Why does one wheel does not turn?

Its plug is not fully in, or its wire got caught and snapped. Push that motor's plug fully into its port. Follow the wire from motor to board. Look for a cut or pinch near the wheel. Tie loose wires to the frame so the wheels cannot catch them (step 20).

Updated 2026-10-27

SunFounder GalaxyRVR: one wheel does not turn

Researched by Riley Hart · based on SunFounder GalaxyRVR build guide and docs · we may earn a commission

Short answer

Its plug is not fully in, or its wire got caught and snapped. Start with this: Push that motor's plug fully into its port.

Why it happens

Its plug is not fully in, or its wire got caught and snapped.

How to fix it

Push that motor's plug fully into its port.
Follow the wire from motor to board. Look for a cut or pinch near the wheel.
Tie loose wires to the frame so the wheels cannot catch them (step 20).

Check the step it comes from

Step 20 of 49

Tie the motor wires

Use the cable ties to hold the motor wires against the frame, away from the wheels.

Tip: Loose wires get caught in the wheels and snap. Reviewers hit exactly this.

Check: No wire can touch a wheel.

Common mistake: Pulling ties so tight they pinch the wire. Snug is enough.

See this step in the full build guide

Still stuck?

Show the AI coach a photo

Open step 20 in the free build tool, tap Stuck and take a photo. The coach checks it against that exact step and tells you what to change. 3 free questions per kit.

Open step 20 →

Other GalaxyRVR problems

No camera picture in the appThe ESP32 CAM is in its adapter the wrong way, its ribbon is loose, or the camera is not getting power.The GalaxyRVR Wi-Fi does not show upThe rover is in upload mode, the battery is flat, or the camera board is not powered. The camera board makes the Wi-Fi.The app keeps disconnectingYour phone leaves the rover's Wi-Fi because it has no internet, or another network on the same channel interferes.The app sees the Wi-Fi but will not connectCustom code uploaded to the board replaced the rover's own program, or the camera board firmware is old.A wheel spins the wrong wayTwo motor plugs are swapped.No lights when charging or switching onThe battery plug is loose or the battery is flat.

All 12 GalaxyRVR problems and fixes · The full build guide

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Sources

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