audio system completely dead

[EPDM]

Hi,

Bought a project 2002 4.6is which amongst other things has completely deas audio dsp system. The previous owner had god knows what aftermaket stuff in there. I was told the bm54 radio model had been partly submerged in the spare wheel compartment and that it would fine when repalced...yeah right.

I did replace it with a second hand unit and I do sometimes hear the radio for a while when starting up but have no controll over the rest.

As in the navi screen is blank and without power as is all the stuff in the left side luggage compartment.
I have checked the fuses in the glove compartment and the the right rear luggage compartment. They're fine.
Could the blue relay be bad, how to check?


I am missing at least two units in the spare wheel compartment. Anyone know what they may be? Please see pics.


Yes, I know I could through in a chinese system and be done with it. But would like to resurect the system if possible.