user28342: I just got the ADXL345 accelerometer module. I tried everything I could find online but I can't get it work. Here's how I connect the pins to the arduino uno:
ADXL345    ->     ARDUINO
  VCC               3.3V
  CS                3.3V
  GND               GND
  SDA               SDA
  SCL               SCL

I also use 2 10kOhm resistors from SDA, SCL to 3.3V on arduino. I tried both Adafruit and SparkFun ADXL345 libraries but it doesn't work. Using Adafruit library it says that no adxl345 is connected. I tried to connect SDO to 3.3V pin and then it stopped saying no adxl345 is connected but still didn't work (no x,y,z values displayed). Then I tried SparkFun library without connecting SDO to 3.3V (because it failed) and all I got was 0, 0, 0. I literally tried everything I could find from videos, tutorials, etc. I don't know why it doesn't work. What am I doing wrong? I already ordered the MPU6050. Is it any better?

user53507: As far as my experience goes you donot have to connect it to pulldown resistors. If using a 5v Arduino, simply connect it like:
VCC --> 5V  (Arduino)
GND --> GND (Arduino)
SDA --> A4 or SDA (Arduino Uno has dedicated I2C pins beside AREF pin)
SCL --> A5 or SCL
This is all you need. As although the ADXL345 is a 3.3v MEMS, its module comes with a 5v to 3.3v converter and also goes through its startup procedure (Refer datasheet) for you.
As for the library you can use this one here
Also you can refer this article for detailed usage here
And I hope next time you put in some more research and then buy a new part.

28342: <p>I just got the ADXL345 accelerometer module. I tried everything I could find online but I can't get it work. Here's how I connect the pins to the arduino uno:</p>

<pre><code>ADXL345    -&gt;     ARDUINO
  VCC               3.3V
  CS                3.3V
  GND               GND
  SDA               SDA
  SCL               SCL
</code></pre>

<p>I also use 2 10kOhm resistors from SDA, SCL to 3.3V on arduino. I tried both Adafruit and SparkFun ADXL345 libraries but it doesn't work. Using Adafruit library it says that no adxl345 is connected. I tried to connect SDO to 3.3V pin and then it stopped saying no adxl345 is connected but still didn't work (no x,y,z values displayed). Then I tried SparkFun library without connecting SDO to 3.3V (because it failed) and all I got was 0, 0, 0. I literally tried everything I could find from videos, tutorials, etc. I don't know why it doesn't work. What am I doing wrong? I already ordered the MPU6050. Is it any better?</p>
 53507: <p>As far as my experience goes you donot have to connect it to pulldown resistors. If using a 5v Arduino, simply connect it like:</p>
<p>VCC --&gt; 5V  (Arduino)<br />
GND --&gt; GND (Arduino)<br />
SDA --&gt; A4 or SDA (Arduino Uno has dedicated I2C pins beside AREF pin)<br />
SCL --&gt; A5 or SCL</p>
<p>This is all you need. As although the ADXL345 is a 3.3v MEMS, its module comes with a 5v to 3.3v converter and also goes through its startup procedure (<a href="https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL345.pdf" rel="nofollow noreferrer">Refer datasheet</a>) for you.<br />
As for the library you can use this one <a href="https://github.com/jarzebski/Arduino-ADXL345" rel="nofollow noreferrer">here</a><br />
Also you can refer this article for detailed usage <a href="http://www.jarzebski.pl/arduino/czujniki-i-sensory/3-osiowy-akcelerometr-adxl345.html" rel="nofollow noreferrer">here</a><br />
And I hope next time you put in some more research and then buy a new part.</p>
