Summary

A new e‑Series joint hardware revision requires a minimum PolyScope version. If the joint is installed on older software, the joint may not start during boot, and the robot may fail to start.

Symptoms

After a joint replacement (or installing a spare joint), you may observe one or more of the following:

• The robot won’t boot / fails to start.
• Error code C343A0 (typical symptom) shown during startup.

Cause

The new e‑Series joint hardware revision is not compatible with older PolyScope versions, so the joint can be prevented from starting at boot.

Minimum software requirements (PolyScope 5)

• PolyScope 5 (mainline): 5.20 or newer is required. Versions 5.19 and older may fail to start the joint at boot (typical symptom: C343A0, robot fails to start).
• PolyScope 5.12 LTS: Compatibility is provided via the 5.12 LTS patch line; 5.12.7 is available on the support site,

(For general PolyScope 5 documentation and version context, see the PolyScope 5.20 documentation landing page.)

Recommended action

If you see C343A0 (or the robot won’t boot) after replacing a joint:

1. Check the robot’s current PolyScope version.
2. If the version is below the minimum requirement, update PolyScope first and retry startup.
3. Do not assume the spare joint is faulty before confirming the software is updated to the required minimum.

If you are “version‑locked”

If you cannot update software due to internal validation requirements or other constraints, contact Universal Robots support / your distributor for guidance on next steps.

Notes

• This service note is specifically about minimum software compatibility for the new e‑Series joint hardware revision and the startup failure symptom (C343A0) when running on older software.