90 Quattro 20V L5-2309cc 2.3L DOHC (7A) (1990)
Low voltage: A low voltage reading across the two switch contacts indicates almost no difference in potential. Resistance across the switch is
low-most of the battery voltage is passing through the switch and is still available to power the lights.
High voltage: Any significant voltage reading indicates a difference in potential across the switch contacts. Excessive resistance is loading the
circuit, causing a voltage drop-voltage is consumed overcoming the resistance of the switch, and less is left to power the lights.
Maximum allowable voltage drops recommended by the Society of Automotive Engineers are:
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0.0 volt for small wire connections
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0.1 volt for high current connections (example: fuel pump, headlights)
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0.1 volt for ground connections
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0.2 volt for high-current cables (Example: battery/starter cable)
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0.3 volt for switch or relay contacts