When the indicator is turned on current flows through the power supply heater coil, through the made contacts, and lights the indicator lamps on the vehicle - at the same time, as warming up the bimetallic strip which bends when heated and opens the Circuit diagram switch contacts, turning off the lights and the heater coil.

Canceling the power supply Signal After completing your turn or lane change, be sure to turn off your indicator. Most cars will automatically turn off the signal after the turn is completed, but if it doesn't, simply push the lever in the opposite direction to deactivate it.

Off Indicator, An illuminated off indication means the Projec system associated signal is showing a proceed aspect. These are mainly used at stations, for the benefit of the train crew and platform staff. When the display is blank, it means that the associated signal is in danger.

In most cars, the turn signal lever is located to the left of the steering wheel. Shifting the current lever up indicates a right turn and shifting it down indicates a left turn. Your turn signal should turn off after a turn or a lane change, but if it does not, you should turn it off and on manually, as soon as possible.

You will often see circuit diagrams carrying less than 20 amps switched directly, while circuits of 30-40 amps can sometimes be directly switched but will often be controlled by relays. Anything above 40 amps is pretty much always off and on a relay.