Raspberry Pi Shutdown Indicator LED

[JanKoopmans]

? Raspberry Pi Shutdown Indicator LED using GPIO22 (OpenPlotter + MacArthur HAT)
For those running OpenPlotter on a Raspberry Pi 5 with a MacArthur HAT:
I've added a simple but super useful status LED to one of the GPIO pins. The LED indicates whether the Pi is still running. After issuing a

Code:

sudo shutdown now

, the LED turns off — so I know it's safe to cut the main power to the boat.

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✅ What it does

• ? LED ON = Raspberry Pi is running
  
• ⚫ LED OFF = Raspberry Pi has shut down cleanly → you can turn off the boat’s main power
  

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? What you need

• 1x green LED
  
• 1x 220 Ω resistor
  
• Jumper wires or Dupont cables
  
• A free GPIO pin (I used GPIO22 = physical pin 15)
  
• Raspberry Pi 5 with OpenPlotter and MacArthur HAT
  

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? Wiring
Connect your LED as follows:
less
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Code:

GPIO22 (pin 15) ──[220Ω]──>|── GND (pin 6)
                          LED

• The long leg of the LED (anode) goes to the resistor
  
• The short leg (cathode) goes to ground
  

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⚙️ Software setup with

Code:

systemd

1. Turn on the LED at boot
Create the script:
bash
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Code:

sudo nano /usr/local/bin/led_on.py

Content:
python
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Code:

#!/usr/bin/env python3
from gpiozero import LED
import time

led = LED(22)
led.on()

while True:
    time.sleep(60)

Make it executable:
bash
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Code:

sudo chmod +x /usr/local/bin/led_on.py

Create a systemd service:
bash
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Code:

sudo nano /etc/systemd/system/boot-led.service

Content:
ini
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Code:

[Unit]
Description=Turn on LED at boot
After=multi-user.target

[Service]
ExecStart=/usr/bin/python3 /usr/local/bin/led_on.py
Restart=always

[Install]
WantedBy=multi-user.target

Enable it:
bash
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Code:

sudo systemctl enable boot-led.service
sudo systemctl start boot-led.service

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2. Turn off the LED during shutdown
Create the script:
bash
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Code:

sudo nano /usr/local/bin/led_off.py

Content:
python
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Code:

#!/usr/bin/env python3
from gpiozero import LED

led = LED(22)
led.off()

Make it executable:
bash
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Code:

sudo chmod +x /usr/local/bin/led_off.py

Create the shutdown service:
bash
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Code:

sudo nano /etc/systemd/system/led-off.service

Content:
ini
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Code:

[Unit]
Description=Turn off LED at shutdown
DefaultDependencies=no
Before=shutdown.target

[Service]
ExecStart=/usr/bin/python3 /usr/local/bin/led_off.py
Type=oneshot

[Install]
WantedBy=shutdown.target

Enable the shutdown service:
bash
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Code:

sudo systemctl enable led-off.service

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✅ Result
Your LED now gives you clear visual feedback:
Pi State
LEDRunning
? ON
Shut down
⚫ OFF
Safe to power off?
✅ Yes, when LED is OFF

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ℹ️ Notes

• Tested on Raspberry Pi 5 + MacArthur HAT + OpenPlotter
  
• GPIO22 was free in my setup (double-check your own!)
  
• The LED is green, powered via GPIO with a 220 Ω resistor — safe and bright