Chosen Solution

I have a Sony KDL-46z4100 that won’t show a red stand-by light at all. TV will power on with a green light, but only with vertical lines, no sound and no ability to change the input or channels. I’ve purchased a few pre-owned boards, main boards, t-con boards and power supply boards off Ebay with no luck getting a standby light or the lines off the screen. Any suggestions on this would be greatly appreciated. Thanks

Hi, Don’t know the answer but looking at the service manual a lot of the circuits rely on the Standby power 3.3V to work or at least be there to verify that things are OK, not just the Standby LED. On p.75 of the manual you’ll find the schematic of the power board. It is very faint and my eyes aren’t what they used to be but I think that the Standby 3.3V leaves the power board on connector CN???? pin 3, shown on the lower right side of the circuit. You may have to start there and either trace back into the power board to find out why it is not there or if it is there, out from the power board following the myriad paths of the Standby 3.3V power feed to check that it is where it is supposed to be. Since you have changed the boards, (assuming that they were all OK) it may be a wiring problem between the boards, but this is just a guess on my part. Hopefully a start.