A new feature spotted inside Tesla’s mobile app could make trailer light checks a one-person job. Strings found in version 4.55.7 of the Tesla app point to an upcoming “Trailer Light Test” that owners can trigger remotely from their phone, without needing to walk back and forth to the cab or ask someone to sit in the driver’s seat.
A developer found the feature by looking at the code of app version 4.55.7. The code contains text that says “Trailer Light Test to easily verify that your trailer is properly connected”. Tesla has not put this in their official notes yet it is clear they are preparing the app for it.
Operation of the light test
The system will likely work by plugging the trailer into the factory connector first. Then the owner opens the app and picks the vehicle control menu. A person can start a programmed list of light checks by tapping the phone.
The car will turn on the running lights and the brakes and the turn signals in a row. And the driver can stay at the hitch to see if every lamp is working. This is like the “Trailer Light Test” that the Cybertruck already has on its main screen.
Compatible vehicle models
Cars with a factory tow package are the most likely to get this update. This includes the Model Y and the Model X and the Cybertruck. And some Model 3 cars with the right gear may get it too. The vehicle has to be online for the app to talk to it. So it works just like the remote horn or door locks do.
Drivers must check their trailer lights to stay safe and follow the law. But doing this alone is hard without a second person. Other brands like Ford and Chevy have a “Trailer Light Check” in their apps for truck owners. And Tesla adding this tool brings their tech closer to what other trucks offer.
Tesla has not given a date for when everyone can use this. Features often appear in the app code before they are ready for the public. So it might take some time for the final software update to arrive. And the company has not listed the feature on its support pages yet.
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