UNSAFE_TO_CHARGE - /thruster_main.droid_battery_status
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Applicable alarms (1)
UNSAFE_TO_CHARGE
Likely outcomes — click to expand
Based on 11 missions where this alarm fired in the last 90 days as of 2026-10-13
Frequently co-occurring alarms (% of the 11 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”This is a summary alarm that indicates an off nominal condition is blocking the droid battery from charging.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
check-the-thruster-main-droid-battery-s{"<small><b>Step 1</b></small><br/>Question: Check the thruster_main.droid_battery..."}
overvoltage-escalate-to-p2-firmware-pow{{"<small><b>Step 2</b></small><br/>Escalation: Escalate to P2 Firmware Power On Call."}}
use-baraza-to-check-these-signals-brick["<small><b>Step 3</b></small><br/>Action: Use baraza to check these signals: - ..."]
are-they-above-or-below-5-degc{"<small><b>Step 4</b></small><br/>Question: Are they above or below 5 degC?"}
if-all-of-these-signals-are-above-5-deg["<small><b>Step 5</b></small><br/>Action: If all of these signals are above 5 d..."]
if-the-issue-persists-escalate-to-p2-fi{{"<small><b>Step 6</b></small><br/>Escalation: If the issue persists, escalate to P2..."}}
the-droid-battery-heater-should-be-tryi{{"<small><b>Step 7</b></small><br/>Escalation: The droid battery heater should be tr..."}}
overcurrent-escalate-to-p2-firmware-pow{{"<small><b>Step 8</b></small><br/>Escalation: Escalate to P2 Firmware Power On Call."}}
undervoltage-escalate-to-p2-firmware-po{{"<small><b>Step 9</b></small><br/>Escalation: Escalate to P2 Firmware Power On Call."}}
allow-battery-to-cool-below-50-degc["<small><b>Step 10</b></small><br/>Action: Allow battery to cool below 50 degC."]
overtemp-if-the-issue-persists-escalate{{"<small><b>Step 11</b></small><br/>Escalation: If the issue persists, escalate to P2..."}}
check-the-thruster-main-droid-battery-s -->|SW_BRICK_OVERVOLTAGE_WARNI...| overvoltage-escalate-to-p2-firmware-pow
check-the-thruster-main-droid-battery-s -->|SW_UNDERTEMP_WARNING, HW...| use-baraza-to-check-these-signals-brick
check-the-thruster-main-droid-battery-s -->|HW_OVERCURRENT_CHARGE| overcurrent-escalate-to-p2-firmware-pow
check-the-thruster-main-droid-battery-s -->|SW_BRICK_UNDERVOLTAGE_CRIT...| undervoltage-escalate-to-p2-firmware-po
check-the-thruster-main-droid-battery-s -->|SW_OVERTEMP_WARNING, SW_...| allow-battery-to-cool-below-50-degc
use-baraza-to-check-these-signals-brick --> are-they-above-or-below-5-degc
are-they-above-or-below-5-degc -->|Above 5degC| if-all-of-these-signals-are-above-5-deg
are-they-above-or-below-5-degc -->|Below 5degC| the-droid-battery-heater-should-be-tryi
if-all-of-these-signals-are-above-5-deg --> if-the-issue-persists-escalate-to-p2-fi
allow-battery-to-cool-below-50-degc --> overtemp-if-the-issue-persists-escalate
style check-the-thruster-main-droid-battery-s fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style overvoltage-escalate-to-p2-firmware-pow fill:#fef3c7,stroke:#f59e0b,color:#78350f
style use-baraza-to-check-these-signals-brick fill:#dcfce7,stroke:#22c55e,color:#14532d
style are-they-above-or-below-5-degc fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style if-all-of-these-signals-are-above-5-deg fill:#dcfce7,stroke:#22c55e,color:#14532d
style if-the-issue-persists-escalate-to-p2-fi fill:#fef3c7,stroke:#f59e0b,color:#78350f
style the-droid-battery-heater-should-be-tryi fill:#fef3c7,stroke:#f59e0b,color:#78350f
style overcurrent-escalate-to-p2-firmware-pow fill:#fef3c7,stroke:#f59e0b,color:#78350f
style undervoltage-escalate-to-p2-firmware-po fill:#fef3c7,stroke:#f59e0b,color:#78350f
style allow-battery-to-cool-below-50-degc fill:#dcfce7,stroke:#22c55e,color:#14532d
style overtemp-if-the-issue-persists-escalate fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Check the thruster_main.droid_battery_status message and follow the instructions below for the off_nominal bits that you see.
2 escalation
Escalate to P2 Firmware Power On Call.
3 action
Use baraza to check these signals:
- brick_heater_temperature.thermistor_brick1
- brick_heater_temperature.thermistor_brick3_afe
- brick_heater_temperature.thermistor_brick5
- brick_heater_temperature.thermistor_brick1
- brick_heater_temperature.thermistor_brick3_afe
- brick_heater_temperature.thermistor_brick5
4 question
Are they above or below 5 degC?
5 action
If all of these signals are above 5 degC, reboot the droid.
6 escalation
If the issue persists, escalate to P2 Firmware Power On Call.
7 escalation
The droid battery heater should be trying to heat the battery if it is below 30degC. If the temperatures remain below 5degC for more than 10 minutes, escalate to P2 Firmware Power On Call.
8 escalation
Escalate to P2 Firmware Power On Call.
9 escalation
Escalate to P2 Firmware Power On Call.
10 action
Allow battery to cool below 50 degC.
11 escalation
If the issue persists, escalate to P2 Firmware Power On Call.
Resolution note
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