TAIL_NODE_COMMS_MISSING
Background
Section titled “Background”A mission may fail this validator check if Tail-Node (Tail-Bridge) is not detected on the network or if it disappears from the network mid-flight. There may be multiple underlying causes of this issue:
- The respective load switch faulted (mixed motor overcurrent)
- The node’s busbars got disconnected (open circuit)
- Physical damage to the board/flex mating connector causing no link on either side.
Follow the guide to rule out possible causes, if none of the cases match, escalate to P2 Firmware Platform On Call.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
did-tail-node-comms-missing-fail{"<small><b>Step 1</b></small><br/>Question: Did TAIL_NODE_COMMS_MISSING check f..."}
mixed-motor-slip-check{"<small><b>Step 2</b></small><br/>Question: Does the mixed motor show signs of sh..."}
re-check-failed-validator-check["<small><b>Step 3</b></small><br/>Action: You might have matched the wrong fail..."]
escalate-to-fw-platform{{"<small><b>Step 4</b></small><br/>Escalation: Escalate to P2 Firmware Platform On C..."}}
follow-mixed-motor-slip-guide["<small><b>Step 5</b></small><br/>Action: Follow the resolution of the Mixed M..."]
did-tail-node-comms-missing-fail -->|Yes| mixed-motor-slip-check
did-tail-node-comms-missing-fail -->|No| re-check-failed-validator-check
mixed-motor-slip-check -->|Yes| follow-mixed-motor-slip-guide
mixed-motor-slip-check -->|No| escalate-to-fw-platform
style did-tail-node-comms-missing-fail fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style mixed-motor-slip-check fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style re-check-failed-validator-check fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-to-fw-platform fill:#fef3c7,stroke:#f59e0b,color:#78350f
style follow-mixed-motor-slip-guide fill:#dcfce7,stroke:#22c55e,color:#14532d Hover or focus a block to preview it. Select the block to keep the preview open.
TAIL_NODE_COMMS_MISSING check fail in mx_ethernet_node validator?Follow this page to find out: Check Mixed Motor Shaft Slip
Make sure you match the correct failing validator check from the table.
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