2021 Ford F-150 Trailer Light Check Instructions

New for 2021, select Ford F-150 trucks will come equipped with a Trailer Light Check feature that lets you check your trailer light operation all from your smartphone. This step-by-step guide covers how to check your trailer lights using the new F-150 Trailer Light Check function on your FordPass™ App.

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Turn on the vehicle ignition and make sure the transmission is in park.
Open the FordPass™ app and login with your username and password.
Tap Vehicle, then tap Trailer Light Check.
Go to the back of the trailer and press Start.

The vehicle and trailer lights will cycle in sequence:

Left turn signal
Right turn signal
Brake lights
Reverse lights (if equipped)

How to Check Your Trailer Lights Manually from in the Truck

Checking your trailer lights on the 2021 Ford F-150 is easier than ever, thanks to the truck’s built-in Trailer Light Check feature. Designed for convenience and safety, this system helps you confirm that all your trailer lights—brake, turn, tail, and reverse—are working properly before hitting the road. Here’s how to do it:

Start with setup: Make sure your trailer is properly connected to your F-150 using the factory trailer wiring harness. Turn the ignition to the “On” position without starting the engine.
Access the menu: On the instrument cluster screen, navigate to “Towing” using the steering wheel controls, then select “Trailer Light Check.”
Select your trailer: If you’ve saved a trailer profile, choose it. Otherwise, select “Add Trailer” to set one up.
Begin the test: The system will automatically cycle through each trailer light—running, left turn, right turn, and brake lights—displaying progress on-screen.
Walk around your trailer: As the lights flash, check that each one is working correctly. The test repeats until you cancel it.

This smart feature takes the hassle out of solo trailer checks, helping ensure your F-150 and trailer are fully road-ready and visible wherever your haul takes you.