Electrical System Open Circuit Diagnosis

OPEN CIRCUIT TEST
On all electrical circuits, continuity must exist from the source of power battery positive voltage (+) to the unit where the power is used and back up to the source of power battery ground (-) terminal.
^ A check at each connection in a circuit, starting at the battery, will locate an open circuit or will show that the circuit is complete.
^ An ohmmeter or self-powered test lamp connected at any two points of a circuit, with the power removed from the circuit, will show if the circuit between the two connections is open or continuous.
a. If the meter does not move or has a slight movement (high resistance), the circuit may have a poor connection or broken wire.
b. If the bulb lights, the circuit is continuous.
c. If the ohmmeter movement is great or full (low resistance), the circuit is complete. If the bulb lights, the circuit is complete.