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[Robot kits](https://robotsforthat.com/robot-kits/) / [ELEGOO Smart Robot Car V4 troubleshooting](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-troubleshooting/) / **The app will not connect**

Updated 2026-10-27

# ELEGOO Smart Robot Car V4: the app will not connect

Researched by [Riley Hart](https://robotsforthat.com/author/riley-hart/) · based on ELEGOO Smart Robot Car V4 build guide and docs · we may earn a commission

Short answer The board switch is on upload, or the phone left the car's Wi-Fi. Start with this: Slide the small switch on the expansion board to cam.

## Why it happens

The board switch is on upload, or the phone left the car's Wi-Fi.

## How to fix it

- Slide the small switch on the expansion board to cam.
- Join the ELEGOO Wi-Fi again and stay connected when it says No internet.
- In the app, tap the link icon in the top right.

## Check the step it comes from

Step 26 of 29

### Switch to camera mode

On the expansion board, slide the small switch from upload to cam.

**Check:** Switch is on cam.

**Common mistake:** Leaving it on upload. The app cannot connect.

[See this step in the full build guide](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-build-guide/#step-26)

Still stuck?

## Show the AI coach a photo

Open step 26 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 26 →](https://robotsforthat.com/lab/build/elegoo-car-v4/steps/#step-26)

## Other ELEGOO V4 problems

[No camera picture The camera cable is loose or the camera board is upside down.](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-troubleshooting/#no-video)[The car spins in circles or drives backward Motor plugs are in the wrong ports.](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-troubleshooting/#spins)[The remote does nothing The plastic tab is still in the remote, or the battery is low.](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-troubleshooting/#remote)[It misses the line The line sensor needs contrast and the right threshold.](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-troubleshooting/#line)[Nothing turns on The battery is flat or switched off.](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-troubleshooting/#no-power)[A wheel wobbles or falls off The wheel went on at an angle or the screw is missing.](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-troubleshooting/#wheel-wobble)

[All 8 ELEGOO V4 problems and fixes](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-troubleshooting/) · [The full build guide](https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-build-guide/)

**ELEGOO Smart Robot Car Kit V4.0** About $66 to $80. Every part and tool in one box.

[Check price on Amazon](https://www.amazon.com/dp/B07KPZ8RSZ?tag=robotsforthat-20)

## Sources

- [ELEGOO Smart Robot Car V4.0 assembly tutorial (PDF)](https://drive.google.com/drive/folders/1hACczXN-CzxTFHsO3yrLW7QJ1HhHiZJJ)
- [ELEGOO Smart Robot Car V4.0 downloads](https://www.elegoo.com/blogs/arduino-projects/elegoo-smart-robot-car-kit-v4-0-tutorial)

Drawings by robotsforthat. ELEGOO Smart Robot Car V4 is a trademark of ELEGOO. We are not affiliated with ELEGOO.

HTML version: https://robotsforthat.com/robot-kits/elegoo-smart-robot-car-v4-app-wont-connect/