K 1500 Truck 4WD V6-262 4.3L VIN Z (1993)
Turn Signal Lamp: Description and Operation
With the Ignition Switch in RUN or START, voltage is supplied through the TURN-B/U Fuse and Turn Flasher to the normally closed contact of the
Hazard Flasher Switch in the Turn Signal Switch Assembly.
With the Signal Switch in LH Turn position, voltage is supplied to both the LH Turn Indicator and the LH Front Park/Turn Lamp (LT BLU [14]
wires). Voltage is supplied to the LH Rear Turn Lamp (YEL [18] wire).
The Lamps go on immediately. They begin to flash when the current flow heats up the timing element in the flasher and it repeatedly opens and closes
the circuit.
The voltage supplied to the LH Front Park/Turn Lamp will also be supplied to the LH Front Marker Lamp. If the Light Switch is in the OFF position,
the LH Front Marker Lamp will find a path to ground through splice S105 and the many Lamps connected in parallel to ground. These Lamps provide
low resistance paths to ground. The Marker Lamp will flash with the Turn Lamps. The Lamps used for the ground path will not flash, however, since the
voltage drop across the Marker Lamp is much higher than that across the other Lamps.
When the Light Switch is in either PARK or HEAD, voltage is supplied through the PARK LP Fuse, Lamp Switch, and splice S105 to the Marker and
Park Lamps. If the Turn Signal Switch Assembly is in TURN LEFT, the LH Front Marker Lamp will have voltage at both connections and will go out.
When the flasher removes voltage to the Turn Lamp, the Marker Lamp will be grounded through the Turn Lamp and will go on. In this way, the LH
Front Marker Lamp will flash on when the LH Front Park/Turn Lamp goes off, and off when the Turn Lamp goes on.
With the Turn Signal Switch Assembly in TURN RIGHT, voltage will be supplied to the RH Lamps in the same way.
