WINCH_MOTOR_TYPE_UNKNOWN
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Applicable alarms (1)
WINCH_MOTOR_TYPE_UNKNOWN
Likely outcomes — click to expand
Based on 390,633 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 2,541 ZERP issues filed on these missions)
Top work orders
- EV3: Inspect Aircraft after Droid Left Behind (DLB) · MAINTENANCE_ACTION 83
- EV2: Replace Aft Motor Assembly on Aircraft · MAINTENANCE_ACTION 37
- EV2: Troubleshoot Electrical Contacts on Aircraft and Droid · INSPECTION 35
- Troubleshoot Hover Motor Resistance on Aircraft · INSPECTION 31
- Reset Droid Lid · TROUBLESHOOTING 21
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| TAIL STBD DEPOP, ZIP, P2 | 21840 | 444 |
| CCW HOVER MOTOR ASSY, EV3 ZIP, P2 | 19607 | 430 |
| PRE-PREG TAIL ASSY, AL, PORT(LH), ZIP, P2 | 31280 | 423 |
| SERVO TOP LVL ASSY, UNIVERSAL | 20398 | 422 |
| ASSY, SPOOL AND LINE, DOCKING FIN | 48477 | 306 |
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm occurs when winch GNC does not recognize the version of the installed winch motor.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
is-the-winch-motor-disabled-alarm-prese{"<small><b>Step 1</b></small><br/>Question: Is the WINCH_MOTOR_DISABLED/topics..."}
refer-to-the-guide-for-winch-motor-dis("<small><b>Step 2</b></small><br/>Reference: Refer to the guide for WINCH_MOTOR_D...")
switch-to-winch-motor-disabled-check-co["<small><b>Step 3</b></small><br/>Action: Switch to the WINCH MOTOR DISABLED -..."]
check-for-a-gap-on-the-top-plot-but-not["<small><b>Step 4</b></small><br/>Action: Check for a data gap on the top plot,..."]
are-these-conditions-met{"<small><b>Step 5</b></small><br/>Question: Are these conditions met? **NOTE**: T..."}
escalate-to-p2-embedded-platform-on-cal{{"<small><b>Step 6</b></small><br/>Escalation: Escalate to P2 Embedded Platform On C..."}}
escalate-to-p2-droid-controls-on-call{{"<small><b>Step 7</b></small><br/>Escalation: Escalate to P2 Droid Controls On Call."}}
is-the-winch-motor-disabled-alarm-prese -->|Yes| refer-to-the-guide-for-winch-motor-dis
is-the-winch-motor-disabled-alarm-prese -->|No| switch-to-winch-motor-disabled-check-co
switch-to-winch-motor-disabled-check-co --> check-for-a-gap-on-the-top-plot-but-not
check-for-a-gap-on-the-top-plot-but-not --> are-these-conditions-met
are-these-conditions-met -->|Yes| escalate-to-p2-embedded-platform-on-cal
are-these-conditions-met -->|No| escalate-to-p2-droid-controls-on-call
style is-the-winch-motor-disabled-alarm-prese fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style refer-to-the-guide-for-winch-motor-dis fill:#f3e8ff,stroke:#a855f7,color:#581c87
style switch-to-winch-motor-disabled-check-co fill:#dcfce7,stroke:#22c55e,color:#14532d
style check-for-a-gap-on-the-top-plot-but-not fill:#dcfce7,stroke:#22c55e,color:#14532d
style are-these-conditions-met fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style escalate-to-p2-embedded-platform-on-cal fill:#fef3c7,stroke:#f59e0b,color:#78350f
style escalate-to-p2-droid-controls-on-call fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Is the WINCH_MOTOR_DISABLED alarm present?
2 reference
Refer to the guide for WINCH_MOTOR_DISABLED
3 action
Switch to the
WINCH MOTOR DISABLED - Check compute b->a connection Baraza template with 30s of padding. 4 action
Check for a data gap on the top plot, with no matching gap on the middle plot, that lines up with the WINCH_MOTOR_TYPE_UNKNOWN signal on the bottom plot being true.
5 question
Are these conditions met?
NOTE: The plot below is an example of the conditions being met. This example is shared with the WINCH_MOTOR_DISABLED guide because both checks use the same Baraza template.
NOTE: The plot below is an example of the conditions being met. This example is shared with the WINCH_MOTOR_DISABLED guide because both checks use the same Baraza template.
6 escalation
Escalate to P2 Embedded Platform On Call.
7 escalation
Escalate to P2 Droid Controls On Call.
Resolution note
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