An electronic control circuit controls a vehicle's lamp to selectively operate as a turning signal, emergency signal, or vehicle running lamp. Notably, the circuit permits the lamp to operate as an emergency signal lamp even when the vehicle is off. The circuit includes a supply circuit, a control circuit, and a disrupt circuit. The supply circuit supplies voltage to the lamp if either or both of a vehicle running signal and a flash signal have a first input value. Meanwhile, the control circuit generates a control signal having a first control value if the vehicle running signal and the flash signal have different values, and a second control value if the signals have the same value. The disrupt circuit then connects the lamp to ground if the control signal has the first control value, but disrupts that connection if the control signal has the second control value.