How To Identify An Open Circuit
- With voltmeter:
An open circuit is determined by measuring the voltage between respective connectors and ground using a voltmeter, starting with the connector closest to the power supply. The power supply must be turned ON so that current flows in the circuit. If voltage is not present between a particular connector and ground, the circuit between that connector and the previously checked point is open.
- With ohmmeter:
Disconnect all connectors affected, and check continuity in the harness between adjacent connectors. When the ohmmeter indicates "infinite", the harness is open.