BLOWER_UNEXPECTED_CONTROL_STATE
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Applicable alarms (1)
BLOWER_UNEXPECTED_CONTROL_STATE
Likely outcomes — click to expand
Based on 355 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 2 ZERP issues filed on these missions)
Frequently replaced parts
| Part | P/N | Removals |
|---|---|---|
| ASSY, SPOOL AND LINE, DOCKING FIN, AIRCRAFT, P2 | 48477 | 4 |
Frequently co-occurring alarms (% of the 355 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This alarm is published by the blower motor driver, this driver is responsible for controlling the motor that cools the NVIDIA Orin SOM. The blower motor is plugged into the compute board.
BLOWER_UNEXPECTED_CONTROL_STATE means that the motor driver chip is in an unexpected state and probably isn’t controlling the motor properly.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
is-this-the-first-time-this-alarm-has-o{"<small><b>Step 1</b></small><br/>Question: Is this the first time this alarm has..."}
power-cycle-the-aircraft-power-cycle-ai["<small><b>Step 2</b></small><br/>Action: Power cycle the aircraft: Power Cycl..."]
perform-preflight["<small><b>Step 3</b></small><br/>Action: Perform preflight."]
is-this-issue-resolved{"<small><b>Step 4</b></small><br/>Question: Is this issue resolved?"}
aircraft-can-return-to-service["<small><b>Step 5</b></small><br/>Action: Aircraft can return to service"]
inspect-the-compute-board-for-steps-s-2["<small><b>Step 6</b></small><br/>Action: Inspect the compute board. For steps,..."]
was-any-damage-found-on-the-compute-a-b{"<small><b>Step 7</b></small><br/>Question: Was any damage found on the compute A..."}
replace-the-board-for-steps-see-umm-rem["<small><b>Step 8</b></small><br/>Action: Replace the board. For steps, see: 1...."]
escalate-to-p2-avionics-hardware-on-cal{{"<small><b>Step 9</b></small><br/>Escalation: Escalate to P2 Avionics Hardware On C..."}}
inspect-the-compute-board-for-steps-see["<small><b>Step 10</b></small><br/>Action: Inspect the compute board. For steps,..."]
was-any-damage-found-on-the-compute-a-2{"<small><b>Step 11</b></small><br/>Question: Was any damage found on the compute A..."}
replace-the-compute-board-for-steps-see["<small><b>Step 12</b></small><br/>Action: Replace the Compute Board. For steps,..."]
escalate-to-p2-avionics-hardware-on-c-2{{"<small><b>Step 13</b></small><br/>Escalation: Escalate to P2 Avionics Hardware On C..."}}
is-this-the-first-time-this-alarm-has-o -->|Yes| power-cycle-the-aircraft-power-cycle-ai
is-this-the-first-time-this-alarm-has-o -->|No| inspect-the-compute-board-for-steps-see
power-cycle-the-aircraft-power-cycle-ai --> perform-preflight
perform-preflight --> is-this-issue-resolved
is-this-issue-resolved -->|Yes| aircraft-can-return-to-service
is-this-issue-resolved -->|No| inspect-the-compute-board-for-steps-s-2
inspect-the-compute-board-for-steps-s-2 --> was-any-damage-found-on-the-compute-a-b
was-any-damage-found-on-the-compute-a-b -->|Yes| replace-the-board-for-steps-see-umm-rem
was-any-damage-found-on-the-compute-a-b -->|No| escalate-to-p2-avionics-hardware-on-cal
inspect-the-compute-board-for-steps-see --> was-any-damage-found-on-the-compute-a-2
was-any-damage-found-on-the-compute-a-2 -->|Yes| replace-the-compute-board-for-steps-see
was-any-damage-found-on-the-compute-a-2 -->|No| escalate-to-p2-avionics-hardware-on-c-2
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style power-cycle-the-aircraft-power-cycle-ai fill:#dcfce7,stroke:#22c55e,color:#14532d
style perform-preflight fill:#dcfce7,stroke:#22c55e,color:#14532d
style is-this-issue-resolved fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style aircraft-can-return-to-service fill:#dcfce7,stroke:#22c55e,color:#14532d
style inspect-the-compute-board-for-steps-s-2 fill:#dcfce7,stroke:#22c55e,color:#14532d
style was-any-damage-found-on-the-compute-a-b fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style replace-the-board-for-steps-see-umm-rem fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-to-p2-avionics-hardware-on-cal fill:#fef3c7,stroke:#f59e0b,color:#78350f
style inspect-the-compute-board-for-steps-see fill:#dcfce7,stroke:#22c55e,color:#14532d
style was-any-damage-found-on-the-compute-a-2 fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style replace-the-compute-board-for-steps-see fill:#dcfce7,stroke:#22c55e,color:#14532d
style escalate-to-p2-avionics-hardware-on-c-2 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 this the first time this alarm has occurred?
2 action
Power cycle the aircraft: Power Cycle Aircraft.
3 action
Perform preflight.
4 question
Is this issue resolved?
5 action
Aircraft can return to service
6 action
Inspect the compute board. For steps, see UMM: Inspect Flight Compute Assembly (FCA).
7 question
Was any damage found on the compute A blower assembly, and/or any other area of the compute board?
8 action
Replace the board. For steps, see:
1. UMM: Remove Flight Compute Assembly (FCA)
2. UMM: Install Flight Compute Assembly (FCA)
1. UMM: Remove Flight Compute Assembly (FCA)
2. UMM: Install Flight Compute Assembly (FCA)
9 escalation
Escalate to P2 Avionics Hardware On Call.
10 action
Inspect the compute board. For steps, see UMM: Inspect Flight Compute Assembly.
11 question
Was any damage found on the compute A blower assembly, and/or any other area of the compute board?
12 action
Replace the Compute Board. For steps, see:
1. UMM: Remove Flight Compute Assembly (FCA)
2. UMM: Install Flight Compute Assembly (FCA)
1. UMM: Remove Flight Compute Assembly (FCA)
2. UMM: Install Flight Compute Assembly (FCA)
13 escalation
Escalate to P2 Avionics Hardware On Call.
Resolution note
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Example ZipMissionLog
Section titled “Example ZipMissionLog”{ "status": "ZIP_MISSION_STATUS_ENDED_IN_FAILURE", "asset_id": "p2-zip-371", "dock_ids": [ "p2-dock-84" ], "droid_id": "p2-droid-499", "timestamp": "2025-05-07T19:41:43.781Z", "flight_ids": [ "P2F_65AB1116D7C1594C" ], "mission_id": "P2M_65AB11142DC00000", "ibit_status": [], "capabilities": { "can_dock": "CAPABILITY_STATUS_DISABLED", "can_avoid": "CAPABILITY_STATUS_UNSPECIFIED", "can_hover": "CAPABILITY_STATUS_AVAILABLE", "can_cruise": "CAPABILITY_STATUS_AVAILABLE", "can_launch": "CAPABILITY_STATUS_FAILED", "can_deliver": "CAPABILITY_STATUS_DISABLED", "can_transit": "CAPABILITY_STATUS_AVAILABLE", "has_package": "CAPABILITY_STATUS_DISABLED", "can_failover": "CAPABILITY_STATUS_UNSPECIFIED", "can_paraland": "CAPABILITY_STATUS_DISABLED", "is_on_ground": "CAPABILITY_STATUS_DISABLED", "are_motors_off": "CAPABILITY_STATUS_AVAILABLE", "can_deconflict": "CAPABILITY_STATUS_UNSPECIFIED", "can_spin_motors": "CAPABILITY_STATUS_DISABLED", "is_droid_stowed": "CAPABILITY_STATUS_DISABLED", "can_perform_ibit": "CAPABILITY_STATUS_AVAILABLE", "can_control_droid": "CAPABILITY_STATUS_AVAILABLE", "can_control_winch": "CAPABILITY_STATUS_UNSPECIFIED", "is_droid_lid_open": "CAPABILITY_STATUS_DISABLED", "is_compute_healthy": "CAPABILITY_STATUS_UNSPECIFIED", "is_crossfire_alive": "CAPABILITY_STATUS_DISABLED", "is_droid_in_portal": "CAPABILITY_STATUS_AVAILABLE", "can_gnc_spin_motors": "CAPABILITY_STATUS_DISABLED", "is_in_dock_corridor": "CAPABILITY_STATUS_DISABLED", "is_retained_on_dock": "CAPABILITY_STATUS_AVAILABLE", "has_passed_all_ibits": "CAPABILITY_STATUS_DISABLED", "is_retracted_on_dock": "CAPABILITY_STATUS_AVAILABLE", "is_transit_completed": "CAPABILITY_STATUS_DISABLED", "can_transit_nominally": "CAPABILITY_STATUS_UNSPECIFIED", "is_cut_line_completed": "CAPABILITY_STATUS_UNSPECIFIED", "is_delivery_completed": "CAPABILITY_STATUS_DISABLED", "is_take_off_completed": "CAPABILITY_STATUS_DISABLED", "can_transit_with_droid": "CAPABILITY_STATUS_UNSPECIFIED", "is_call_home_completed": "CAPABILITY_STATUS_UNSPECIFIED", "can_reach_mission_goals": "CAPABILITY_STATUS_AVAILABLE", "is_dock_motion_completed": "CAPABILITY_STATUS_DISABLED", "is_lower_droid_completed": "CAPABILITY_STATUS_DISABLED", "is_raise_droid_completed": "CAPABILITY_STATUS_DISABLED", "can_droid_lower_to_portal": "CAPABILITY_STATUS_DISABLED", "are_diagnostic_ibits_reset": "CAPABILITY_STATUS_DISABLED", "can_droid_raise_from_portal": "CAPABILITY_STATUS_AVAILABLE", "can_receive_delivery_mission": "CAPABILITY_STATUS_AVAILABLE", "has_received_pending_mission": "CAPABILITY_STATUS_DISABLED", "is_take_off_time_window_open": "CAPABILITY_STATUS_AVAILABLE", "can_droid_execute_motion_cmds": "CAPABILITY_STATUS_UNSPECIFIED", "has_received_delivery_mission": "CAPABILITY_STATUS_DISABLED", "is_crossfire_disarm_requested": "CAPABILITY_STATUS_DISABLED", "is_diagnostic_abort_requested": "CAPABILITY_STATUS_DISABLED", "is_performing_partial_takeoff": "CAPABILITY_STATUS_DISABLED", "are_diagnostic_ibits_completed": "CAPABILITY_STATUS_DISABLED", "can_receive_reposition_mission": "CAPABILITY_STATUS_AVAILABLE", "is_software_download_completed": "CAPABILITY_STATUS_DISABLED", "has_received_reposition_mission": "CAPABILITY_STATUS_DISABLED", "is_crossfire_gnc_mode_requested": "CAPABILITY_STATUS_DISABLED", "is_crossfire_paraland_requested": "CAPABILITY_STATUS_DISABLED", "is_delivery_hydration_completed": "CAPABILITY_STATUS_DISABLED", "can_communicate_with_remote_pilot": "CAPABILITY_STATUS_AVAILABLE", "is_winch_emergency_hold_completed": "CAPABILITY_STATUS_UNSPECIFIED", "is_emergency_lower_droid_completed": "CAPABILITY_STATUS_UNSPECIFIED" }, "failure_summaries": [ "gps_timestamp": 1746042167544960000, "error_report": { "primary_unique_error_id": "ERR_123456", "errors": { "ERR_123456": { "code": 0x00010005, "message": "CanLaunch failed", "gps_timestamp": 173651165380000000, "unix_timestamp": 1024658498.45, "unique_id": "ERR_123456", "related_alarm_summaries": [{ "relation_type": "RelationType::CAUSED_BY", "alarm": { "alarm_id": 4, "identifier": "/compute_a.som_blower.status", "name": "BLOWER_UNEXPECTED_CONTROL_STATE", "alarm_namespace": "alarms", } }] } } }, "executive_task": "RunPreliminaryChecks", "flight_id": "P2F_65AB1116D7C1594C", "droid_status": { "lid_open": false, "behaviors": [], "motion_state": "", "battery_status": { "pack_current": 1.2839198, "pack_voltage": 19.84253, "state_of_charge": 0.7585616, "unsafe_to_charge": false, "unsafe_to_deploy": false, "unsafe_to_operate": false, "ms_since_relaxation": "182098", "requires_maintenance": false }, "capability_map": {}, "droid_asset_id": "p2-droid-499", "is_finger_safe": false, "current_executive_id": { "step_id": "1", "task_id": "8", "mission_id": "P2M_1AA5EDA994800000", "sequence_id": "15475" }, "safety_system_status": "DROID_SAFETY_SYSTEM_STATUS_NOT_READY", "current_command_status": "DROID_COMMAND_STATUS_COMPLETED", "current_command_string": "Portal (\"LOWER_TO_PORTAL\")", "message_injection_state": { "metadata": "", "is_running": false, "config_path": "" }, "droid_parachute_deploy_reason": "DROID_PARACHUTE_DEPLOY_UNSPECIFIED" }, "flight_status": "FLIGHT_STATUS_FAILED", "winch_cutter_state": "WINCH_CUTTER_STATE_UNARMED", "active_alarms": [ { "identifier": "/tail_bridge.comm_status", "alarm_summaries": [ { "name": "RS485_SERVO_TAIL_STBD_FWD_SIGNAL_QUALITY_OFF_NOMINAL", "alarm_id": 0, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "off_nominals" }, { "name": "RS485_SERVO_TAIL_PORT_FWD_SIGNAL_QUALITY_OFF_NOMINAL", "alarm_id": 1, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "off_nominals" }, { "name": "RS485_SERVO_ROLL_SIGNAL_QUALITY_OFF_NOMINAL", "alarm_id": 2, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "off_nominals" }, { "name": "RS485_SERVO_TILT_SIGNAL_QUALITY_OFF_NOMINAL", "alarm_id": 3, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "off_nominals" }, { "name": "RS485_SERVO_TAIL_STBD_FWD_LINK_FAULT", "alarm_id": 0, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" }, { "name": "RS485_SERVO_TAIL_PORT_FWD_LINK_FAULT", "alarm_id": 1, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" }, { "name": "RS485_SERVO_ROLL_LINK_FAULT", "alarm_id": 2, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" }, { "name": "RS485_SERVO_TILT_LINK_FAULT", "alarm_id": 3, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" } ] }, { "identifier": "zip_executive.executive_status", "alarm_summaries": [ { "name": "ZIP_MOTOR_CONTROL_UNINITIALIZED", "alarm_id": 18, "severity": "ALARM_WARNING", "report_id": "", "visibility": "MAINTENANCE", "alarm_namespace": "alarms" } ] }, { "identifier": "mic_array_summary", "alarm_summaries": [ { "name": "ACOUSTIC_PROBES_DEGRADED", "alarm_id": 0, "severity": "ALARM_INFO", "report_id": "", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" } ] }, { "identifier": "service_health_monitor.health", "alarm_summaries": [ { "name": "SERVICE_RESTARTED", "alarm_id": 0, "severity": "ALARM_INFO", "report_id": "p2-zip-371-service_health_monitor.alarm_report-1746646143.29986-0", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" }, { "name": "SERVICE_NOT_ACTIVE", "alarm_id": 1, "severity": "ALARM_INFO", "report_id": "p2-zip-371-service_health_monitor.alarm_report-1746643615.5932901-1", "visibility": "DEVELOPMENT", "alarm_namespace": "alarms" } ] } ], "occupied_bay_ids": [ "bay_8550db1c-76d5-46b4-bea8-47fec5924a0b" ], "proto_build_info": { "winch": { "app": { "git_sha": "d9d5887fdf9c6947aa861274e3421b349976915e", "has_uncommitted_changes": true }, "boot": { "git_sha": "bbb73bacd0e169086df33ac252b119556d265b8e", "has_uncommitted_changes": false } }, "distro_a": { "app": { "git_sha": "d9d5887fdf9c6947aa861274e3421b349976915e", "has_uncommitted_changes": true }, "boot": { "git_sha": "bbb73bacd0e169086df33ac252b119556d265b8e", "has_uncommitted_changes": false } }, "distro_b": { "app": { "git_sha": "d9d5887fdf9c6947aa861274e3421b349976915e", "has_uncommitted_changes": true }, "boot": { "git_sha": "bbb73bacd0e169086df33ac252b119556d265b8e", "has_uncommitted_changes": false } }, "zip_linux_sha": "3e736e17027ed2bd2917470568247e3f2a0aae7e", "flight_systems_sha": "d9d5887fdf9c6947aa861274e3421b349976915e", "compute_b_zip_linux_sha": "3e736e17027ed2bd2917470568247e3f2a0aae7e", "compute_b_flight_systems_sha": "d9d5887fdf9c6947aa861274e3421b349976915e" }, "software_config_status": { "config_state": "CONFIG_STATE_UNSPECIFIED", "release_name": "fsw-2025.15.rc15", "configuration_id": "46d69824-fd0d-4d49-8364-f43133e66776" }, "message_injection_state": { "is_running": false }, "parachute_deploy_reason": "PARACHUTE_DEPLOY_UNSPECIFIED", "winch_cutter_deploy_reason": "WINCH_CUT_UNSPECIFIED", "droid_parachute_deploy_reason": "DROID_PARACHUTE_DEPLOY_UNSPECIFIED", "mission_status_unix_timestamps": { "ZIP_MISSION_STATUS_FAILED": 1746646903.53002, "ZIP_MISSION_STATUS_ACCEPTED": 1746646883.17058, "ZIP_MISSION_STATUS_ENDED_IN_FAILURE": 1746646903.53017 },}Did this guide help you get unblocked?
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