Pesto's first drive = electric mystry

[spider2081]

A device that draws 2 Amps at 13.2 Volts is a 26.4 Watt device. Watts divided by Volts = Amps so the higher the Voltage the lower the Amperage drawn. A 26.4 Watt device at 14.5 Volts is going to draw 1.82069 Amps

Yes this is a valid form of the power equation I+P/E However using the equation to calculate the power and re-using that power to calculate the current from a different applied voltage might be flawed.
I have taken a number of lamp bulbs used on the Fiat Spider systems and applied an increasing DC voltage from a variable power supply to the bulbs. For each bulb the current drawn and bulbs brightness increased as the voltage applied was increased. I started at 0 volts and stopped at 16 volts.
When looking at a light bulb chart most wattages are stated for a specific operating voltage. I'm thinking if the voltage is increased from that stated voltage the wattage would also increase.
I have found the same is true when testing the coolant fan motors, wiper motors and heater fan motors. As the voltage is increased the current increases and the speed of the motor increases.

[Jon124]

A device that draws 2 Amps at 13.2 Volts is a 26.4 Watt device. Watts divided by Volts = Amps so the higher the Voltage the lower the Amperage drawn. A 26.4 Watt device at 14.5 Volts is going to draw 1.82069 Amps

Yes this is a valid form of the power equation I+P/E However using the equation to calculate the power and re-using that power to calculate the current from a different applied voltage might be flawed.
I have taken a number of lamp bulbs used on the Fiat Spider systems and applied an increasing DC voltage from a variable power supply to the bulbs. For each bulb the current drawn and bulbs brightness increased as the voltage applied was increased. I started at 0 volts and stopped at 16 volts.
When looking at a light bulb chart most wattages are stated for a specific operating voltage. I'm thinking if the voltage is increased from that stated voltage the wattage would also increase.
I have found the same is true when testing the coolant fan motors, wiper motors and heater fan motors. As the voltage is increased the current increases and the speed of the motor increases.

Your findings are correct. Passive devices like bulbs and motors are basically just an impedance in the electrical circuit. The resistance value is fairly constant when powered although it does change with temperature. Since resistance is constant using ohms law gives you increasing current with increasing voltage. Actively regulated devices such as a radio are capable of outputting a fixed power, with some tolerance on the input voltage. For active devices as supply voltage increases current draw decreases because the power is held constant.

[TX82FIAT]

Hint, if you are going to take the cowl off to lube and potentially refurbish the wiper motor and linkage. Put some painters tape of masking tape on the edges of your fenders where the cowl will slide forward. Its real easy to scratch the paint removing the cowl if not careful. However, it is even easier to scratch putting it back in. While you are in there you may want to inspect the condition of the general area and consider cleaning, scraping and painting is any rust found.

[70spider]

Update: bleed the brakes and have a decent peddle so I took him out for a drive to the filling station. Everything went well, ran with the headlights on and used the turn signals and the fuse didn't go out. Also, I cleaned the connectors a bit better to the alternator, plus put a ground on it and it worked fine with no charge light coming on. So, electrical seems good for now. Thanks everyone on the input, it made me realize that I need to study automotive electrics.