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Troubleshooting Tools

TROUBLESHOOTING TOOLS:

Isolating the problem (Step 3 of TROUBLESHOOTING PROCEDURES) requires the use of a voltmeter and/or ohmmeter. A voltmeter measures voltage at selected points in a circuit. An ohmmeter measures a circuit's resistance to current flow. It has an internal battery that provides current to the circuit under test. Disconnect the car battery when using an ohmmeter because the battery voltage will cause the ohmmeter to give false readings. Also. do not use an ohmmeter on solid-state components. The voltage that the ohmmeter applies to the circuit could damage these components.
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