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MCM4 Short Circuit - Repair Help!

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Hi everyone, 


Opened up my MCM4 yesterday and found the wires leading to the LEDs was kind of torn open. While working on it the cable came in contact with the circuit board. It made a bright spark and now the unicycle won't turn on. I assume it's a blown circuit but there's no evident damage to anything and I'm fairly inexperienced with electrical work. Does anyone have any tips or ideas on what exactly is wrong and how/if I can fix it? 

Any help would be super appreciated. 




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I'm not experienced with the MCM4 but I have fixed my EUC when needed using the following methods.


Do you have a multimeter?

Use it to check that

- There is power coming from the battery to the circuit board. (if not follow the wiring back to the problem spot and resolder the connection or replace the faulty wire/part or buy a new circuit board)

- Make sure it outputting the correct power from the battery. (If not replace battery or if you are feeling brave....)

- Check that you are getting the correct voltage from each cell. (Replace any dodgy cells)

(Much MUCH easier to replace the battery)

- Unfortunately the BMS will usually have a separate fuse for each cell. If one of them has gone your best bet would be to replace the BMS or buy a new battery. (Again, buying a new battery is easiest as it comes with a new BMS too)

The motors in these things are pretty robust so its not often the problem. If it is you may be in for a new wheel.

From what you have said I would guess that you have fried the circuit board. Easiest way to fix this would be to contact the supplier or dealer and order a new circuit board to replace the faulty one)

Be VERY careful when working with these batteries. They have a hell of a kick and electrical burns are savage.

If your not confident, I'd talk to your local dealer. They may be able to repair it for you for a cost... or not, if it is under warranty.



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