Header Banner
WonderHowTo Logo
WonderHowTo
Car Mods
wonderhowto.mark.png
Gadget Hacks Next Reality Food Hacks Null Byte The Secret Yumiverse Invisiverse Macgyverisms Mind Hacks Mad Science Lock Picking Driverless
Home
Car Mods

Keep Cars Off Your Bumper with This Arduino-Controlled Rear Window LED Marquee

Sign displaying "OFF" in red LED lights.

There are plenty of times when it would be nice to be able to give other drivers a piece of your mind, or let them know you're having car trouble so they go around instead of riding your bumper.

While there are several gestures that can certainly get the point across, none of them are quite as effective as this rear-window LED marquee.

Robert Dunn of DunnRight Software used an Arduino ADK connected to a trailer light hookup using optocouplers as seen in the circuit diagram below. It receives input from the turn signals and lights and only turns on when the lights are in use because it doesn't have very high visibility during the day.

Robert hand soldered a matrix of 480 LEDs, making the grid sparse so that he could still see through the rear window.

Using the ADK, he can send messages to the cars behind him, and during normal driving, the marquee advertises his personal website's URL.

Check out the videos to see demos of the turn signals and custom messages.

You can find more photos of the setup in the album on Google+, and more details about the build plus all the code over on Ryan's blog.

Apple's iOS 26 and iPadOS 26 updates are packed with new features, and you can try them before almost everyone else. First, check Gadget Hacks' list of supported iPhone and iPad models, then follow the step-by-step guide to install the iOS/iPadOS 26 beta — no paid developer account required.

Related Articles

Comments

No Comments Exist

Be the first, drop a comment!