VZ42L No Amber light, no stand by 5v

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

Those values are with power button on. I have been reading a lot of threads and it seems like u33 voltage on pin 3 should be lower than 5v but I don't know what to check from here

[budm]

Re: VZ42L No Amber light, no stand by 5v

They look OK (for variable voltage regulators U2, U3, U8, U33: you add 1.25V to what ever you read on pin 1, number at pin 3 then will be the voltage (WITHIN 2~3%) that should be appearing at pin 3 if the regulator is OK), U10 will not get anything until the 12v is working again. We need to find out next if the main is sending out the PS_ON to turn on the power supply or not.
Post good clear pictures of you power supply board, both sides of the board, and also close up of the connectors so I can read the label next to the connectors.
u33, pin1 is 2.03v, add 1.25v, then pin 3 should be = 1.25 + 2.03 = 3.28v

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

I also followed the service manual and I'm stuck at second leg I do not have 12v at pins 2,3,4.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

They look OK (for variable voltage regulators U2, U3, U8, U33: you add 1.25V to what ever you read on pin 1, number at pin 3 then will be the voltage (WITHIN 2~3%) that should be appearing at pin 3 if the regulator is OK), U10 will not get anything until the 12v is working again. We need to find out next if the main is sending out the PS_ON to turn on the power supply or not.
Post good clear pictures of you power supply board, both sides of the board, and also close up of the connectors so I can read the label next to the connectors.
u33, pin1 is 2.03v, add 1.25v, then pin 3 should be = 1.25 + 2.03 = 3.28v

http://m.flickr.com/#/photos/101877610@N04/
Please let me know if that is not sufficient

[budm]

Re: VZ42L No Amber light, no stand by 5v

How do I down load all those pictures so I can inspect them closely? They are not Hi res. Any way, there is a PS_ON PIN, check the DC voltage between that pin with ref to the chassis ground when TV is OFF and when TV is ON.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

OK when power is off 0.017 volts power on 3.117 Volts working on better pictures now

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

[budm]

Re: VZ42L No Amber light, no stand by 5v

OK, you main board is sending the correct signal to turn on the main power supply section but the main power supply section is not working, that is why you are not getting the 12VDC or the 24VDC (both of them are generated by the same transformer).
What I need next are the good clear resolution of the power supply board, both sides for now.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

[budm]

Re: VZ42L No Amber light, no stand by 5v

OK, SJ does not have one in stock. http://www.shopjimmy.com/vizio-0500-...wer-supply.htm

I need the pictures of the power supply board bottom side, I found pictures for the top side of the board.

[budm]

Re: VZ42L No Amber light, no stand by 5v

Another thing to try is to disconnect the connectors for the 24V that go to the inverter board to see if you will get the 24VDC or not, in case there is shorted circuit in the inverter board.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

ok great is there anything else I should check to verify it just that board? Or i there anything component level that I may be able to check/repair on the PSU. I am going to order the new board but if theres anything else I can look in to for some education value I would love it

[budm]

Re: VZ42L No Amber light, no stand by 5v

Disconnect the cable to go to the inverter board/s to see if the 24v will appear.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v





0 volts with connectors off on the 24V pins

[budm]

Re: VZ42L No Amber light, no stand by 5v

OK, the power supply board is the problem. I will have to trace out those connections on the bottom side of the board and draw up the diagram then show you the test points to check, it will be a long process for me since I do not have the board in front of me.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

That is really great I really appreciate it. I am very interested in gaining knowledge on component level troubleshooting and I really appreciate it. Im in my first year in a NASA apprenticeship program and everything I do outside of works really helps me thank you again

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

Also in case you notice my fuse looks like its missing... It is not i temp put a 6.3 amp fuse in from a different package just untill the correct fuse gets delivered I am measuring 120 on the other side of fuse now . I fixed that first thing

[budm]

Re: VZ42L No Amber light, no stand by 5v

OK, there is a big brown cap laying on its side on the power supply board, take the DC reading right at the two legs of the cap, it should have about 370~400VDC on it when the TV is turn on. Be real careful not to touch anything with your hands and do not let the probes slip.