Dock Not Cooling Aircraft Battery
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Applicable alarms (1)
ZIP_EXECUTIVE_V4_BATTERY_TEMPERATURE_NOT_READY
Likely outcomes — click to expand
Based on 0 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.
Related Search Phrases
Section titled “Related Search Phrases”This issue may also be described as battery not cooling, Zip battery, or battery too hot.
Background
Section titled “Background”The Aircraft battery may not be cooling for a number of reasons associated with the Dock’s Thermal System. These reasons include:
- Latch may not be retracted.
- Compressor may be faulting.
- Evaporator Fan (Blower) may not be spinning.
- Condenser Fan may not be spinning.
- Heater may be unintentionally ON.
- Refrigerant may have leaked.
- Compressor vane may be stuck open.
We will walk through telemetry for each component 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..."}
latch-no-follow-guide("<small><b>Step 2</b></small><br/>Reference: Follow the guide associated with the ...")
latch-run-health-checks["<small><b>Step 3</b></small><br/>Action: Run a Health Checks mission."]
latch-health-checks-passed{"<small><b>Step 4</b></small><br/>Question: Did the Run Health Checks mission pass?"}
check-thermal-service-state-faulted{"<small><b>Step 5</b></small><br/>Question: In Fleet Wrangler, check the Dock’s ..."}
thermal-faulted-restart-service["<small><b>Step 6</b></small><br/>Action: Restart the thermal service: 1. SSH i..."]
thermal-restart-run-health-checks["<small><b>Step 7</b></small><br/>Action: Run a Health Checks mission."]
thermal-restart-health-checks-passed{"<small><b>Step 8</b></small><br/>Question: Did the Run Health Checks mission pass?"}
dock-may-return-to-service("<small><b>Step 9</b></small><br/>Reference: The Dock may return to service.")
check-compressor-no-comms{"<small><b>Step 10</b></small><br/>Question: In Fleet Wrangler, check the Dock’s ..."}
compressor-no-comms-power-cycle["<small><b>Step 11</b></small><br/>Action: Power cycle the Dock with the breaker..."]
compressor-no-comms-run-health-checks["<small><b>Step 12</b></small><br/>Action: Run a Health Checks mission."]
compressor-no-comms-health-checks-passed{"<small><b>Step 13</b></small><br/>Question: Did the Run Health Checks mission pass?"}
compressor-no-comms-return-to-service("<small><b>Step 14</b></small><br/>Reference: The Aircraft may return to service.")
compressor-no-comms-powercycled-more-than-3{"<small><b>Step 15</b></small><br/>Question: Have you power cycled more than 3 times?"}
compressor-no-comms-escalate-hardware-oncall("<small><b>Step 16</b></small><br/>Reference: Escalate to P2 Dock Hardware On Call.")
compressor-no-comms-begin-again("<small><b>Step 17</b></small><br/>Reference: Begin this troubleshooting process ag...")
check-compressor-fault{"<small><b>Step 18</b></small><br/>Question: In Fleet Wrangler, is the **COMPRESS..."}
compressor-fault-follow-guide["<small><b>Step 19</b></small><br/>Action: Continue troubleshooting by following..."]
continue-to-baraza-logs["<small><b>Step 20</b></small><br/>Action: Continue troubleshooting below using ..."]
in-fleet-wrangler-is-the-latch-service -->|Yes| check-thermal-service-state-faulted
in-fleet-wrangler-is-the-latch-service -->|No| latch-no-follow-guide
latch-no-follow-guide --> latch-run-health-checks
latch-run-health-checks --> latch-health-checks-passed
latch-health-checks-passed -->|Yes| dock-may-return-to-service
latch-health-checks-passed -->|No| check-thermal-service-state-faulted
check-thermal-service-state-faulted -->|Yes| thermal-faulted-restart-service
check-thermal-service-state-faulted -->|No| check-compressor-no-comms
thermal-faulted-restart-service --> thermal-restart-run-health-checks
thermal-restart-run-health-checks --> thermal-restart-health-checks-passed
thermal-restart-health-checks-passed -->|Yes| dock-may-return-to-service
thermal-restart-health-checks-passed -->|No| check-compressor-no-comms
check-compressor-no-comms -->|Yes| compressor-no-comms-power-cycle
check-compressor-no-comms -->|No| check-compressor-fault
compressor-no-comms-power-cycle --> compressor-no-comms-run-health-checks
compressor-no-comms-run-health-checks --> compressor-no-comms-health-checks-passed
compressor-no-comms-health-checks-passed -->|Yes| compressor-no-comms-return-to-service
compressor-no-comms-health-checks-passed -->|No| compressor-no-comms-powercycled-more-than-3
compressor-no-comms-powercycled-more-than-3 -->|Yes| compressor-no-comms-escalate-hardware-oncall
compressor-no-comms-powercycled-more-than-3 -->|No| compressor-no-comms-begin-again
check-compressor-fault -->|Yes| compressor-fault-follow-guide
check-compressor-fault -->|No| continue-to-baraza-logs
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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 action
Run a Health Checks mission.
4 question
Did the Run Health Checks mission pass?
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
1. SSH into the Dock (SSH into Dock).
2. Run
sudo systemctl restart thermal.service. 7 action
Run a Health Checks mission.
8 question
Did the Run Health Checks mission pass?
9 reference
The Dock may return to service.
10 question
In Fleet Wrangler, check the Dock’s
Detailed Dock Status. Is the COMPRESSOR_NO_COMMS alarm set? 11 action
Power cycle the Dock with the breakers to re-establish compressor communication. For steps, see Power Cycle/Reset Tripped Dock Breaker.
12 action
Run a Health Checks mission.
13 question
Did the Run Health Checks mission pass?
14 reference
The Aircraft may return to service.
15 question
Have you power cycled more than 3 times?
16 reference
Escalate to P2 Dock Hardware On Call.
17 reference
Begin this troubleshooting process again from the top.
18 question
In Fleet Wrangler, is the COMPRESSOR_FAULT alarm set?
19 action
Continue troubleshooting by following COMPRESSOR_FAULT.
20 action
Continue troubleshooting below using Baraza logs.
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 cool the vehicle battery but is unsuccessful.
graph TD
baraza-check-conditions{"<small><b>Step 1</b></small><br/>Question: Is one of the following conditions tr..."}
conditions-no-escalate-embedded{{"<small><b>Step 2</b></small><br/>Escalation: Escalate to P2 Dock Embedded On Call."}}
check-supply-temp{"<small><b>Step 3</b></small><br/>Question: Does thermal_diagnostics.component_f..."}
supply-temp-yes-redock["<small><b>Step 4</b></small><br/>Action: Latch is not retracted and the therma..."]
wait-after-redocking["<small><b>Step 5</b></small><br/>Action: Wait 10 minutes."]
check-pack-temperature-after-redocking{"<small><b>Step 6</b></small><br/>Question: Is avg_pack_temperature within +/-1..."}
baraza-dock-may-return-to-service("<small><b>Step 7</b></small><br/>Reference: The Dock may return to service.")
evaluate-compressor{"<small><b>Step 8</b></small><br/>Question: Evaluate the compressor. !image-2025..."}
compressor-fault-code-replace["<small><b>Step 9</b></small><br/>Action: **Fault Codes**: 1: DC Input Undervol..."]
compressor-freq-check{"<small><b>Step 10</b></small><br/>Question: The compressor is not faulted. Is th..."}
compressor-jammed-replace["<small><b>Step 11</b></small><br/>Action: The compressor may be jammed or stuck..."]
check-blower-freq{"<small><b>Step 12</b></small><br/>Question: The compressor is operating nominally..."}
blower-not-spinning-replace["<small><b>Step 13</b></small><br/>Action: The blower is not spinning as expecte..."]
check-condenser-fan-freq{"<small><b>Step 14</b></small><br/>Question: The blower is operating nominally. Is..."}
condenser-not-spinning-replace["<small><b>Step 15</b></small><br/>Action: The condenser fan is not spinning as ..."]
check-heater-power{"<small><b>Step 16</b></small><br/>Question: The condenser fan is operating nomina..."}
heater-on-escalate["<small><b>Step 17</b></small><br/>Action: The Aircraft battery heater is on. Th..."]
dock-model-check{"<small><b>Step 18</b></small><br/>Question: Is the Dock an EV3 Dock or an EV4 Dock?"}
thermal-degraded-replace-ev4-escalate{{"<small><b>Step 19</b></small><br/>Escalation: Escalate to P2 Dock Hardware On Call ..."}}
thermal-degraded-replace["<small><b>Step 20</b></small><br/>Action: Thermal system performance has degrad..."]
thermal-degraded-replace-older["<small><b>Step 21</b></small><br/>Action: Thermal system performance has degrad..."]
baraza-check-conditions -->|Yes| check-supply-temp
baraza-check-conditions -->|No| conditions-no-escalate-embedded
check-supply-temp -->|Yes| supply-temp-yes-redock
check-supply-temp -->|No| evaluate-compressor
supply-temp-yes-redock --> wait-after-redocking
wait-after-redocking --> check-pack-temperature-after-redocking
check-pack-temperature-after-redocking -->|Yes| baraza-dock-may-return-to-service
check-pack-temperature-after-redocking -->|No| evaluate-compressor
evaluate-compressor -->|Yes| compressor-fault-code-replace
evaluate-compressor -->|No| compressor-freq-check
compressor-freq-check -->|Yes| check-blower-freq
compressor-freq-check -->|No| compressor-jammed-replace
check-blower-freq -->|Yes| check-condenser-fan-freq
check-blower-freq -->|No| blower-not-spinning-replace
check-condenser-fan-freq -->|Yes| check-heater-power
check-condenser-fan-freq -->|No| condenser-not-spinning-replace
check-heater-power -->|Yes| heater-on-escalate
check-heater-power -->|No| dock-model-check
dock-model-check -->|EV3 Dock| thermal-degraded-replace
dock-model-check -->|EV4 Dock| thermal-degraded-replace-ev4-escalate
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style thermal-degraded-replace-older 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 one of the following conditions true:
-
-
-
-
-
thermal_status.control_mode= MAX_COOL AND thermal_diagnostics.component_feedback.compressor_freq_hz > 0-
thermal_status.control_mode= PID_COMPRESSOR_COOL AND thermal_diagnostics.component_feedback.compressor_freq_hz > 0-
thermal_status.control_mode= HEAT AND thermal_diagnostics.component_control.heater_enabled is true-
thermal_status.control_mode= HEAT_EXCHANGE_ONLY AND thermal_diagnostics.component_feedback.hx_fan_freq_hz > 0 2 escalation
Escalate to P2 Dock Embedded On Call.
3 question
Does
thermal_diagnostics.component_feedback.supply_temp_degc drop below chager_command.battery_temperature_target? 4 action
Latch is not retracted and the thermal system cannot push air through the battery.
Send a redocking mission. If a redocking mission cannot be sent, the Aircraft must be manually removed from the Dock, reinserted, and manually retracted.
Send a redocking mission. If a redocking mission cannot be sent, the Aircraft must be manually removed from the Dock, reinserted, and manually retracted.
5 action
Wait 10 minutes.
6 question
Is
avg_pack_temperature within +/-10% of battery_temperature_target? 7 reference
The Dock may return to service.
8 question
Evaluate the compressor.
Is
Is
thermal_diagnostics.component_feedback.compressor_fault_code temporarily any value other than 0? 9 action
Fault Codes:
1: DC Input Undervoltage - Controller PCB may be damaged.
2: DC Input Overvoltage - Controller PCB may be damaged.
5: High Current (Hardware) - Compressor may be jammed or stuck.
8: Phase Loss or Imbalance - Compressor may be jammed or stuck.
1. Assign WO on Tower: Remove and Replace Dock on Tower
2. EV3 Assign WO on Dock: Replace Thermal Assembly on Dock
3. EV4 Assign WO on Dock: Replace Thermal System on EV4 Dock
- Note the fault code as the likely cause of failure in the Issue Ticket and ship the faulty thermal system to the coop atn: P2-Dock-Hardware-On-Call.
1: DC Input Undervoltage - Controller PCB may be damaged.
2: DC Input Overvoltage - Controller PCB may be damaged.
5: High Current (Hardware) - Compressor may be jammed or stuck.
8: Phase Loss or Imbalance - Compressor may be jammed or stuck.
1. Assign WO on Tower: Remove and Replace Dock on Tower
2. EV3 Assign WO on Dock: Replace Thermal Assembly on Dock
3. EV4 Assign WO on Dock: Replace Thermal System on EV4 Dock
- Note the fault code as the likely cause of failure in the Issue Ticket and ship the faulty thermal system to the coop atn: P2-Dock-Hardware-On-Call.
10 question
The compressor is not faulted.
Is
Is
thermal_diagnostics.component_feedback.compressor_freq_hz reaching the same value (+/-10%) as thermal_diagnostics.component_control.commanded_compressor_frequency_hz within 4 minutes of command? 11 action
The compressor may be jammed or stuck.
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 coop 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 coop c/o Marty Cowell.
12 question
The compressor is operating nominally.
Is
Is
thermal_diagnostics.component_feedback.zip_blower_freq_hz > 70 ? 13 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 coop 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 coop c/o Marty Cowell.
14 question
The blower is operating nominally.
Is
Is
thermals_diagnostics.compoenent_feedback.condenser_fan_freq_hz > 150 ? 15 action
The condenser fan 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 coop 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 coop c/o Marty Cowell.
16 question
The condenser fan is operating nominally.
Is
Is
thermal_system_power.zip_battery_air_heater.power_w > 5 ? 17 action
The Aircraft battery heater is on. This should not be the case when cooling the battery.
1. Escalate to P2 Dock Embedded On Call.
1. Escalate to P2 Dock Embedded On Call.
18 question
Is the Dock an EV3 Dock or an EV4 Dock?
19 escalation
Escalate to P2 Dock Hardware On Call to decide on next steps.
20 action >=2026.15
Thermal system performance has degraded - likely due to either a refrigerant leak or a stuck compressor vane.
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 coop 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 coop c/o Marty Cowell.
21 action <=2026.09
Thermal system performance has degraded - likely due to either a refrigerant leak or a stuck compressor vane.
1. Remove and replace the Dock.
WORK ORDER TEMPLATE: Use 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 coop c/o Marty Cowell.
1. Remove and replace the Dock.
WORK ORDER TEMPLATE: Use 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 coop c/o Marty Cowell.
Resolution note
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