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Raspberry Pi shows no picture: green LED blink patterns and boot checks

Check the green LED. A steady flicker means it is reading the card, and a repeating blink pattern is an error code.

What the message means

The Pi shows a pattern of blinks for boot faults. No flicker at all means it cannot read the card or has no power.

Fix it in this order

  1. Check the red power LED is steady, then look at the green LED.
  2. Reseat the SD card and try another card with a fresh image.
  3. Use the HDMI port next to the power input on boards with two, and a good cable.
  4. Try another monitor or input.
  5. Look up the blink pattern for your Pi model in the official documentation.
  6. Use a better power supply.

Why it happens

The Pi starts from firmware and reads the operating system from the card. The green activity LED shows that reading, and when something fails the firmware can flash a pattern to say what. A steady flicker therefore means the card is being read, and no activity at all means no card was found or the board is not getting enough power.

The patterns and their meanings depend on the model and firmware version, so use the table in the official documentation for your board. A weak supply can also stop the boot in ways that look like a card fault.

If you see this, do this

You seeDo this
No green LED activityCard or image.
Pattern repeatsLook up the code for your model.

card corruption, power supply.

Last reviewed: November 2026. These are the usual causes and the order that finds them fastest. Test on your own board; clones and cables differ.

Why this happens

When a Raspberry Pi powers on, the first code to run is stored inside the chip and is not on the card. It looks for the next stage of boot files on the SD card, loads them, and then starts the operating system. The green activity LED lights when the card is being read. If that first stage cannot find usable boot files, or the board does not get enough voltage to run reliably, the screen stays black and the LED shows a pattern or nothing.

Many black-screen reports are not a boot failure at all. The board can start fine and simply not send a picture, for example because the monitor was off or on another input when the Pi powered up. The LED tells you which of the two situations you are in, so read it before you change anything else.

How to confirm the cause

  • Watch the green LED for the first 30 seconds after power is applied. Irregular flicker for a few seconds means the card is being read. No activity at all points to power or to a card that is not detected.
  • Measure the supply while the Pi is running, if your board has the test points marked TP1 and TP2. You want close to 5 V there. A reading well below that, or a power warning on screen, points to the supply or cable.
  • Remove every USB device and the camera or HAT. If the Pi now shows a picture, one of them was pulling the supply down.
  • Put the card in a computer and open the boot partition. If it is empty or unreadable, write the image again. If it has files, the card is fine and the display path is the next suspect.
  • Try another HDMI cable, another monitor input, and the port closest to the power connector on boards with two.

Worked example

These lines in the config file on the boot partition ask for a picture on HDMI even if the monitor was not ready at power-up. Edit them on a computer with the card inserted, then try again. Use them as a test, and remove them later if they cause trouble.

# config.txt on the boot partition of the card
hdmi_force_hotplug=1
hdmi_safe=1
# Boot, wait a minute, then check:
#  - picture appears  -> the display handshake was the problem
#  - still black, green LED flickers -> OS is booting, check cable/port
#  - still black, no green LED -> card, image or power

Common mistakes

  • Pulling the card out while the Pi is powered, then judging the result before a full power cycle.
  • Using a phone charger that is rated for fewer amps than the Pi model needs, or a thin cable that drops voltage.
  • Copying the image files onto the card by hand instead of writing the image with an imaging tool.
  • Assuming a black screen means a dead board when only the HDMI link failed.
  • Reading blink patterns from the wrong model’s table, since the codes differ between boards.

If this did not fix it

  • A fresh image on a different, known-good card. If this boots, the first card is worn or faulty.
  • The power supply and cable. Try a supply rated for your Pi model with a short, thick lead.
  • The firmware on the board. Some models need an updated boot loader before they start from certain media, and the official documentation lists which.