Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

same is true coming out of line filter supply to the lower big supply .

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

same is true coming from line filter supply to the lower power supply same readings.

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

weird ok i retested red probe to red black probe to blue and it started out at .9 volts and climbed slowly to 1.5 waited and it climbed to 4.1 so its trying....

[tom66]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

I'm in my uni dorm at the moment, I have nothing to do and don't have to go to anything until 13.00 tomorrow. (Just fresher's week now.)

OK, so I think your fuse is blown. Set your meter to ohms. UNPLUG THE TV (VERY IMPORTANT!!)

Test across the highlighted fuse, you should see less than 2 ohms if the fuse is OK.

If it is blown, suspects are the bridge rectiifers and power MOSFETs. The bridges would be nice and easy. You can replace the fuse, unplug the main power connector (so you've only got the one board plugged in) and see if it then blows the fuse again, if it does, then it is the bridges, otherwise, it is something on the other boards.

It is common for high voltage caps to self charge to a few volts, usually after they have been suddenly discharged. Very strange effect - something to do with dielectric absorption.

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

ohm set to 200 i get .1 to .3 ohms no open circuit..

[tom66]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

OK, so fuse is good. Next suspect is these power resistors.

Pull the board from the TV and check the resistance of each. You can test the leads on the PCB. I think each should be under 20 ohms. If you find one open circuit, then that may be the problem.

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

thanks again yeah its a misterious one. i am at work till 7:00 pm eastern time then to home i can pull power boards to do some component testing but will not be able to power test it till 10 am following morning.

[tom66]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

This test should be done with the board removed.

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

ok 2 of them are 22ohms and other 2 are 5k ohms in circuit test reveals that the 22 ohm pair reads 11.3 each consistent the 5k pair reads 11.3 as well and dmm set to 200 and i pulled one yesterday and the 22 ohm one read exactly 22ohms.

[tom66]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

Are they all marked 22 ohms or otherwise?

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

2 are 22ohms and other 2 are marked 5k ohms

[tom66]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

OK, so the resistors are good. Can you get a picture of the underside of that board with the traces/green side clearly visible? That 3 pin connector - does it go to the main board, or to a power supply board?

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

the 3 pin goes from the line filter to the bottom power supply color codes are red/blue/black camera sucks won't do the text on the boards fer crap..

[tom66]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

How sure are you those resistors are 5k? Looks like two of each in parallel, then tied in series. Test from here to here - should be around 22 ohms.

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

2 of them are clearly marked 22 with the omega symbol ohms and i desoldered the 1 from the other set and discovered it is 22 ohms as well sorry bout that weird thing is 2 of em says f5k then 22ohms then the other pair says 5k 22ohms so your correct anyhow

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

at the resistors i get 11.3 ohms each however if i go from leg from one to the last leg on the other i get exactly 22ohms in series like you said

[tom66]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

The resistors are good, so the problem is the relays aren't being energised. Can you install the board in the TV and check the voltage on each of the three pins of the connector. If you press the power button on the TV, nothing happens?

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

ok power button does not do squat its directly connected to the mainboard which does not get a lick of juice that i can find goin in or out ....red lead to red wire /black lead to black wire reads 53v to 54volts ......

red lead to red/ black lead to blue wire reads 5.1 to 5.6 volts

red lead to blue wire / black to black reads 58 to 58.8 volts
pressing power button on each test does nothing

[tom66]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

I should have been clearer... I've got another way of testing it anyhow. Can you see if there are any components next to these relays? Might be diodes...

[heavymachines]

Re: Vizio VM60P HDTV10A No signs of life except speaker pop when unplugged

yes they are diodes good eye diodes on right test 004 both ways in circuit diodes on left test same way 004 both ways with the dmm set to diode of course...does not seem right should i desolder and retest?