Dock Not Heating Aircraft Battery
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Applicable alarms (2)
HEATER_NO_COMMSTHERMAL_SERVICE_STATE_FAULTED
Likely outcomes — click to expand
Based on 0 missions where this alarm fired in the last
90 days
(for HEATER_NO_COMMS) as of 2026-10-13
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Related Search Phrases
Section titled “Related Search Phrases”This issue may also be described as battery not heating, Zip battery, or battery too cold.
Background
Section titled “Background”The Aircraft battery may not be heating for a number of reasons associated with the Dock’s Thermal System. These reasons include:
- Latch may not be retracted.
- PTC heater controller may be faulting.
- Evaporator Fan (Blower) may not be spinning.
- Heater may be unintentionally OFF.
We will walk through telemetry for each component here to identify a likely cause.
Troubleshooting Steps (Fleet Wrangler)
Section titled “Troubleshooting Steps (Fleet Wrangler)”graph TD
in-fleet-wrangler-is-the-latch-service{"<small><b>Step 1</b></small><br/>Question: In Fleet Wrangler, is the latch servi..."}
follow-the-guide-associated-with-the-la("<small><b>Step 2</b></small><br/>Reference: Follow the guide associated with the ...")
after-the-latch-state-is-retracted-is-t{"<small><b>Step 3</b></small><br/>Question: After the latch state is RETRACTED, i..."}
the-dock-may-return-to-service("<small><b>Step 4</b></small><br/>Reference: The Dock may return to service.")
in-fleet-wrangler-check-the-docks-deta{"<small><b>Step 5</b></small><br/>Question: In Fleet Wrangler, check the Dock's ..."}
restart-the-thermal-service["<small><b>Step 6</b></small><br/>Action: Restart the thermal service: 1. SSH i..."]
in-fleet-wrangler-check-the-docks-det-2{"<small><b>Step 7</b></small><br/>Question: In Fleet Wrangler, check the Dock's ..."}
power-cycle-the-dock-with-the-breakers["<small><b>Step 8</b></small><br/>Action: Power cycle the Dock with the breaker..."]
did-the-first-power-cycle-recover-the-asset{"<small><b>Step 9</b></small><br/>Question: Did the power cycle recover the asset?"}
power-cycle-the-dock-with-the-breakers-again["<small><b>Step 10</b></small><br/>Action: Power cycle the Dock with the breaker..."]
did-the-second-power-cycle-recover-the-asset{"<small><b>Step 11</b></small><br/>Question: Did the second power cycle recover th..."}
the-dock-may-return-to-service-after-power-cycle("<small><b>Step 12</b></small><br/>Reference: The Dock may return to service.")
escalate-after-second-power-cycle{{"<small><b>Step 13</b></small><br/>Escalation: Escalate to P2 Dock Hardware On Call."}}
continue-to-baraza-logs["<small><b>Step 14</b></small><br/>Action: Continue troubleshooting below using ..."]
in-fleet-wrangler-is-the-latch-service -->|Yes| in-fleet-wrangler-check-the-docks-deta
in-fleet-wrangler-is-the-latch-service -->|No| follow-the-guide-associated-with-the-la
follow-the-guide-associated-with-the-la --> after-the-latch-state-is-retracted-is-t
after-the-latch-state-is-retracted-is-t -->|Yes| the-dock-may-return-to-service
after-the-latch-state-is-retracted-is-t -->|No| in-fleet-wrangler-check-the-docks-deta
in-fleet-wrangler-check-the-docks-deta -->|Yes| restart-the-thermal-service
in-fleet-wrangler-check-the-docks-deta -->|No| in-fleet-wrangler-check-the-docks-det-2
restart-the-thermal-service --> in-fleet-wrangler-check-the-docks-det-2
in-fleet-wrangler-check-the-docks-det-2 -->|Yes| power-cycle-the-dock-with-the-breakers
in-fleet-wrangler-check-the-docks-det-2 -->|No| continue-to-baraza-logs
power-cycle-the-dock-with-the-breakers --> did-the-first-power-cycle-recover-the-asset
did-the-first-power-cycle-recover-the-asset -->|Yes| the-dock-may-return-to-service-after-power-cycle
did-the-first-power-cycle-recover-the-asset -->|No| power-cycle-the-dock-with-the-breakers-again
power-cycle-the-dock-with-the-breakers-again --> did-the-second-power-cycle-recover-the-asset
did-the-second-power-cycle-recover-the-asset -->|Yes| the-dock-may-return-to-service-after-power-cycle
did-the-second-power-cycle-recover-the-asset -->|No| escalate-after-second-power-cycle
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style did-the-first-power-cycle-recover-the-asset fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style power-cycle-the-dock-with-the-breakers-again fill:#dcfce7,stroke:#22c55e,color:#14532d
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style continue-to-baraza-logs fill:#dcfce7,stroke:#22c55e,color:#14532d Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
In Fleet Wrangler, is the latch service LATCH_SERVICE_STATE_RETRACTED or LATCH_SERVICE_STATE_SAFE_RETRACTED?
2 reference
Follow the guide associated with the latch state you see:
- LATCH_SERVICE_STATE_RETAINED
- LATCH_SERVICE_STATE_EMPTY
- LATCH_SERVICE_STATE_FAULTED
- LATCH_SERVICE_STATE_RETAINED
- LATCH_SERVICE_STATE_EMPTY
- LATCH_SERVICE_STATE_FAULTED
3 question
After the latch state is RETRACTED, is the issue resolved?
4 reference
The Dock may return to service.
5 question
In Fleet Wrangler, check the Dock's
Detailed Dock Status. Is the thermal service state set to THERMAL_SERVICE_STATE_FAULTED ? 6 action
Restart the thermal service:
1. SSH into the Dock (SSH into Dock).
2. Run
Complete these steps one time and if the problem reoccurs, continue to the next step.
1. SSH into the Dock (SSH into Dock).
2. Run
sudo systemctl restart thermal.service.Complete these steps one time and if the problem reoccurs, continue to the next step.
7 question
In Fleet Wrangler, check the Dock's
Detailed Dock Status. Is the HEATER_NO_COMMS alarm set? 8 action
Power cycle the Dock with the breakers to re-establish heater communication. For steps, see Power Cycle/Reset Tripped Dock Breaker.
9 question
Did the power cycle recover the asset?
10 action
Power cycle the Dock with the breakers one more time. For steps, see Power Cycle/Reset Tripped Dock Breaker.
11 question
Did the second power cycle recover the asset?
12 reference
The Dock may return to service.
13 escalation
Escalate to P2 Dock Hardware On Call.
14 action
Continue troubleshooting below using Baraza logs.
Resolution note
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Troubleshooting Steps (Baraza Logs)
Section titled “Troubleshooting Steps (Baraza Logs)”Check the logs in Baraza with the template “Thermal System Health” applied. Make sure the log time period spans the time period where the dock is trying to heat the vehicle battery but is unsuccessful.
graph TD
is-the-following-condition-true{"<small><b>Step 1</b></small><br/>Question: Is the following condition true: - t..."}
escalate-to-p2-dock-embedded-on-call{{"<small><b>Step 2</b></small><br/>Escalation: Escalate to P2 Dock Embedded On Call."}}
does-supply-temp-degc-rise-above-target{"<small><b>Step 3</b></small><br/>Question: Does thermal_diagnostics.component_f..."}
latch-is-not-retracted-send-redocking["<small><b>Step 4</b></small><br/>Action: Latch is not retracted and the therma..."]
is-zip-blower-freq-hz-greater-than-70{"<small><b>Step 5</b></small><br/>Question: Is thermal_diagnostics.component_fee..."}
blower-not-spinning-remove-replace-dock["<small><b>Step 6</b></small><br/>Action: The blower is not spinning as expecte..."]
is-heater-power-less-than-5{"<small><b>Step 7</b></small><br/>Question: The blower is operating nominally. Is..."}
heater-is-off-escalate-to-dock-hardware["<small><b>Step 8</b></small><br/>Action: The Aircraft battery heater is off. T..."]
thermal-system-degraded-replace-dock["<small><b>Step 9</b></small><br/>Action: Thermal system heating performance ha..."]
is-the-following-condition-true -->|Yes| does-supply-temp-degc-rise-above-target
is-the-following-condition-true -->|No| escalate-to-p2-dock-embedded-on-call
does-supply-temp-degc-rise-above-target -->|Yes| latch-is-not-retracted-send-redocking
does-supply-temp-degc-rise-above-target -->|No| is-zip-blower-freq-hz-greater-than-70
latch-is-not-retracted-send-redocking --> is-zip-blower-freq-hz-greater-than-70
is-zip-blower-freq-hz-greater-than-70 -->|Yes| is-heater-power-less-than-5
is-zip-blower-freq-hz-greater-than-70 -->|No| blower-not-spinning-remove-replace-dock
is-heater-power-less-than-5 -->|Yes| heater-is-off-escalate-to-dock-hardware
is-heater-power-less-than-5 -->|No| thermal-system-degraded-replace-dock
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style thermal-system-degraded-replace-dock 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 following condition true:
-
-
thermal_status.control_mode= HEAT AND thermal_diagnostics.component_control.heater_enabled is true 2 escalation
Escalate to P2 Dock Embedded On Call.
3 question
Does
thermal_diagnostics.component_feedback.supply_temp_degc rise above chager_command.battery_temperature_target? 4 action
Latch is not retracted and the thermal system cannot push air through the battery.
1. Send a redocking mission. If a redocking mission cannot be sent, the Aircraft must be manually removed from the Dock, reinserted, and manually retracted.
2. If
1. Send a redocking mission. If a redocking mission cannot be sent, the Aircraft must be manually removed from the Dock, reinserted, and manually retracted.
2. If
avg_pack_temperature is within +/-10% of battery_temperature_target 10 minutes after redocking, the problem is fixed. Otherwise continue to next step. 5 question
Is
thermal_diagnostics.component_feedback.zip_blower_freq_hz > 70 ? 6 action
The blower is not spinning as expected.
1. Remove and replace the Dock.
- Note this fault code as the likely cause of failure in the Issue Ticket and ship the faulty thermal system to the Roost c/o Marty Cowell.
1. Remove and replace the Dock.
- Note this fault code as the likely cause of failure in the Issue Ticket and ship the faulty thermal system to the Roost c/o Marty Cowell.
7 question
The blower is operating nominally. Is
thermal_system_power.zip_battery_air_heater.power_w < 5? 8 action
The Aircraft battery heater is off. This should not be the case when heating the battery. The thermal service is attempting to enable heat but the load switch is reporting no power draw, likely an open circuit.
1. Escalate to P2 Dock Hardware On Call.
1. Escalate to P2 Dock Hardware On Call.
9 action
Thermal system heating performance has degraded - likely due to a bad electrical connection with the PTC heater or a faulty PTC heater controller.
1. Remove and replace the Dock.
WORK ORDER TEMPLATE: Use Work Order Template #265: Replace Thermal Assembly on Dock.
- Note this fault code as the likely cause of failure in the Issue Ticket and ship the faulty thermal system to the Roost c/o Marty Cowell.
1. Remove and replace the Dock.
WORK ORDER TEMPLATE: Use Work Order Template #265: Replace Thermal Assembly on Dock.
- Note this fault code as the likely cause of failure in the Issue Ticket and ship the faulty thermal system to the Roost c/o Marty Cowell.
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