> ## Documentation Index > Fetch the complete documentation index at: https://docs.wuji.tech/llms.txt > Use this file to discover all available pages before exploring further. # Troubleshooting This page gives diagnostic steps by symptom. For device stop behavior, emergency stop and fault-clearing, and maintenance and storage requirements, see [Maintenance](/en/docs/wuji-hand/latest/maintenance). For SDK installation, connection, and subscription problems, see [Wuji SDK troubleshooting](/en/docs/wuji-sdk/troubleshooting/). ## Device Discovery Failure 1. Check whether the back-of-hand status light is on. If there's no light at all, check the power supply and the XT30 power connector first 2. Check that both ends of the network cable are seated 3. Confirm your computer's network adapter uses a static IP on the same subnet (default subnet `192.168.1.x`, see [Quick Start](/en/docs/wuji-hand/latest/quick-start#step-4-configure-the-host-network-adapter)) 4. `ping` the device IP: `192.168.1.110` for the left hand, `192.168.1.111` for the right hand If your computer has several network adapters, upgrade Wuji SDK to the latest version first, then disable the others and try again. If the device still isn't found, export the logs and contact support (see [Export Logs and Contact Support](#export-logs-and-contact-support)). ## Connection Fails or IPs Conflict Two devices of the same handedness on one subnet share a default IP, which conflicts: 1. Connect only one device first 2. Change the IP of one of them, following [SDK Reference](/en/docs/wuji-hand/latest/sdk-reference/device-operations#ip-set/get) 3. Put both devices on the network again, and connect by serial number (`sn`) With several devices of the same handedness on the network, `connect(handedness=...)` raises `AmbiguousHandedness`. Specify the device with `sn` instead. If there's no IP conflict and the connection still fails, check whether another program holds local port 50001, and upgrade Wuji SDK to the latest version. ## The Status Light Shows a Warning or Fault For what each level means, see [Product Introduction](/en/docs/wuji-hand/latest/product-introduction#back-of-hand-status-light). Handle each pattern as follows: * **Yellow slow flash (warning)**: subscribe to `joint_diagnostics`, check the active error codes, and decode them with `WujiHand2.describe_error(code)`. Warnings are mostly early alerts—remove the cause (cooling, wiring, load), and keep working. * **Red slow flash (fault)**: work through [Clear Faults and Reset Safely](/en/docs/wuji-hand/latest/maintenance#clear-faults-and-reset-safely) above—decode the error code, remove the cause, clear the fault, then enable again. If it keeps coming back, contact support. * **Red solid (critical)**: power-cycle the device. If it recurs, stop using the device, contact support, and follow their repair instructions. ## Communication Drops After Enabling and the Device Stops 1. Check both ends of the network cable and the network gear, and confirm the link to the host is back 2. Subscribe to `joint_diagnostics`, read the active error codes, and decode them with `WujiHand2.describe_error(code)`, then remove the reported cause. 3. Call `enable()` again, and confirm the status light turns white solid The device doesn't resume motion on its own once communication returns. For the full stop-and-recovery behavior, see [Communication Loss Behavior](/en/docs/wuji-hand/latest/maintenance#communication-loss-behavior) above. If the link keeps dropping, follow [Export Logs and Contact Support](#export-logs-and-contact-support) below. ## A Joint Is Offline (Fewer Than 20 Online) 1. Confirm the online joint count with `hand.online_joints_count().get()` 2. Subscribe to the `joint_diagnostics` stream and locate the offline joint by its `nid` 3. Power down, then check the flex cable and connector of that finger for looseness 4. Reseat the connector and power up for a self-check A single failed finger doesn't stop the other joints from working, and the device keeps warning. If reseating doesn't help, the cause is usually hardware, and the fix is a whole-finger replacement. For what you can service yourself, see [What You Can Service](/en/docs/wuji-hand/latest/maintenance#what-you-can-service) below. Spare parts and replacement steps aren't available yet, so contact support to get them. ## Enabling Fails 1. Subscribe to the `joint_diagnostics` stream, check the active error codes, and decode them with `WujiHand2.describe_error(code)` 2. Act on the `clear_policy` returned: * `AutoClear`: remove the cause and wait for the fault to clear itself * `ManualClear`: remove the cause, call `clear_fault()`, then enable again * `NonClearable`: power-cycle the device. If the fault recurs, stop using the device and contact support 3. Call `enable()` again, and confirm the status light turns white solid ## Over-Temperature or Over-Current Faults * **Over-temperature**: wait for the device to cool down and recover automatically. Improve cooling, and lower the load or duty cycle * **Over-current**: check the load and wiring, clear the fault, and retry. If it keeps coming back, check the motor and load. If it still recurs, contact support ## Encoder Warnings 1. Subscribe to `joint_diagnostics` to confirm which joint raised the warning and its error code. 2. Power down, then check the wiring and signal quality around that joint, and confirm the joint area is away from magnetic objects 3. Clear the fault and enable again to verify 4. A warning that keeps coming back is a hardware problem. Contact support ## Firmware Upgrade Fails 1. Follow the error message from the upgrade tool (firmware v2.1.0 and later report detailed errors, while earlier versions give only a summary) 2. Losing power during an upgrade can corrupt the firmware data. Clear the fault and upgrade again 3. If the upgrade keeps failing, contact support For the upgrade flow, see [Wuji CLI firmware upgrade](/en/docs/wuji-cli/firmware-upgrade/). ## Export Logs and Contact Support ```python theme={null} result = hand.export_flash_logs() print(result["path"]) # absolute path to the exported JSONL file print(result["frames"]) # number of exported log records ``` Logs export to `~/.wuji/logs` by default. For usage details, see [SDK Reference](/en/docs/wuji-hand/latest/sdk-reference/diagnostics#flash-log-export-diagnostics). The device keeps at least one week of full logs on board, so anything older needs to be reproduced before you export. When you contact [support@wuji.tech](mailto:support@wuji.tech), include: * The log bundle * The error code and status light pattern * The firmware and SDK versions * Steps to reproduce This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.