Light up your Mercedes.
Thirty-plus headlight effects, played from your phone through the OBD port. Nothing permanent.
For a vehicle you own, parked and stationary, off public roads. For show and demonstration only.
Now playing · All Flash
Your headlights, on your terms.
MercLight talks to the front lighting modules the same way a workshop tool does: over ordinary diagnostic commands, through a Bluetooth OBD adapter you plug in yourself.
- Thirty-plus effects, one tap
- Police bursts, dual strobes, Knight Rider, meteor shower, heartbeat, SOS, each with a live preview on the tile so you know what you're about to play.
- Build combos and playlists
- Chain effects back-to-back, loop them, and save the sequence. Gapless mode keeps the ECU unlocked across the whole run so there's no pause between steps.
- Auto show on unlock
- Arm the keyfob monitor and walk away. When you unlock the car, your chosen effect plays. On Android it keeps watching with the screen off.
- Tuned to your car
- The app reads your VIN, identifies the lighting modules, and learns which segments work, so effects run faster and cleaner on your lamps.
- Demo mode, no car needed
- Try every screen against a demo vehicle before you ever plug in. It never touches a real car. There is simply no link for a command to travel down.
Plug in. Connect. Play.
Ignition on; the engine can stay off. That's the only preparation.
- 1
Plug in the adapter
Any ELM327-compatible Bluetooth LE adapter into the OBD-II port under the dash. KONNWEI and vLinker BLE are what we test with.
- 2
Tap Connect
The app finds the adapter, reads the VIN, identifies the lighting modules and unlocks the front ECU. About ten seconds.
- 3
Pick an effect
Tap a tile. The lamps play it and return to normal. Build a combo, save a playlist, or arm the show to play when you unlock.
Four tabs. Nothing to learn.
-
Control
Connect, see your car and its lights, and arm the automatic show. The headlight graphic mirrors what the real lamps are doing.
-
Effects
A grid of thirty-plus effects with live previews. Tap to play; tap + to add to a combo. Playlists save the sequences you like.
-
Vehicle
Identified from the VIN, decoded on the phone. Clear stored codes on the lighting modules with one tap if anything ever flags.
-
Settings
Theme, language (English, Arabic, German, Spanish, French), adapter type, demo mode, and your purchases, tied to your vehicle.
Unplug the adapter and the car is
exactly as it was.
No coding, no flashing, no modified firmware. Every command is temporary; the car returns to its normal state on its own, every time.
- No coding
- No flashing
- No modified firmware
Five effects, free on your own car.
No trial period and nothing to unlock first. Plug in the adapter and these run. Hover any light to see what it does.
- All Flash FreeBoth headlights flash together
- Police Burst FreeTwo flashes left, then two right
- Knight Rider FreeKITT-style sweeping eye
- Accent Sweep FreeAccent lights sweep across
- Breathing FreeA soft breathing pulse
The other 25 unlock with one purchase.
Buy once. Yours for that car.
No subscription. Purchases are handled by Apple or Google in your local currency.
Free
Free forever
- Five effects: All Flash, Police Burst, Accent Sweep, Knight Rider, Breathing
- Full vehicle identification
- Combos and playlists
- Demo mode
Pro
Price set by your app store at launch
- Every effect, for one vehicle
- Auto show on unlock
- Gapless combos
- Restore on any phone
Own more than one Mercedes? Pro covers one vehicle, and it binds to that car the first time an effect plays. Additional cars are a repeatable one-time purchase. Purchase terms
Recent Mercedes-Benz. Any BLE adapter.
The app confirms your exact lighting modules before it ever sends a command, and when we add a mapping for a new car, it downloads to your phone without an update.
Supported models
- A-Class
- C-Class
- E-Class
- S-Class
- CLA
- CLS
- GLC
- GLE
- GLS
- G-Class
Models from 2016 onward. Available actions depend on the lighting modules fitted to your car. The app tells you before you buy.
Operating non-standard lighting on a public road is illegal in most places. MercLight makes no permanent changes, but where and how you use it is your responsibility.
Straight answers.
Is this safe for my car?
It sends the same diagnostic commands a workshop tool uses and makes no permanent changes. Use it only on a vehicle you own, off public roads, for show and demonstration purposes.
Which OBD adapter should I use?
Two families are supported. ELM327-compatible Bluetooth LE adapters (KONNWEI, vLinker BLE) are recommended and auto-detected. Legacy FF01 BLE adapters also work. Very cheap clones can be too slow for the fastest strobe tempos. If "strobe" or "max" looks choppy, drop to "fast" or "normal".
How do I connect?
1. Switch the ignition on. The engine does not need to run, but the lighting modules only answer when the car is awake. 2. Plug the adapter into the OBD-II port. 3. Open MercLight, tap Connect, and pick your adapter. The app reads the VIN, decodes the model, and unlocks the front ECU automatically.
Will this set warning lights on the dash?
Some actions can briefly raise a transient code. Open Vehicle → Clear errors to reset stored codes on the lighting modules. There are no lasting effects.
What's the difference between an effect and a combo?
An effect is a single animation: a police burst, a KITT scanner. A combo is a sequence of effects you build on the Effects screen; they play back-to-back, optionally looping. Gapless mode keeps the ECU unlocked across the whole combo so there's no pause between steps.
Do I need to keep the app open?
Tapping an effect works on both platforms. For automatic show-on-unlock, Android keeps watching with the screen off using a foreground notification; on iPhone the monitor runs while the app is open on screen, since iOS has no background service for this.
My car isn't listed. Will it work?
The app identifies your lighting modules directly rather than guessing from the model name. If it doesn't recognise them, it asks our server for a newer mapping and downloads it on the spot. Five effects are free, so you can find out on your own car before buying.
What data does the app collect?
A random per-install device id and your car's VIN, sent to our own server to attach a purchase to your vehicle. No advertising, no analytics, no tracking, no account. You can delete everything from inside the app. Full details in the privacy policy.
Your car. Your show.
Launching on Android and iOS together. Free to install, five effects included. Get the release notification and be first on your car.
Email us and we'll tell you the day it ships.
- Android
- iOS
- Coming to both stores at the same time.