Multimeter Voltage Testing for TV Repair - Where to Place the Test Leads - Ground and Positive

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Multimeter Voltage Test Help
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Troubleshooting a TV problem will often require the use of a multimeter, to check voltages.  Once of the most common questions that we receive on our videos that involve a multimeter, is where are we supposed to place the ground lead on the multimeter. We alwaus face the positive test lead on the pin that we are reading the voltage of.  
Power supply boards are made up of a hot and cold side.  You can see the hot side,  that is defined as in this our live area and the remaining parts of the board is the cold outside.  
Depending on which side of the board, either the hot or cold you are testing voltages on, the placement of the ground lead will differ.  When testing a voltage on the hot side, put the positive test lead on the pin you are testing, and then put the ground lead on the negative side or on the heat sink on the Hot side.  
We are showing this example, while testing this capacitor, with the ground lead on the negative side of the cap, and then ground lead on the negative side.
Both show the same result.
If the heat sink on your power supply is painted, like the heat sink on the screen, then it will not show an accurate measurement if you place the ground lead on the painted part.  
Look to put the ground lead on the unpainted portion to get an accurate measurement.  
When testing the cold side, the ground negative lead should be placed on the metal part of the chassis to serve as the ground for the voltage testing.  
It can be placed in a metal screw hole that was holding the back cover on the TV, or in one of the metal holes on the chassis.  
Having the ground lead making contact with the metal part of the chassis, is the most important.
If there is no metal chassis and the boards are mounted to plastic, then you will need to use the ground points on the boards.
Here, we are showing the multimeter in action testing the voltage on the power supply.  We have the test lead on the test pin and the ground pin on the metal part of the chassis.

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