i2cRead failed:4 (MPU6050, adafruit motor shield, Arduino R3)

Hi,
I have a problem with "i2cRead failed:4"
I want to build self balance robot.
Works fine but after a few second I got i2cRead failed.

I read a lot about it, so:
-I have separate power for motors and arduino (Both from USB but other cables), I tried also 9V for Arduino and USB for motor/motors.
-Motor's GND are connected with Arduino GND.
-My motors are 5V with gear 1:120, max measured current with load was 0.15A.
-Wires for MPU6050 are about 6cm length.
-I tried other motors (unknown from toys).
-I put 100uF capacitor between motor's Vcc and GND.
-1kOhm resistors on SDA and SCL.
But nothing solved my problem.

Have you any other idea?

Thanks,
Muniek MG

You need to find out what the trouble is, as opposed to throwing "fixes" at the situation in the hope that something will stick.

Given "i2cRead failed:4"
What's going on there?
Isolate the trouble - Start with the I2C device and get consistent Reads. Then, connect the other circuitry till things fall apart again.

Without motors (just disconnected from motor shield) everything works.
Now I power motor shield with DC power supply (5V), connect only one motor and it seems to work better,
furthermore when I change motor with other (unknown) it starts to work perfectly.

I think it's problem with current but my power supply is 9V, 3.6A connected to YwRobot power mb
and then 5V to motor shield as a external power.

UP

http://www.petervis.com/Raspberry_PI/Breadboard_Power_Supply/YwRobot_Breadboard_Power_Supply.html
THAT is not going to be good for much (in the way of current).

5V 2.5A DC power supply, the same problem :confused:
Could be that my motors are too bad? Because one of my unknown motor works great.

“5V 2.5A DC power supply, the same problem”
I don’t know what that means. :///
Using that 5V supply instead of that Ywrobot thing or what?

My point previously was that that Ywrobot thing, cute as it is, won’t allow for lots of output current - regardless of the supply it runs from.

I've connected 5V, 2.5A power supply directly to motor shield.

Is the motor shield "Vin jumper" in or out?
Get out the voltmeter.

By Vin jumper you mean jumper for sharing power from Arduino board?
So, is out.

“Get out the voltmeter.” ← I don’t get it

MuniekMg, did you find the answer?