Problem on Turning function, depth hold mode and Temp sensor

Hi, I finished assembled Blue ROV2 and testing it now. I have few issues now.

When I start it in the depth hold mode, the motors spin more and more quickly and it immediately sink to the bottom of water and once I change back to normal mode, it is getting okay.

All moving functions are working fine except CW and CCW turning. It is not moving properly when I give a commend. It seems 2 thrusters are turning wrong way.

Hi Hojinnim,

Let’s start with the CW and CCW issue. Have you set the motor directions as described here? You have to check motor directions and reverse thrusters as necessary during setup.

The first issue with depth hold might be caused by the second one, so let’s get that fixed first and see if the depth hold issue persists.



Please read this post to see if you should update your firmware.

You should also verify your motor directions are configured correctly.



Hi Rusty and Jacob.

Yes, I have checked the motor directions as described they are all correct directions and updated firmware already but still the turning functions are not working properly. When I turning it, some of thruster is turning wrong way.

Hi Hojinnim,

Okay, if you check the motor directions and they still turn the wrong direction, the you may have the wrong firmware frame type installed on the Pixhawk. Please make sure you are using the ‘vectored’ frame type.

Here’s a link to the most recent firmware file:


Hojinnim, I think you may have switched two thrusters and plugged them into the wrong outputs on the Pixhawk. Please verify that your motors are plugged in to the right outputs, as numbered here. If you look at the diagram, you can see that if you were to switch motors 2 and 3, forward and lateral movements would still work correctly, but then when you try to yaw, the motors’ thrust will cancel out. This would also be the case if you were to switch motors 1 and 4.



Here is an image portraying what I think could be your problem.


Hi Jacob and Rusty

Thanks for the comments form you guys. I have busy so far so I tried them today. I solve the issue with a Jacob’s comment. I swapped 2 and 3 on Pixawk and reverse spin on 2 and 3 as well. She is working fine now.