67 All door unlock output circuit shorted to ground or voltage. - 24 key cycles
A3 Battery voltage open. - 8 key cycles
AD FCM messages not received. - 4 key cycles
00-00 means end of c-code check

The one that is likely the issue is the AD c-code.... it looks like your FCM is not communicating with the PCM... so you've got an issue with the FCM to PCM connection...

The other issues look like a bad ground, which might also cause the FCM to have a comm. error like that....

 

OK, one wrench that gets thrown in the mix, i have had the key on with no FCM in place while trying things out. i wonder if that is a problem, also i have had the battery unhooked for about 15 mins.

 

That's not good... you need to remove the battery (at least disconnect) before taking out or putting in the FCM..... Might need to follow the service manual procedure for putting it back in..

 

I just pulled the connectors on the PCM, there is no corrosion at all, looks nice.
Pulled the battery for an hour, put everything back together, turned on ignition for 30 seconds to let all modules talk.
As soon as I turned the key on the "light out" indicator glowed.
Now I'm stuck.

I ran the C-codes again, the first one is 21-00.

Electronic tools I have:
Multimeter's
Diablo sport predator
Tuner pro. Software

 

I decided to take apart my Power Dist Module and check it out for bad spots.
It turns out my Power Dist Module was corroded. I should have take pictures before i soldered the wire in there.
I outlined in red where the trace goes, the blue star is where the trace was completely corroded leaving no more copper.
So i chipped off the cover material and soldered a wire to bridge the gap.

Hope this thread can help others in the future.
Its pretty crazy because everything pointed at the FCM being bad.

Good luck gents!!

 

here is the pic!!

 

Good info thanks for posting...I had the problem with driver side low beam headlight and it was a bad FCM.

 

Posted this in the wrong forum, would like to delete but dont know how.