According to the factory wiring diagrams the Navigator is the one with a separate radio amplifier. The Expedition radio amp is part either part of the head unit or the rear integrated control panel. It shows 5 wires connecting the two together - one being a shield wire. My guess is the amp section is in the rear control panel.
Oh thats just f'n great lol..
So i assume ill need to replace the rear control unit in order to correct the issue?
Im waiting for my manual from a member here so i can look all this up
But thank you for investigating this. It made sense that the head unit did all the work since i was not able to physically locate an actual amplifier. in any of the locations
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I have looked at images of the rear controls and it is just that controls. there is not amplifier built into it so since the headphone jacks in stereo I will have to check the righ side speakers i really doubt that both are blown but you never know. i just dont think its outputting to the speaker.
I just was looking to confirm the headunit was all there was, meaning i have to repalce the nav unit. i wish there was a way to test output from head and verify the problem was in the amp of the head unit.