Raspberry Pi not reading the SD card? Fix it in 2 easy steps

Milan Stanojevic
by Milan Stanojevic
Deputy Editor
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  • Probably the most common error with Raspberry Pi is a corrupted SD card, mainly due to improper shutdown or power failures.
  • There is not much you can do when this happens, but we've listed an additional option besides the fresh re-install.
  • For other issues that you might have with your Raspberry Pi, visit our Raspberry Pi errors hub.
  • Also, we have a lot of useful guides in our Developer Tools section, so you should check it out.
raspberry pi not reading sd card

On the first boot, the Raspberry Pi needs an SD card with the OS mounted on it; otherwise, you can’t go any further.

Many Pi boards come with a microSD card with the NOOBS (New Out Of the Box Software) installer; of course, you can also have your own standalone image. Whichever method you use, it is recommended to use an 8GB for SD card or higher.

But what’s most important, is to use a reliable SD card manufacturer. Now, you might probably not know from the start whether you’ve picked the wrong one, but buying only from authorized suppliers and doing some research on recommended SD card brands for Pi might be helpful.

When booting, you will know that there’s a problem with the SD card if the red LED is blinking, while the green LED is not. Or, the green LED can blink regularly (3 to 8 times) to indicate that there’s a problem with the card.

How do I fix the Raspberry Pi SD card issues?

1. Mount a fresh OS image

  1. Format the SD card in another PC, using SDFormatter. (If the formatting fails, the card is broken.)
  2. Get a clean OS or image from here.
  3. Save and insert the card in your Raspberry Pi to see if it works.

This is the standard recommended solution to fix a faulty microSD card. However, users complained that the Pi fails to recognize the card all too frequently and that they have to re-install a fresh image over and over again.

It is very frustrating, which is why the next solution might be helpful, but only after a first successful first boot: namely to make a read-only copy of the OS on a USD stick or another media device.

2. Make a read-only copy of the SD cardread-only copy of sd card for raspberry pi

  1. Copy the Raspberry image to your SD card.
  2. Boot normally from the card, but don’t Expand filesystem. Set up time zone and international settings.
  3. Run sudo fdisk/ dev/mmcblk0 and press p to print the current partition table.
  4. Then enter the following commands:correct corrupted sd card
  5. Modify the /etc/fstab  as follows:how to fix sd card for raspberry
  6. Run sudo partprobe to recognize the partition.
  7. Format the new partition with sudo mkfs –type ext4 /dev/mmcblk0p3
  8. Reboot.

If you then need to make changes to the system, you can remount the read-only partitions with write access sudo mount -o remount, rw /dev/mmcblk0p2 .

Additional info

  1. Users have reported that their SD card was functional when inserted into another Raspberry Pi board – usually an older version than the one that didn’t boot. In the end, they solved the problem with a new card.
  2. Sometimes, just taking the SD card out and rebooting can fix the issue.
  3. It was also mentioned that the plastic holder of the SD card might have been the problem since some Pi version is very picky about these details.

We would like to have your intake on this matter, so drop us a line with any other solutions that you might have, in the comments section below.

FAQ: Read more about SD cards to use with Raspberry Pi

  • What kind of SD card does Raspberry Pi use?

A Raspberry Pi uses a microSD card. We recommend using a reliable microSD card. If you’re not sure what to choose, have a look at our 6 best waterproof SD cards guide.

  • What is the largest size SD card for Raspberry Pi?

The maximum size would be 32GB, but 8 GB or even 16 GB for a start should be just fine.

  • Can I use a 64GB SD card in Raspberry Pi?

Yes, you can use a 64GB SD card in Raspberry Pi, but you will have to format it with the exFAT filesystem.