GNSS_RECEIVER_STARTUP_COMMAND_TIMEOUT
Applicable alarms (1)
Likely outcomes — click to expand
Based on 9 missions where this alarm fired in the last 90 days as of 2026-10-13
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm means the EV2 GNSS receiver did not respond to startup configuration commands from gnss_task. The task retries startup configuration before publishing this alarm, so a persistent alarm usually points to a hardware issue between the flight compute and the GNSS receiver.
This alarm blocks preflight until the issue is resolved.
This alarm may appear with other navigation or GNSS-related blockers because the GNSS receiver never finished startup. Treat GNSS_RECEIVER_STARTUP_COMMAND_TIMEOUT as the primary failure if it is present.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
determine-the-impacted-compute["<small><b>Step 1</b></small><br/>Action: Check if the alarm is set on compute ..."]
replace-the-affected-flight-compute-assembly["<small><b>Step 2</b></small><br/>Action: Replace the affected Flight Compute A..."]
run-maintenance-health-check["<small><b>Step 3</b></small><br/>Action: Perform a Zip maintenance health che..."]
did-replacement-clear-the-alarm{"<small><b>Step 4</b></small><br/>Question: Did the alarm clear after the Flight ..."}
return-the-aircraft-to-service-after-replacement["<small><b>Step 5</b></small><br/>Action: The Aircraft may return to service."]
escalate-with-alarm-context{{"<small><b>Step 6</b></small><br/>Escalation: Escalate to P2 Avionics Hardware On C..."}}
determine-the-impacted-compute --> replace-the-affected-flight-compute-assembly
replace-the-affected-flight-compute-assembly --> run-maintenance-health-check
run-maintenance-health-check --> did-replacement-clear-the-alarm
did-replacement-clear-the-alarm -->|Yes| return-the-aircraft-to-service-after-replacement
did-replacement-clear-the-alarm -->|No| escalate-with-alarm-context
style determine-the-impacted-compute fill:#dcfce7,stroke:#22c55e,color:#14532d
style replace-the-affected-flight-compute-assembly fill:#dcfce7,stroke:#22c55e,color:#14532d
style run-maintenance-health-check fill:#dcfce7,stroke:#22c55e,color:#14532d
style did-replacement-clear-the-alarm fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-the-aircraft-to-service-after-replacement fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-with-alarm-context fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1. UMM: Remove Flight Compute Assembly (FCA)
2. UMM: Install Flight Compute Assembly (FCA)
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