ZIP_EXECUTIVE_V4_SERVO_CALIBRATION_FAILED: UNCALIBRATED
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Applicable alarms (5)
ZIP_EXECUTIVE_V4_SERVO_TAIL_PORT_FWD_CALIBRATION_FAILEDZIP_EXECUTIVE_V4_SERVO_TAIL_STBD_FWD_CALIBRATION_FAILEDZIP_EXECUTIVE_V4_SERVO_WING_PORT_FWD_CALIBRATION_FAILEDZIP_EXECUTIVE_V4_SERVO_WING_STBD_FWD_CALIBRATION_FAILEDZIP_EXECUTIVE_V4_TEST_UNCALIBRATED
Likely outcomes — click to expand
Based on 0 missions where this alarm fired in the last
90 days
(for ZIP_EXECUTIVE_V4_SERVO_TAIL_PORT_FWD_CALIBRATION_FAILED) as of 2026-10-13
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”These failures mean that the affected control-surface servo is missing the zero position normally written during end-of-line calibration. They are distinct from RANGE_INCORRECT: run the control-surface EOL test before investigating a range or mechanical problem.
The affected V4 failure can appear as ZIP_EXECUTIVE_V4_SERVO_*_CALIBRATION_FAILED with CAUSED_BY: ZIP_EXECUTIVE_V4_TEST_UNCALIBRATED.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
confirm-uncalibrated-servo-failure{"<small><b>Step 1</b></small><br/>Question: Does the failure include ZIP_EXECUTI..."}
run-control-surface-eol["<small><b>Step 2</b></small><br/>Action: Run the control-surface EOL test for ..."]
evaluate-control-surface-eol{"<small><b>Step 3</b></small><br/>Question: Did the control-surface EOL test pass?"}
classify-control-surface-eol-failure{"<small><b>Step 4</b></small><br/>Question: Why did the control-surface EOL test ..."}
inspect-control-surface-connections["<small><b>Step 5</b></small><br/>Action: Check the affected servo, M5 connecto..."]
rerun-control-surface-eol["<small><b>Step 6</b></small><br/>Action: Rerun the control-surface EOL test as..."]
evaluate-rerun-control-surface-eol{"<small><b>Step 7</b></small><br/>Question: Did the rerun control-surface EOL tes..."}
classify-rerun-control-surface-eol-failure{"<small><b>Step 8</b></small><br/>Question: Why did the rerun control-surface EOL..."}
identify-failed-control-surface{"<small><b>Step 9</b></small><br/>Question: Is this a wing or a tail?"}
follow-removed-wing-flow["<small><b>Step 10</b></small><br/>Action: Follow the Removed Wing Flowchart/..."]
follow-removed-tail-flow["<small><b>Step 11</b></small><br/>Action: Follow the Removed Tail Flowchart/..."]
reinstall-control-surface["<small><b>Step 12</b></small><br/>Action: Re-install the affected control surfa..."]
nominal-preflight-result{"<small><b>Step 13</b></small><br/>Question: Did the nominal preflight pass withou..."}
return-aircraft-to-service["<small><b>Step 14</b></small><br/>Action: The calibration failure is clear. Ret..."]
escalate-uncalibrated-servo{{"<small><b>Step 15</b></small><br/>Escalation: If the nominal preflight still report..."}}
escalate-unconfirmed-uncalibrated-servo{{"<small><b>Step 16</b></small><br/>Escalation: If the failure does not include ZIP_..."}}
escalate-eol-communication-failure{{"<small><b>Step 17</b></small><br/>Escalation: If communication with the control-sur..."}}
confirm-uncalibrated-servo-failure -->|Yes| run-control-surface-eol
confirm-uncalibrated-servo-failure -->|No| escalate-unconfirmed-uncalibrated-servo
run-control-surface-eol --> evaluate-control-surface-eol
evaluate-control-surface-eol -->|Passed| reinstall-control-surface
evaluate-control-surface-eol -->|Failed| classify-control-surface-eol-failure
classify-control-surface-eol-failure -->|Communication| inspect-control-surface-connections
classify-control-surface-eol-failure -->|Range| identify-failed-control-surface
classify-control-surface-eol-failure -->|Free-play| identify-failed-control-surface
inspect-control-surface-connections --> rerun-control-surface-eol
rerun-control-surface-eol --> evaluate-rerun-control-surface-eol
evaluate-rerun-control-surface-eol -->|Passed| reinstall-control-surface
evaluate-rerun-control-surface-eol -->|Failed| classify-rerun-control-surface-eol-failure
classify-rerun-control-surface-eol-failure -->|Communication| escalate-eol-communication-failure
classify-rerun-control-surface-eol-failure -->|Range| identify-failed-control-surface
classify-rerun-control-surface-eol-failure -->|Free-play| identify-failed-control-surface
identify-failed-control-surface -->|Wing| follow-removed-wing-flow
identify-failed-control-surface -->|Tail| follow-removed-tail-flow
reinstall-control-surface --> nominal-preflight-result
nominal-preflight-result -->|Yes| return-aircraft-to-service
nominal-preflight-result -->|No — still UNCALIBRATED| escalate-uncalibrated-servo
style confirm-uncalibrated-servo-failure fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style run-control-surface-eol fill:#dcfce7,stroke:#22c55e,color:#14532d
style evaluate-control-surface-eol fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style classify-control-surface-eol-failure fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style inspect-control-surface-connections fill:#dcfce7,stroke:#22c55e,color:#14532d
style rerun-control-surface-eol fill:#dcfce7,stroke:#22c55e,color:#14532d
style evaluate-rerun-control-surface-eol fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style classify-rerun-control-surface-eol-failure fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style identify-failed-control-surface fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style follow-removed-wing-flow fill:#dcfce7,stroke:#22c55e,color:#14532d
style follow-removed-tail-flow fill:#dcfce7,stroke:#22c55e,color:#14532d
style reinstall-control-surface fill:#dcfce7,stroke:#22c55e,color:#14532d
style nominal-preflight-result fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style return-aircraft-to-service fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-uncalibrated-servo fill:#fef3c7,stroke:#f59e0b,color:#78350f
style escalate-unconfirmed-uncalibrated-servo fill:#fef3c7,stroke:#f59e0b,color:#78350f
style escalate-eol-communication-failure fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Does the failure include
ZIP_EXECUTIVE_V4_TEST_UNCALIBRATED and an affected wing or tail servo calibration alarm? For example: ZIP_EXECUTIVE_V4_SERVO_WING_PORT_FWD_CALIBRATION_FAILED with Reason: Some(TestFailureReason::UNCALIBRATED (repr: 8)). 2 action
Run the control-surface EOL test for the affected wing or tail as described in steps 7–10 of the UMM wing servo motor installation guide. Recent tooling is acceptable, and the EOL application can run from the smart cart.
3 question
Did the control-surface EOL test pass?
4 question
Why did the control-surface EOL test fail?
5 action
Check the affected servo, M5 connector, harness, and connection to the controlling node. Correct any connection issue before rerunning the EOL test.
6 action
Rerun the control-surface EOL test as described in steps 7–10 of the UMM wing servo motor installation guide.
7 question
Did the rerun control-surface EOL test pass?
8 question
Why did the rerun control-surface EOL test fail?
9 question
Is this a wing or a tail?
10 action
Follow the Removed Wing Flowchart. Use the EOL failure result to select the corresponding range or free-play path.
11 action
Follow the Removed Tail Flowchart. Use the EOL failure result to select the corresponding range or free-play path.
12 action
Re-install the affected control surface, then run a nominal preflight.
13 question
Did the nominal preflight pass without the
UNCALIBRATED failure? 14 action
The calibration failure is clear. Return the aircraft to service if all other required checks pass.
15 escalation
If the nominal preflight still reports
UNCALIBRATED, escalate to P2 Firmware Motors On Call with the affected surface, hardware version, EOL result, and preflight output. 16 escalation
If the failure does not include
ZIP_EXECUTIVE_V4_TEST_UNCALIBRATED and an affected wing or tail servo calibration alarm, escalate to P2 Firmware Motors On Call with the failure details. 17 escalation
If communication with the control-surface servo cannot be established after checking the connections and rerunning the EOL test, escalate to P2 Firmware Motors On Call with the affected surface, hardware version, connection checks, and complete EOL result.
Resolution note
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