less then at full brightness when neither the brake light bulb 50 nor the tail light bulb 52 are burned out the warning led 76 will not be illuminated at all referring finally to fig9 an exemplary schematic of the right turn signal driver circuit 82 is illustrated together with the right rear turn signal bulb 66 the buffer 86 and the buffer 88 the doubled voltage is supplied from the voltage doubler 80 to a first side of a resistor 168 a second side of which is connected to the collector of a transistor 170 and to the gate of a mosfet 172 the drain of the mosfet 172 is connected to v and the source is connected to the non grounded side of the right rear turn signal bulb 66 a first side of a resistor 174 is connected to the right turn signal output of the turn signal switch 40 and a second side of the resistor 174 is connected to the anode of a diode 176 and the anode of a diode 178 the cathode of the diode 176 is connected to the input of a schmitt hex inverter 180 a first side of a capacitor 182 and a first side of a resistor 184 a second side of the capacitor 182 and a second side of the transistor 164 are connected to ground the output of.