ERROR_SERVO_ROLL_RESISTANCE
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Applicable alarms (1)
ERROR_SERVO_ROLL_RESISTANCE
Likely outcomes — click to expand
Based on 43 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 occurs when high resistance is detected in the roll servo’s DC power path during preflight.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
is-the-servo-s-m5-connector-to-the-tail{"<small><b>Step 1</b></small><br/>Question: Is the servo’s M5 connector to the ta..."}
hand-tighten-m5-connector-and-apply-ne["<small><b>Step 2</b></small><br/>Action: Hand tighten M5 connector and apply n..."]
swap-the-aft-motor-assembly-update-the["<small><b>Step 3</b></small><br/>Action: Swap the Aft Motor Assembly. Update t..."]
perform-preflight-check-does-the-alarm{"<small><b>Step 4</b></small><br/>Question: Perform preflight check. Does the ala..."}
did-you-already-swap-the-aft-motor-ass{"<small><b>Step 5</b></small><br/>Question: Did you already swap the Aft Motor As..."}
this-is-likely-a-new-issue-escalate-to{{"<small><b>Step 6</b></small><br/>Escalation: This is likely a new issue. Escalate ..."}}
swap-the-aft-motor-assembly-update-the-2["<small><b>Step 7</b></small><br/>Action: Swap the Aft Motor Assembly. Update t..."]
after-performing-the-required-swap-red{"<small><b>Step 8</b></small><br/>Question: After performing the required swap, r..."}
this-is-likely-a-new-issue-escalate-to-2{{"<small><b>Step 9</b></small><br/>Escalation: This is likely a new issue. Escalate ..."}}
aircraft-can-be-cleared-for-service["<small><b>Step 10</b></small><br/>Action: Aircraft can be cleared for service."]
aircraft-can-be-cleared-for-service-2["<small><b>Step 11</b></small><br/>Action: Aircraft can be cleared for service."]
is-the-servo-s-m5-connector-to-the-tail -->|Yes| hand-tighten-m5-connector-and-apply-ne
is-the-servo-s-m5-connector-to-the-tail -->|No| swap-the-aft-motor-assembly-update-the
hand-tighten-m5-connector-and-apply-ne --> perform-preflight-check-does-the-alarm
swap-the-aft-motor-assembly-update-the --> perform-preflight-check-does-the-alarm
perform-preflight-check-does-the-alarm -->|Yes| did-you-already-swap-the-aft-motor-ass
perform-preflight-check-does-the-alarm -->|No| aircraft-can-be-cleared-for-service
did-you-already-swap-the-aft-motor-ass -->|Yes| this-is-likely-a-new-issue-escalate-to
did-you-already-swap-the-aft-motor-ass -->|No| swap-the-aft-motor-assembly-update-the-2
swap-the-aft-motor-assembly-update-the-2 --> after-performing-the-required-swap-red
after-performing-the-required-swap-red -->|Yes| this-is-likely-a-new-issue-escalate-to-2
after-performing-the-required-swap-red -->|No| aircraft-can-be-cleared-for-service-2
style is-the-servo-s-m5-connector-to-the-tail fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style hand-tighten-m5-connector-and-apply-ne fill:#dcfce7,stroke:#22c55e,color:#14532d
style swap-the-aft-motor-assembly-update-the fill:#dcfce7,stroke:#22c55e,color:#14532d
style perform-preflight-check-does-the-alarm fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style did-you-already-swap-the-aft-motor-ass fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style this-is-likely-a-new-issue-escalate-to fill:#fef3c7,stroke:#f59e0b,color:#78350f
style swap-the-aft-motor-assembly-update-the-2 fill:#dcfce7,stroke:#22c55e,color:#14532d
style after-performing-the-required-swap-red fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style this-is-likely-a-new-issue-escalate-to-2 fill:#fef3c7,stroke:#f59e0b,color:#78350f
style aircraft-can-be-cleared-for-service fill:#dcfce7,stroke:#22c55e,color:#14532d
style aircraft-can-be-cleared-for-service-2 fill:#dcfce7,stroke:#22c55e,color:#14532d Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Is the servo’s M5 connector to the tail node loose? Check for broken torque stripe on the M5 connector.
2 action
Hand tighten M5 connector and apply new torque stripe. Proceed to step 2.
3 action
Swap the Aft Motor Assembly. Update the ticket with findings and actions performed. For swap instructions refer to:
- UMM Remove Aft Motor Assembly
- UMM Install Aft Motor Assembly
Send the removed Aft Motor Assembly back to the Aviary (ATTN: @Kunal Verma) with a label indicating the ticket number.
- UMM Remove Aft Motor Assembly
- UMM Install Aft Motor Assembly
Send the removed Aft Motor Assembly back to the Aviary (ATTN: @Kunal Verma) with a label indicating the ticket number.
4 question
Perform preflight check. Does the alarm reappear?
5 question
Did you already swap the Aft Motor Assembly in step 1?
6 escalation
This is likely a new issue. Escalate to P2 Zip Hardware On Call and await engineering response.
7 action
Swap the Aft Motor Assembly. Update the ticket with findings and actions performed. For swap instructions refer to:
- UMM Remove Aft Motor Assembly
- UMM Install Aft Motor Assembly
Send the removed Aft Motor Assembly back to the Aviary (ATTN: @Kunal Verma) with a label indicating the ticket number.
- UMM Remove Aft Motor Assembly
- UMM Install Aft Motor Assembly
Send the removed Aft Motor Assembly back to the Aviary (ATTN: @Kunal Verma) with a label indicating the ticket number.
8 question
After performing the required swap, redo the preflight check. Does the alarm reappear?
9 escalation
This is likely a new issue. Escalate to P2 Zip Hardware On Call and await engineering response.
10 action
Aircraft can be cleared for service.
11 action
Aircraft can be cleared for service.
Resolution note
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