Testing The Charging System Using The Voltage Drop Test The first step in this process is to have the engine idling with the headlights on and the heater blower fan running at high output to put a ...

Ensure the circuit or device under test is powered off. Apply the probes across the diode (making sure to ensure proper polarity), then record the diode drop voltage.

To test the ground side voltage drop, place the VOM’s positive probe on the case of the alternator and the negative probe on the negative (-) battery post. If the reading is above 0.50 volt ...

A technician with a voltmeter will perform a “voltage-drop” test to determine the cause of your car’s intermittent no-start problem. If you cannot get the car to a garage, look for dirty or ...