Reply To: Cant find leak in Lexus AC

[Richard Kirshy]

First thing would be to make sure the engine and engine bay is as clean as possible to allow best chance to see the dye.
If leak detection dye has been added, depending on the size of the leak it may take as little as a few minutes to a few weeks to show.
That is unless the leak is located with in the dashboard which would require it to be removed.