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Circuit Malfunctions

There are three electrical conditions that can cause a non-working circuit: an "Open Circuit," a "Short Circuit" or a "Grounded Circuit." These conditions can also be caused by intermittent or poor connections.

Open Circuit:




Open Circuit
An open circuit occurs whenever there is a break in the circuit. The break can be corrosion at the connector, a wire broken off in a component, a wire that burned open from too much current or a component not operating as it should.

Short Circuit:




Short Circuit
A short circuit happens when the current bypasses part of the normal circuit. This bypassing is usually caused by wires touching, salt water in or on a component such as a switch or a connector, or solder melting and bridging conductors in a component.

Grounded Circuit:




Grounded Circuit
A grounded circuit is like a short circuit but the current flows directly into a ground circuit that is not part of the original circuit. This may be caused by a wire rubbing against the frame or body. Sometimes a wire will break and fall against metal that is connected electrically to the ground side of the voltage supply. A grounded circuit may also be caused by deposits of oil, dirt, or moisture around connections or terminals, which provide a good path to ground.

Intermittents And Poor Connections
Most intermittents are usually caused by faulty electrical connections or wiring, although occasionally a sticking relay, solenoid, or loose ground point can be a problem.