# Picar-X motor problem

**URL:** <https://forum.sunfounder.com/t/picar-x-motor-problem/5019>\
**Category:** Robotic kit for Raspberry Pi\
**Created:** [September 29, 2026, 2:09pm UTC](https://forum.sunfounder.com/t/picar-x-motor-problem/5019 "2026-09-29T14:09:26Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Cootje001](https://avatars.discourse-cdn.com/v4/letter/c/77aa72/32.png) [@Cootje001](https://forum.sunfounder.com/u/Cootje001)\
**Post date:** [September 29, 2026, 2:09pm UTC](https://forum.sunfounder.com/t/picar-x-motor-problem/5019/1 "2026-09-29T14:09:26Z")

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When I’m testing the motors the wheels turn forward, but when I’m turning the motors backward, only one wheel is turning backward. The other one is still going forward. What can be the problem? I’m thinking something in the code, because (1,1) is forward and backward changes into (-1,1).

I’m using the testcode for servo’s en dc motors for this.

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**Author:** ![SunFounder\_Moderator](https://avatars.discourse-cdn.com/v4/letter/s/34f0e0/32.png) [@SunFounder\_Moderator](https://forum.sunfounder.com/u/SunFounder_Moderator)\
**Post date:** [September 30, 2026, 7:59am UTC](https://forum.sunfounder.com/t/picar-x-motor-problem/5019/2 "2026-09-30T07:59:36Z")

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Are you running this calibration example?

> **[1. Calibrating the PiCar-X — SunFounder PiCar-X Kit documentation](https://docs.sunfounder.com/projects/picar-x-v20/en/latest/python/python_calibrate.html)**

If so, please press the number key 4 or 5 to switch between selecting the left motor and the right motor. During the test both motors will move, but only one of them can be selected at a time to change its direction. So please press 4 or 5 first to select the motor you want to calibrate, and then adjust its direction.

If you are running a different example, could you please send us a short video so we can see what is happening?Please upload them to Google Drive (or another cloud drive), share the link with us, and set the link permission to “Anyone with the link can view” so we can review them.

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**Author:** ![Cootje001](https://avatars.discourse-cdn.com/v4/letter/c/77aa72/32.png) [@Cootje001](https://forum.sunfounder.com/u/Cootje001)\
**Post date:** [September 30, 2026, 4:30pm UTC](https://forum.sunfounder.com/t/picar-x-motor-problem/5019/3 "2026-09-30T16:30:19Z")

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Ok, now I understand. I can only change direction of one motor at the time. Working for me now. Thanks.