alero 2000 electrical issue

[alero2000canada]

good day to you all
i have an alero 2000 3.4 v6 gl
and the problem started with the gauges going a bit mad and the car not starting.
so i checked all the earth/ground connections,even that tricky one on the engine under the exhaust,they were all fine.
battery was checked and is fully charged and connections all good.

so i ripped out the dash and replaced the ignition switch.
stuck everything back together and still the same.

so i got an OBD reader to see what codes are on the cars brains ( would this be the BCM?)
the OBD reader couldnt find the BCM.we tried several times.not found

so my thoughts is the BCM is toasted,would this be correct or am i missing something here.
please note this car has 280,000 kms on it now

[tw0123]

Did you test the alt? It could be going out but with the battery fully charged it's unlikely...