Facing TV Problems? Ask a TV Technician.
Hi and welcome back to JustAnswer,Thank you for the new question and your patience. Should you still need assistance for information purposes only...Initially, would you prefer to follow up / continue with the other expert in your other question? If yes, please click HERE.
Otherwise, please post back which board; main board or power board was replaced? ....the numbers off the board?
And the numbers of this main board please?
If both the previous and the replacement main board are identically numbered as 3647-0012-0150, then "...Could new board be bad??..." would most likely be yes. This is based on the initial information of "...Turns on ok , turn of takes about 25sec. to click off..." provided in the first question posted as compared to the current observations of "...will not power on..."
Strongly consider returning this board for a replacement.
I realize that the above information may perhaps be not what was expected. Unfortunately, there is no quick-n-easy fix and neither is there a workaround; sorry for having to be the bearer of bad news.