# C4A16 Communication Issue with Joint 4

**URL:** <https://forum.universal-robots.com/t/c4a16-communication-issue-with-joint-4/5281>\
**Category:** Technical Questions\
**Tags:** error-code, joints\
**Created:** [October 8, 2019, 12:52am UTC](https://forum.universal-robots.com/t/c4a16-communication-issue-with-joint-4/5281 "2019-10-08T00:52:07Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![anon91700237](https://avatars.discourse-cdn.com/v4/letter/a/8c91f0/32.png) [@anon91700237](https://forum.universal-robots.com/u/anon91700237)\
**Post date:** [October 8, 2019, 12:52am UTC](https://forum.universal-robots.com/t/c4a16-communication-issue-with-joint-4/5281/1 "2019-10-08T00:52:07Z")

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Hello,

I own a UR3 (serial # 2016331332). I am running PolyScope version 3.9.0.64176

Out of the blue, I started receiving the following error:

![image](https://us1.discourse-cdn.com/flex020/uploads/universal_robots/original/2X/c/cc315792991ce9ae6f9986aa8da140228f830523.png).

I tried performing a complete reboot sequence but did not that change anything. What could I do to resolve this?

Thanks - Manish

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**Author:** ![inu](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/inu/32/732_2.png) [@inu](https://forum.universal-robots.com/u/inu)\
**Post date:** [October 8, 2019, 3:40pm UTC](https://forum.universal-robots.com/t/c4a16-communication-issue-with-joint-4/5281/2 "2019-10-08T15:40:39Z")

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Hello @anon91700237,

I would contact your local support team, or distributor for further assistance. They can help troubleshoot further, in the case of any issues with the communication wiring on the joint, they can also help you with the next steps if a joint replacement is needed.

When you contact them if you could provide a log file, serial number, and short description on when you encountered the error they can work promptly to resolve the issue.

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<div class="post-metadata">

**Author:** ![anon91700237](https://avatars.discourse-cdn.com/v4/letter/a/8c91f0/32.png) [@anon91700237](https://forum.universal-robots.com/u/anon91700237)\
**Post date:** [October 10, 2019, 1:42am UTC](https://forum.universal-robots.com/t/c4a16-communication-issue-with-joint-4/5281/3 "2019-10-10T01:42:33Z")

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Thanks Inu - I’m in touch with them and trying to get it resolved. I’ve sent over logs and photos to figure out more.

While I have you and your staffmates here - does anything seem off from any of the below?

Log dump: [https://manish-dev-test.s3-us-west-1.amazonaws.com/2016331332.zip](https://manish-dev-test.s3-us-west-1.amazonaws.com/2016331332.zip)  
Photo of J4 with cap removed: [https://photos.app.goo.gl/oBx51hWTA6iGVxvs5](https://photos.app.goo.gl/oBx51hWTA6iGVxvs5)  
Video of J4 with cap removed: [https://photos.app.goo.gl/E2P4UEZSKEkcdojQ9](https://photos.app.goo.gl/E2P4UEZSKEkcdojQ9)

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<div class="post-metadata">

**Author:** ![anon15994355](https://avatars.discourse-cdn.com/v4/letter/a/eb8c5e/32.png) [@anon15994355](https://forum.universal-robots.com/u/anon15994355)\
**Post date:** [April 29, 2023, 11:59pm UTC](https://forum.universal-robots.com/t/c4a16-communication-issue-with-joint-4/5281/4 "2023-04-29T23:59:51Z")

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I have the same problem. what was the solution?