ADSB_MODULE_NOT_READY
Applicable alarms (1)
Likely outcomes — click to expand
Based on 869,699 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 5,773 ZERP issues filed on these missions)
Top work orders
- EV3: Inspect Aircraft after Droid Left Behind (DLB) · MAINTENANCE_ACTION 215
- Troubleshoot Hover Motor Resistance on Aircraft · INSPECTION 77
- EV2: Troubleshoot Electrical Contacts on Aircraft and Droid · INSPECTION 71
- Reset Droid Lid · TROUBLESHOOTING 57
- EV2: ZCO-2026-08-03 Lower Foam Wear Pad Retrofit (FRCO-286 / SB-2026-023) · UPGRADE_RETROFIT 35
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| SERVO, ASSY, UNIVERSAL, P2 | 20398 | 983 |
| CW/CCW HOVER MOTOR ASSY, ZIP, P2 | 19607 | 822 |
| ASSY, SPOOL AND LINE, DOCKING FIN, AIRCRAFT, P2 | 48477 | 782 |
| PRE-PREG TAIL ASSY STBD(RH), ZIP, P2 | 21840 | 684 |
| TAIL PORT DEPOP, ZIP, P2 | 31280 | 651 |
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm is set if we fail to connect to the ADSB module on one of the Aircraft compute boards.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
power-cycle-aircraft-link("<small><b>Step 1</b></small><br/>Reference: Power Cycle Aircraft/procedures/po...")
perform-preflight["<small><b>Step 2</b></small><br/>Action: Send a Run Health Checks mission in F..."]
has-the-alarm-cleared{"<small><b>Step 3</b></small><br/>Question: Has the alarm cleared?"}
return-aircraft-service("<small><b>Step 4</b></small><br/>Reference: Return the Aircraft to service")
replace-compute-board["<small><b>Step 5</b></small><br/>Action: Replace the compute board - UMM: Remo..."]
did-this-remedy-issue{"<small><b>Step 6</b></small><br/>Question: Did this remedy the issue?"}
return-aircraft-service-2("<small><b>Step 7</b></small><br/>Reference: Return the Aircraft to service")
escalate-p2-avionics-on-call{{"<small><b>Step 8</b></small><br/>Escalation: Escalate to P2 Avionics Hardware On C..."}}
power-cycle-aircraft-link --> perform-preflight
perform-preflight --> has-the-alarm-cleared
has-the-alarm-cleared -->|Yes| return-aircraft-service
has-the-alarm-cleared -->|No| replace-compute-board
replace-compute-board --> did-this-remedy-issue
did-this-remedy-issue -->|Yes| return-aircraft-service-2
did-this-remedy-issue -->|No| escalate-p2-avionics-on-call
style power-cycle-aircraft-link fill:#f3e8ff,stroke:#a855f7,color:#581c87
style perform-preflight fill:#dcfce7,stroke:#22c55e,color:#14532d
style has-the-alarm-cleared fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-aircraft-service fill:#f3e8ff,stroke:#a855f7,color:#581c87
style replace-compute-board fill:#dcfce7,stroke:#22c55e,color:#14532d
style did-this-remedy-issue fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-aircraft-service-2 fill:#f3e8ff,stroke:#a855f7,color:#581c87
style escalate-p2-avionics-on-call fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
- UMM: Remove Flight Compute Assembly
- UMM: Install Flight Compute Assembly
Resolution note
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