Adding Turn Signals to Trailer Side

The project aims to create side signals for trailers which can also be used as clearance light and will function on electric brakes and a brake controller.

An Attiny24 microcontroller on a prototyped board is used to run the code. Although it taps into those signals for logic, an in-line harness was built for testing that passes the signals from the 6-pin connector to the trailer. For testing, two standard LED clearance lamps attached as left and right turn signals are used by the device. In the event of failure, nothing is compromised since this system is an add-on to the existing trailer wiring. These trailer signals do not require tampering with the inner structure of the vehicle.

There is no shortage of patents for adding this type of capability although they usually require a unique transmitter aboard the truck that communicates with another unique receiver on the trailer. Any standard clearance light can be used and will function as a clearance light when the lights are ON. New lights can be added or the wiring to the existing clearance lights can be intercepted, by needing the electric brakes and brake controller.

Rest of the project