BILTIT hits the nail on the head. Lowering voltage will reduce amp draw. Exception is SOME motors will increase current because of the reduced cemf. I have tested fuel pumps to prove that current will always decrease with lower voltage. The pumps tested dropped amperage as voltage decreased. There was only a slight rebound in amp draw when voltage got down to 4 volts. The pump was hardly spinning, and the amp increase was minimal. Most factory fan set ups have dual or variable speeds. Let's use a GM or Ford for example with a simple 2 speed fan. How do they achieve the lower fan speed? They use a RESISTOR to reduce voltage supplied to the fan. Lower voltage, lower amperage. High fan speed is high (full) voltage, high amperage. If lower voltage results in higher current draw in an automotive circuit, please give me an example different than the following: (Low battery voltage can cause high starter amp draw due to reduced cemf AND increased mechanical resistance.)
Burned and melted connectors add resistance to a circuit resulting in REDUCED amp draw. The energy emitted from a bad connection is heat. This voltage drop is stealing voltage from the rest of the circuit. Reduced voltage, reduced amperage. A good thing to remember about DC electrical motors is: mechanical resistance will INCREASE amp draw and, electrical resistance will DECREASE amp draw.
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