i assume that the system is wired so that the original wire for the light is used to power the xenon?
if so, you need to add a resistor in parallel with the current system, to lower the resistance to the 'right' level.
Power = Volts x Amps
old power = 55 = 12 x amps => 55/12 = 4.58 amps
new power = 35 watts = 12 x amps => 35/12 = 2.92 amps
so you need to loose 4.58 - 2.92 amps = 1.66 amps
1.66 x 12 = (roughly) 20 watts 12/1.66 = resistance = 7 ohms
so - you need a 7 ohm, 20 watt resistor (BIG!!!!) - or a 20 watt bulb across the power to bulb to ground connection.
IF the power to bulb is used just to power the 'black box' and the main power is taken from the battery, then you need to stick a bulb in between there and ground - try a 20 watt to start withj (im not sure quite how smart the syetm is)...
C140 420 CL
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