Turn Signals: Description and Operation

1. When operation is normal
^ When the ignition switch is switched to the "ON" position, battery voltage is applied (via the hazard switch) to the turn-signal and hazard flasher unit.

^ When the turn-signal switch is switched to the LH" (or "RH") position, Tr1 (within the flasher unit) is switched ON and the relay contact (also within the flasher unit) is switched ON. As a result, the "LH" (or "RH") turn-signal lights and turn-signal indicator light illuminate.

^ At the same time, charging to the capacitor (via R2) begins, and charging continues until the lower-limit potential (set by COM3) is reached.

^ When the capacitor becomes fully charged, the COM3 output reverses and Tr1 is switched OFF; the relay contact is also switched OFF, and, as a result, the "LH" (or "RH") turn-signal lights and turn-signal indicator light are switched OFF.

^ At the same time that Tr1 is switched OFF, the capacitor begins discharging, and, when discharging finishes, the output of COM3 once again reverses and Tr1 is switched ON, after which the "LH" (or "RH") turn-signal lights and turn-signal indicator light illuminate.

^ As a result of the continued repetition of the steps described above, the "LH" (or "RH") turn-signal lights and turn-signal indicator light flash ON and OFF repeatedly.

2. If one light's wiring is damaged or disconnected
^ If the bulb for one turn-signal light is damaged or disconnected, the result is an overall increase of the resistance for the entire light circuitry, resulting is a decrease of the voltage at the R1 part within the flasher unit.

^ As a result of this being detected, the lower-limit potential set by COM3 is increased, with the result that the time required for charging of the capacitor becomes shorter.

^ As a result, the ON and OFF cycles of Tr1 also become shorter, and thus the number of flashes of the lights becomes greater.