Hide Raspberry Pi Low Voltage Warning (Config Flags)
To hide the Raspberry Pi’s low-voltage warning overlay, add avoid_warnings=1 to the active config.txt file and reboot. This changes what appears on screen; it does not fix low voltage or stop throttling. First identify the Pi model and power issue, then use the setting only if you still want the warning hidden.
A warning-free display can look reassuring, but it is not proof that the Pi is receiving enough power. Low voltage may cause throttling, instability, or unexpected resets. I treat the overlay as a useful symptom: find out why it appeared before choosing whether to suppress it.
The steps below help you check the power path, confirm which configuration file the Pi uses, apply the setting, and verify the result under a typical workload.
Planning: Identify the Pi Model, OS, and Undervoltage Cause
This first check establishes which Pi and operating system you have, what power supply and cable are connected, and whether the warning reflects a real power problem. The undervoltage threshold is approximately 4.63 V, with a ±5% tolerance, at the board’s supply input. Model and operating conditions affect behavior.
Start by noting the Pi model, its operating system version, the power supply’s rating, the cable, and any attached devices. USB drives, cameras, and other peripherals can add to the load. A supply that works for one model may not meet another model’s needs, so check the official power guidance for your exact Pi.
On a supported system, run:
vcgencmd get_throttled
The command reports current and historical throttling or undervoltage flags. It is a useful clue, not a voltage measurement. A historical flag can remain after a brief event, and a nonzero result deserves investigation even if the overlay is no longer visible.
| What you observe | What to check next |
|---|---|
| Warning appears during heavy work | Supply rating, cable condition, and load |
| Warning appears when a peripheral starts | Peripheral power draw and how it is powered |
get_throttled reports flags | Power path and behavior during load |
| No warning appears after a reboot | Historical flags and whether the same workload reproduces the issue |
The key step is to establish a baseline before changing the display setting. If the warning repeats, address the cause first.
Access and Clearances: Locate and Back Up the Active Boot Configuration
The active boot configuration is the config.txt file on the boot partition used by the running system. Current Raspberry Pi OS installations commonly use /boot/firmware/config.txt; older installations commonly use /boot/config.txt. Confirm the OS and mounted partition rather than editing a path from memory.
Check the OS version:
cat /etc/os-release
Then inspect the likely mount points:
findmnt /boot/firmware
findmnt /boot
A path that does not show a mounted filesystem may not be the active boot partition on your installation. Check the system’s layout before editing; do not create a new config.txt in a guessed location.
Once you identify the active file, make a backup. For example, if your active file is /boot/firmware/config.txt, use:
sudo cp -a /boot/firmware/config.txt /boot/firmware/config.txt.backup
For an older installation, replace that path with /boot/config.txt. The -a option preserves file attributes while copying. Keep the backup until you have rebooted and confirmed the system behaves as expected.
If the Pi will not boot after an edit, the backup gives you a way to restore the previous configuration. Confirm the path and backup before proceeding.
Execution: Add avoid_warnings=1 and Reboot
The avoid_warnings setting controls warning overlays, not the Pi’s power input. Set it to 1 on its own line in the global part of the active configuration file. Keep it outside conditional sections, which begin with entries such as [all] or a model-specific selector.
Open the confirmed file with a text editor. For the current common path:
sudo nano /boot/firmware/config.txt
For an older installation, use:
sudo nano /boot/config.txt
Add this line:
avoid_warnings=1
Place it in the global section, before any conditional section that might apply to the Pi. Do not add it inside an unrelated model-specific block. Save the file and reboot:
sudo reboot
After startup, the overlay should be suppressed. If it remains, check that you edited the active file, placed the setting correctly, and saved the change. Do not respond to a persistent power warning by repeatedly adding the same setting; investigate the power supply and connection.
Verification: Check Throttling and Power Stability Under Load
Verification means checking both that the display setting took effect and that the Pi remains stable when doing its normal work. A hidden overlay only confirms that the message is not being shown. It does not demonstrate that voltage is adequate or that throttling has stopped.
After reboot, run:
vcgencmd get_throttled
Then use the Pi as you normally would: start the services, peripherals, or workload that were active when the warning appeared. Run the command again while that work is underway. The command reports flags; it does not replace measuring voltage at the board under load.
If you see an undervoltage or throttling flag, treat it as unresolved even if the screen looks clean. Review the supply against the official specification for your model. Check that the cable is sound and suitable, and consider whether attached devices are drawing more power than the setup can provide. Where appropriate, power a high-draw peripheral separately using a suitable arrangement.
| Check | What it tells you | What it does not prove |
|---|---|---|
| Overlay is gone | The warning display is suppressed | That the Pi has enough power |
get_throttled shows flags | A current or past event was recorded | The exact cause or measured voltage |
| No flags during a typical workload | No reported flags were present in that check | That every workload or power condition is safe |
| Voltage measured under load | Voltage at the measurement point and time | Long-term stability under all conditions |
A clean display is not a power test. If instability, resets, or flags persist, restore the warning if useful and correct the power issue before relying on the system.
Diagnostic Examples: Decide Whether to Hide the Overlay
These examples describe common troubleshooting patterns, not measured case reports. They show how to separate the display change from the underlying fault. The same setting may be reasonable in a controlled setup, but repeated undervoltage should still lead to a power check.
In one typical pattern, a warning appears when a USB device starts. I would check the supply, cable, and peripheral load before editing the configuration. If the warning stops after the power arrangement is corrected, there is less reason to hide a useful alert.
In another pattern, an installation is used without a monitor, or a warning overlay disrupts a dedicated display. After checking the supply and reviewing get_throttled during the expected workload, an operator may choose to suppress the overlay. That choice should come with a plan to monitor power issues through other means.
A third pattern is a warning that disappears after reboot but leaves historical flags. That does not establish that the issue is fixed. Repeat the workload that first triggered the warning, inspect the status again, and check the power path if flags recur.
Conclusion: Hide the Message, Not the Evidence
avoid_warnings=1 is a presentation option, not an undervoltage remedy. Use it only after you have identified the active configuration file and considered the power supply, cable, and connected load. Recheck the Pi during representative use, and treat any undervoltage flags or instability as a problem to resolve.
The safest sequence is simple: diagnose, correct the power path, edit the confirmed file, reboot, and verify. Keep the backup so you can reverse the change.
FAQ: Raspberry Pi Low-Voltage Warning Settings
These answers distinguish the display setting from power diagnosis. The key point is that avoid_warnings=1 hides warning overlays; it does not raise voltage, stop throttling, or make an unsuitable supply safe.
Does avoid_warnings=1 fix undervoltage?
No. It suppresses warning overlays. Check the supply, cable, and connected load to address the cause.
Where should I put avoid_warnings=1?
Put it on its own line in the global section of the active config.txt, outside unrelated conditional sections.
Is the configuration file always /boot/firmware/config.txt?
No. Current Raspberry Pi OS commonly uses that path; older installations commonly use /boot/config.txt. Confirm the active boot partition first.
Do I need to reboot after editing?
Yes. Reboot after saving the file so the configuration change can take effect.
What does vcgencmd get_throttled show?
On supported systems, it reports current and historical throttling or undervoltage flags. It is not a voltage measurement.
What voltage triggers the low-voltage indication?
The documented threshold is approximately 4.63 V, with a ±5% tolerance, at the board’s supply input. Model and operating conditions matter.
Can I ignore a flag if the warning is hidden?
No. A hidden overlay does not clear a recorded event or prove stable power. Investigate recurring flags and instability.
Why does the warning appear when a peripheral starts?
The added load may expose a limitation in the supply, cable, or power arrangement. Check the exact Pi model’s supply guidance and assess the peripheral’s power needs.
Should I use the same power supply for every Raspberry Pi model?
No. Follow the official supply specification for the exact model. Do not assume a supply and cable suitable for one Pi will suit another.
How can I undo the setting?
Remove the avoid_warnings=1 line from the active file, save it, and reboot. If needed, restore the backup you made before editing.
(This article was written by one of our staff writers, Michael Holloway. Visit our Meet the Team page.)
