After adding a 4-way switch to an existing circuit, I have become know around work as someone who can troubleshoot electrical problems. However, a coworker came to me with a question, and I'm not sure if there's an easier way to troubleshoot his problem than my method. He has a light circuit with two 3-way switches and one 4-way switch. He says the lights don't work in certain switch positions. I had said that he needs to use a voltmeter and find the correct "hot wire" from one of the 3-way switches and trace everything through the 4-way switch to the other 3-way switch. Is there an easier way to do this? Thanks. Dave

Hi folks, A quick question? My electrical panel started making a buzzing noise. I tried to identify if it was a breaker by turning them off in sequence but to no avail. So I turned off the main breaker then turned it back on and the buzzing stopped. It seemed to start after I plugged the block heater in my truck in, which may have had some condensation in the cord receptical. Does anybody have any idea what the cause might be? Any help or ideas would be appreciated. BTW I uplugged the block heater and the buzzing hasn't come back. Thanks in advance F.O.G.:confused: