Indicators are amber lights located on the extreme corners of the vehicle. A column mounted switch, operated by the driver, directs a pulsing current to the indicator lights on one side of the vehicle or the other. These pulsing lights warn other road users of the vehicles intended change of direction.
Once activated they continue until the switch is cancelled either by the operator or by a cancelling mechanism in the switch. The cancelling mechanism operates after a turn has been completed and the steering wheel is returned to the straight ahead position.
The circuit consists of:
If the indicator switch is turned to indicate a right-hand turn, current from the battery flows through the fusible link to the ignition switch, where it is directed through a fuse to the flasher unit.
The flasher unit uses a timing circuit to pulse the current flowing out of the flasher unit 60 to 120 times per minute. This pulsing current is directed through the indicator switch to the right-hand indicator lights at the front and rear of the vehicle, causing the lamps to flash on and off. A pilot light on the instrument cluster also pulsates. The operation of the flasher unit also produces a clicking sound to warn the driver that the indicators are in operation.
When the indicator switch is returned to the “off” or central position, no current flows through the flasher unit so the timer circuit is switched off.
When the indicator switch is turned in the opposite direction, it directs the pulsing current to the left-hand lights at the front and rear of the vehicle as well as the left hand pilot light on the instrument cluster.
Most vehicles are equipped with hazard warning lights. This circuit is similar to the indicator lights except that it simultaneously causes a pulsing in all exterior indicator lights and both pilot lights on the instrument panel .
These can warn other road users that a hazardous condition exists, or that the vehicle is standing or parked in a dangerous position on the side of the road.
