?
My multi-meter has no continuity setting; any idea what resistance should I be looking for over f3?

2 replies

If it is a fuse, there should almost no resistance.

Sorry for taking so long to respond, I just logged in after almost a year

A fuse, it should have almost not existent, resistant, like a piece of wire.

Good info, thank you for sharing. And welcome to instructables!