Radio gone haywire

[White ls400]

This morning i went to turn the radio on and there was no sound so i tried a cd and there was no sound either then a few minutes later the sound came on for a second then went back off and i havnt been able to get it the work since. Anyone got an ideas what going on? Iv checked the fuse(radio fuse 7.5amp under steering column) and its good but i didnt think that would be it because the display still comes on the screen
By the ways its a 90model LS

 

[Lextreme II]

Sounds like something is loose.... Check the amp too.

 

[White ls400]

is there 2 amps?
One behind the rear seat(is this the finned block of aluminum with pioneer stamped on because it doesn't really look like an amp to me?) and the other one under the c.d. player i think i remember reading?
correct me if im wrong because most likely i am

 

[White ls400]

Ok i dont think it is the amp now because i was told to turn the volume right up and see if i can hear anything and i could faintly. Which leads me to think my phone may be causing the radio to to mute(never gets used so i dont care what happens to it) So could anyone tell me if these cars come with a phone transceiver factory that i can bypass or would it be easier cutting the mute wire behind the radio any suggestions would be greatly appreciated.

 

[1UZPWR]

do you have a built in phone?

take out the left rear trim on the trunk.

there's a junction block in there. the hardness for the built in phone piggybacks that connection. check for water leaks or condensation in that area. unplug the connectors and check for corrosion.

one of the local lexus dealerships had that problem with an early LS (I think it was a 92) and that was the exact problem, and there was a minor water leak, that had caused some corrosion on one of the pins, and caused the head unit to receive a mute signal