Servo. Motor proplems

Hi guys... I have just bought a new servo motor... When I tried to test it. It keep making sound like ziiii and not move... So what does this mean

And I think the proplem is that the gears in it is not connected right... And then this sound is made

Show us a good schematic of your proposed circuit.
Show us a good image of your ‘actual’ wiring.
Give links to components.

In the Arduino IDE, use Ctrl T or CMD T to format your code then copy the complete sketch.

Use the </> icon from the ‘reply menu’ to attach the copied sketch.

With most hobby servos (not powered) you can manually move the horn CW and CCW, can you ?

You can usually take the gear box apart to see if there is something wrong with the meshing.

If you mean switching this part that I attach at the top of the motor.... Then I have tried to switch it...

But how to Take the gear box apart?

Servo motors must not be powered from the 5v pin on the Arduino !

Use a 6v battery 4XAA batteries.

The battery negative must be connected to the Arduino GND.

There should be 4 screws you can remove to then expose the gear train.

The proplem is that I have the blue one... I think it is called sg90

So I can't open it to see what is the proplem with the gears

Then go with the lack of current from the board to make it work and move to having its own PSU.

Some of the super cheap servos are glued together and many use the same type number even though they are often just cheap CLONES and not the original MG90 series.
These often work just fine for most people once they sort out the power requirements.

Iam sorry but I don't understand you.... Do you mean giving it an external power supply... If so I think your are wrong because the proplem isn't in the power.. Bec it sometimes work and sometimes make sound like ziiii so what I think is its proplem in the gears of the motor.. But I can't open the motor

If you're right and the problem is with the servo gears and you can't get to the servo gears then your solution is simple. Buy another servo. SG90s cost almost nothing. In fact buy 2 or 3 in case you get another one that is dead on arrival as cheap clones sometimes are.

Since you don't even want to try the advice you're given then there is nothing else left.


In my country it is not cheap.. Or it is not cheap for me... I want to try the advice why not... But I suggset begining with the more accurate one.. But my proplem is that I can't open the servo motor. 1637498971888698843908404979003|375x500

You can try to open it but there is a chance of breakage due to it being a sealed unit.
If it sometimes works there is still a strong chance that the power from the board is insufficient.

Adding its own PSU would be my First choice.
Breaking it open would be my second choice.

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OK now I agree to what you are saying.

This is my circuit so what to do with the power supply for the servo and what to do with the power suplly of the arduino and ultrasonic sensor...

Connect the positive servo wire to the battery +6v lead.

Connect the negative servo wire to the battery negative lead then to Arduino GND.

The way you power the Arduino in your schematic is fine.

They need a COMMON GROUND so both the board and the arduino need to share that.
But the servo needs its own PSU which should have enough amps (current) to run the servo.

Typically the voltage should be 5 volts but the amperage should be at least 250 mA preferably more.