# Pwr communication failed at reg 0: I2C read word failed: \[Errno 121\] Remote I/O error

**URL:** https://forum.onefinitycnc.com/t/pwr-communication-failed-at-reg-0-i2c-read-word-failed-errno-121-remote-i-o-error/18177
**Category:** Troubleshooting (X35/X50)
**Created:** [January 16, 2023, 4:39pm UTC](https://forum.onefinitycnc.com/t/pwr-communication-failed-at-reg-0-i2c-read-word-failed-errno-121-remote-i-o-error/18177 "2023-01-16T16:39:33Z")
**Posts on this page:** 1
**Page:** 2

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### Author: ![debheadworth](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.onefinitycnc.com/debheadworth/32/24591_2.png) [@debheadworth](https://forum.onefinitycnc.com/u/debheadworth)
#### Post date: [June 19, 2023, 10:01pm UTC](https://forum.onefinitycnc.com/t/pwr-communication-failed-at-reg-0-i2c-read-word-failed-errno-121-remote-i-o-error/18177/21 "2023-06-19T22:01:17Z")

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Really nice controller case!!

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