I recently inherited a 2008 model Vizio VW37L. The tv came from a relative who had used it up until "it would not turn on one day". I have basic electronics knowledge and have been able to repair TV's in the past with the basic "blown caps" issues and such. However, this particular problem is out of my realm of knowledge. The search results have yielded a few threads dealing with this issue, but only a few that are specific to this power supply and almost none that have a complete resolution of the problem. Hopefully, with the guidance and help from the members here, I can track down this problem.
So far, I have determined that there is no 5v standby power (also, no lighting of the vizio emblem, and no other response whatsoever). I confirmed this by disconnecting all cables from the PSU, with the exception of the main power cord. A DC voltage check, with the meter grounded to the chassis, yielded no power on any of the "cold side" outputs of the PSU. The main fuse, next to the power cord plug on the PSU, has checked good for continuity. Additionally, measurements across the two legs of the large capacitor on the hot side has shown 167 volts. From other posts, it seems my next step is to check the #1 pin on the SMPS for fluctuating voltage. However, I am unsure of exactly which item this is on the board that I have.
Any insight would be appreciated.
So far, I have determined that there is no 5v standby power (also, no lighting of the vizio emblem, and no other response whatsoever). I confirmed this by disconnecting all cables from the PSU, with the exception of the main power cord. A DC voltage check, with the meter grounded to the chassis, yielded no power on any of the "cold side" outputs of the PSU. The main fuse, next to the power cord plug on the PSU, has checked good for continuity. Additionally, measurements across the two legs of the large capacitor on the hot side has shown 167 volts. From other posts, it seems my next step is to check the #1 pin on the SMPS for fluctuating voltage. However, I am unsure of exactly which item this is on the board that I have.
Any insight would be appreciated.
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