Testing For Voltage

Voltage Check:

1. Connect one lead of a test light to a known good ground. If you are using a voltmeter, be sure it is the voltmeter's negative lead that you have connected to ground.
2. Connect the other lead of the test lamp or voltmeter to a selected test point (connector or terminal).
3. If the test lamp glows, there is voltage present. If you are using a voltmeter, note the voltage reading. It should be within one volt of measured battery voltage. A loss of more than one volt indicates a problem.

Continuity:

4. A quick test of wire continuity can often be made using voltages of solid state modules.

If the continuity of the wire is good, 5 volts will be found at the switch connector. This test can be performed only with a Digital Voltmeter. Analog meters or Test Lamps will not work.

Voltage Test:

The test shown illustrates the same point with another type of input.

If the continuity of the wire is good, battery voltage will be found between the connector and a source of battery voltage. Again use only a Digital Voltmeter for this test.