An electronic system is described for controlling vehicle message lighting including turn and stop indicator signal lights, which system does not require any pre-existing wiring harness in either a towing vehicle 101 or any towed vehicle 104 to be in serviceable condition. In one embodiment the system implements a reliable wireless detection method based on feedback to confirm the state of operation of any such pre-existing “vehicle indication signal drive line” and includes a control apparatus that wirelessly transmits 230 instructions to at least one local receiver 150 controlling a number of message devices, including, but not limited to, vehicle indication signal lights. Another embodiment of the system bypasses any pre-existing wiring harness and permits the operator to manually over ride its detector. Advantageously, the portable control transmitter apparatus and each receiver apparatus 150 of the invented system are easily installed by a nontechnical person requiring minimal tooling and then operated by an unskilled user.