@Rongzhong Li I edited the definition to 11 and re-uploaded the WriteInstinct.INO After that I uploaded OpenCat. The servo is plugged in position 11. When triggered with commands like "say hi" the head is moving. But when trying to calibrate "servo 0" nothing happens.

The head is moving now, but I can't calibrate it.

I switched to 11 and it's working now. Thanks for your help. 😃 The soldering looks good on 12 and 13. Can't see any reason why they should not be working. And it worked on 12 until I took off the head yesterday...

I tried without success. I switched the pins 12 and 13. But there are some differences in my settings according to your screenshot.

I found it. So I just switch position 12 and 13, then upload the WriteInstinct.INO?

@Rongzhong Li yes it worked on that slot before. Are there any tutorials on how to modify the pin definition? Sorry for the question, this are my first steps in the field of robotics and programming...

that's a fast reply, thank you. I tried the spare servo from the package and one other servo too. No reaction on both of them. The black wire is up. What I noticed is, when I connect it to the front left slot I can moved the servo by hand without any resistance, as if there is no power.