SD found, no FAT16/32 partition found

Hi all,

I bought an microSD module, (see attachments) and I am using an Arduino Uno.

I am trying to make it work. I used different sample codes but a partition is never found.

I connected it like this:

3v3 -> 3.3V
cs -> PIN 10
mosi -> PIN 11
clk -> PIN 13
miso -> PIN 12
gnd -> GND

This is the code I use at the moment:

  SD card test
This example shows how use the utility libraries on which the'
SD library is based in order to get info about your SD card.
Very useful for testing a card when you're not sure whether its working or not.
The circuit:
  * SD card attached to SPI bus as follows:
** MOSI - pin 11 on Arduino Uno/Duemilanove/Diecimila
** MISO - pin 12 on Arduino Uno/Duemilanove/Diecimila
** CLK - pin 13 on Arduino Uno/Duemilanove/Diecimila
** CS - depends on your SD card shield or module.
          Pin 4 used here for consistency with other Arduino examples

created  28 Mar 2011
by Limor Fried
modified 9 Apr 2012
by Tom Igoe
// include the SD library:
#include <SD.h>

// set up variables using the SD utility library functions:
Sd2Card card;
SdVolume volume;
SdFile root;

// change this to match your SD shield or module;
// Arduino Ethernet shield: pin 4
// Adafruit SD shields and modules: pin 10
// Sparkfun SD shield: pin 8
const int chipSelect = 10;   

void setup()
// Open serial communications and wait for port to open:
   while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only

  Serial.print("\nInitializing SD card...");
  // On the Ethernet Shield, CS is pin 4. It's set as an output by default.
  // Note that even if it's not used as the CS pin, the hardware SS pin
  // (10 on most Arduino boards, 53 on the Mega) must be left as an output
  // or the SD library functions will not work.
  pinMode(10, OUTPUT);     // change this to 53 on a mega

  // we'll use the initialization code from the utility libraries
  // since we're just testing if the card is working!
  if (!card.init(SPI_HALF_SPEED, chipSelect)) {
    Serial.println("initialization failed. Things to check:");
    Serial.println("* is a card is inserted?");
    Serial.println("* Is your wiring correct?");
    Serial.println("* did you change the chipSelect pin to match your shield or module?");
  } else {
   Serial.println("Wiring is correct and a card is present.");

  // print the type of card
  Serial.print("\nCard type: ");
  switch(card.type()) {
    case SD_CARD_TYPE_SD1:
    case SD_CARD_TYPE_SD2:

  // Now we will try to open the 'volume'/'partition' - it should be FAT16 or FAT32
  if (!volume.init(card)) {
    Serial.println("Could not find FAT16/FAT32 partition.\nMake sure you've formatted the card");

  // print the type and size of the first FAT-type volume
  uint32_t volumesize;
  Serial.print("\nVolume type is FAT");
  Serial.println(volume.fatType(), DEC);
  volumesize = volume.blocksPerCluster();    // clusters are collections of blocks
  volumesize *= volume.clusterCount();       // we'll have a lot of clusters
  volumesize *= 512;                            // SD card blocks are always 512 bytes
  Serial.print("Volume size (bytes): ");
  Serial.print("Volume size (Kbytes): ");
  volumesize /= 1024;
  Serial.print("Volume size (Mbytes): ");
  volumesize /= 1024;

  Serial.println("\nFiles found on the card (name, date and size in bytes): ");
  // list all files in the card with date and size | LS_DATE | LS_SIZE);

void loop(void) {

And this is the output I get:

Initializing SD card...Wiring is correct and a card is present.

Card type: SD2
Could not find FAT16/FAT32 partition.
Make sure you've formatted the card

Also, if i take the SD card out, it says there is no SD card. So that is working.

I formatted the SD card using Windows to FAT(Default), using Mac to MS-DOS(FAT), using the Mac Commandline to FAT32 and using the program SDFormatter.

I hope you can help me with this, it is starting to drive me crazy.

Thanks in advance!

  • BUMP *

Is there really no-one with an answer / solution to this, or with a similar problem?

It's driving me crazy right now ..



  • BUMP *

Is there really no-one with an answer / solution to this, or with a similar problem?

It's driving me crazy right now ..

The module you are trying to use is designed to work with 3.3V devices, The UNO is a 5v device. You will need to insert voltage level shifters between the SDcard module and your UNO. Or get a SDcard module that includes these shifters.

Like this one from AdaFruit:


Hello JeroenJK,

was this tip working? I have the same issue this time.



I have a SD card module with these level shifters, my problem was, USB gave me 4.6 V. After powering my circuit with extra power 5.1 V all worked well.