A customer recently called to ask questions about the electrical system on his machine. I asked if he had a voltmeter. There was a long pause, then he said, “Yes, but I don’t know how to use it.” He ...

If you’ve never used a voltmeter to test electrical circuits on 12-volt farm equipment, cars or trucks, but wanted to learn, here’s how: Voltmeters cost from $15 to $300. $50 will buy an economy-grade ...

Disconnecting the battery while the engine is running isn't a valid test for alternator function and may damage sensitive electronic parts. Instead, use a common voltmeter and the following test ...