Continuity And Resistance Check

Disconnect the battery terminal or wire so there is no voltage between the check points.
Contact the two leads of an ohmmeter to each of the check points.

Fig 1: Checking Switch Continuity
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the circuit has diodes, reverse the two leads and check again.

When contacting the negative lead to the diode positive side and the positive lead to the negative side, there should be continuity.

When contacting the two leads in reverse, there should be no continuity.

Fig 2: Checking Diode Continuity
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Use a volt/ohmmeter with high impedance (10k/V minimum) for troubleshooting of the electrical circuit.

Fig 3: Identifying Digital And Analog Type Volt/Ohmmeters
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002