I am dealing with a really unusual issue and I thought that I would see if anyone out there has any suggestions. The project is a 2006 convertible with a 4.0L and automatic transmission. The foremost consideration is that this car has been flooded. We have taken care of all of the known issues so far, except for this one. I noticed early on that every time the battery was reconnected, there was a loud "thump" that was broadcast through the radio speakers. This occurred with the radio (6 disc CD, AM/FM, 2 speakers each door and one each in rear interior quarter panels). That by itself is something I have never seen before. We sourced a "new" used radio head unit that appears to be fully functional. Here's where it gets crazy. When the radio is turned off or the ignition is turned off with the radio on, there is a loud, high pitched squeal (think household burglar alram) emitted from the speakers. If you turn off the radio, the squeal persists, if you turn off the ignition key it persists, if you remove the ignition key it persists. The only thing we have found that shuts it off once it starts, is to turn the key off, restart the engine and then turn the ignition off. We have very limited access to wiring schematics so that is an issue to factor into the solution. If you have any ideas, I am all ears! Thanks in advance for any help you may be able to provide!
Jim
Jim