No Power at all!

I have the above device (Sanyo dp50747 Plasma TV), and it looks exactly like the one posted in the step by step guide found here (Repairing Sanyo dp50747 Plasma TV Fuse - Power Board) . I've checked the capacitors for leaks and blows to no avail. So I think it is either a blown fuse or Power Board. I have found a multimeter to check the voltages but do not have the instruction booklet for it and can't find one to download and I've never really used one. So my question is what voltage to I set my multimeter to? The settings I have on it are

DCV 500v, 200v, 20v, 2v;

OHM 200, 2k, 20k, 200k, 2m;

DCA 2mA, 20mA, 200mA;

ACV 200v, 500v

and what looks to be a arrow pointing to the middle of a plus sign.

Any help I can get would be greatly appreciated!

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Mikkhail, to check the capacitors, you need an impedance meter. A regular multimeter will not do. It may or may not show continuity. To determine which voltage to set your multimeter. This depends on where you take the measurement. If the symbol you refer to looks somewhat like this -->|-- that is the symbol for a Diode. It should be in the instructions for your meter on how to use it to test diodes. Now for your TV, I suggest you first check the Fuse F601 and replace it with a 250V 10A fuse as needed. Step 3 of the guide you listed above shows the location of the fuse on your board. Use your multimeter to check for power. Caution, here you are still dealing with 110V AC so be careful, otherwise you might have a hair raising experience. Then check the Power Failure Circuit

This unit is equipped with a Power Failure Detector function included in the CPU which checks for an abnormal condition in the chassis power supplies.

If, while the power is on, a failure is caused by any of the following that results in a low voltage supply, the CPU will turn the unit off in 1.5 seconds to prevent further damage.

- Failure within the power supply circuits

- A short circuit in the load side from the supply.

1. Power Failure 1. Detected voltage failure for analog and digital circuits (Connected on IC801 pin 32.)

2 Power Failure 2. Not used on this model

Check the following if the unit is turned off by the power failure detector.

1. Disconnected the AC power cord for at least 10sec

2. Connect a DC voltmeter to the circuits shown in the attached image

3. Press the Power key and check for the proper voltage supplies.

4. If any of these voltages is low, the power failure detector should turn the unit off within 3 sec

I also attached the block diagram of the power lines. This may help you to properly measure the voltages. Those are DC voltages. Hope this helps to get you started.

Block Image

Block Image

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Comments:

Thank you oldturkey03 for the insight. My fuse F181 was bad. I've ordered a 5 pack of them in case there is something blowing that fuse so I can research further in case of another failure.

by evanrevans

@evanrevans, you are welcome

by oldturkey03

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Mikkhail will be eternally grateful.

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