26SI Series Alternator – Wiring Harness (Open Circuit) – Test

Electrical problems are often caused by failed electrical wires that have either an open circuit or a short circuit.

If an electrical wire or a connection is broken, the flow of electrical current through the circuit is interrupted. This would be an open circuit. The following procedure explains the test for an open circuit.

Test for an open circuit.

  1. Turn the battery disconnect switch and the key start switch to the OFF position.
  1. Disconnect both ends of the wiring harness.
  1. Install a jumper (connecting wire) between two of the electrical wires at one end of the wiring harness.
  1. Use a multimeter in order to check for continuity across the same two electrical wires at the other end of the wiring harness.
  1. Turn the multimeter dial to the 200 ohm range and measure the electrical resistance.
  1. If there is continuity between the electrical wires, the multimeter will have a reading of less than 5 ohms. If there is no continuity, the electrical wire is faulty. The wiring harness must be repaired or replaced.