# Spindle "logic" DOA

**URL:** <https://community.inventables.com/t/spindle-logic-doa/10659>\
**Category:** Troubleshooting\
**Created:** [July 14, 2015, 3:52pm UTC](https://community.inventables.com/t/spindle-logic-doa/10659 "2015-07-14T15:52:24Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![HansGerwitz](https://yyz1.discourse-cdn.com/flex009/user_avatar/community.inventables.com/hansgerwitz/32/67314_2.png) [@HansGerwitz](https://community.inventables.com/u/HansGerwitz)\
**Post date:** [July 14, 2015, 3:52pm UTC](https://community.inventables.com/t/spindle-logic-doa/10659/1 "2015-07-14T15:52:24Z")

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I’ve finally gotten around to upgrading my Shapeoko 2, and everything seems to be working. But the “logic” mode never provides power to the spindle.

In a brief attempt to troubleshoot, I bypassed the controller altogether and jumped the logic contacts with a bit of wire, and even that doesn’t work. So I figured there’s a dead relay or whatnot.

Taking the power supply back apart, I see the relevant MOSFET assembly has a contact that isn’t soldered but that’s just the heat shield and I assume irrelevant?

I’m just a software guy, can someone who’s a little more EE help me diagnose this? Asking Inventables to just send another part is a last resort, since they take a long time to get here to Europe.

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**Author:** ![BrianSaban](https://yyz1.discourse-cdn.com/flex009/user_avatar/community.inventables.com/briansaban/32/84709_2.png) [@BrianSaban](https://community.inventables.com/u/BrianSaban)\
**Post date:** [July 14, 2015, 4:04pm UTC](https://community.inventables.com/t/spindle-logic-doa/10659/2 "2015-07-14T16:04:44Z")

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Double check your connections on your arduino pins, what version of grbl are you using? remember the pins change on 9

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**Author:** ![sketch42](https://yyz1.discourse-cdn.com/flex009/user_avatar/community.inventables.com/sketch42/32/76722_2.png) [@sketch42](https://community.inventables.com/u/sketch42)\
**Post date:** [July 14, 2015, 10:29pm UTC](https://community.inventables.com/t/spindle-logic-doa/10659/3 "2015-07-14T22:29:57Z")

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There are some that did have trouble with a MOSFET and the spindle control. Inventables sent out a new one if I recall correctly.

My suggestion is to contact them via email and they will get you sorted… [help@inventables.com](mailto:help@inventables.com)

I think this thread is where I saw it, but there may be others:

> [@Spindle will not turn off (Resolved)](https://community.inventables.com/t/spindle-will-not-turn-off-resolved/9186):
>
> I have been reading through the other troubleshooting tips and have t seen a solution for this. I have my x-carve fully assembled and yesterday everything was perfect except for the limit switches. In the process of checking for continuity of the limit switch wires at the gshield connection, the spindle suddenly came on. Now it won’t go off. I have rebooted the PC, Power Supply, cycled the switch between On, Off, Logic, and even pressed the reset button on the gshield. The only way to turn off …

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**Author:** ![HansGerwitz](https://yyz1.discourse-cdn.com/flex009/user_avatar/community.inventables.com/hansgerwitz/32/67314_2.png) [@HansGerwitz](https://community.inventables.com/u/HansGerwitz)\
**Post date:** [July 15, 2015, 9:26am UTC](https://community.inventables.com/t/spindle-logic-doa/10659/4 "2015-07-15T09:26:01Z")

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I’m on a version of Grbl 0.9 … not sure it’s “i” but my next step is to re-flash anyway.

I was hoping that shorting the logic pins together would eliminate the Arduino entirely. Is that not true?