Slylardog12345

So i have an 04 silverado, ran and drove great. Drove it to my local tuner to change my tire size, as soon as his tuning software loaded, the guages reset and he told me to crank it. Well it wouldn't crank. The line under the gear indicator showing which gear your in has dissapeared. After i turn the key on, about 30 seconds later the security light comes on, cel doesnt flash when turn key on anymore, when i try to crank it, the dash lights turn off and nothing happens, fuel pump doesnt prime, starter doesnt engage ect, ive checked every possible fuse, none are blown. Jumped starter relay to verify starter is working, security relearn doesnt work, disconnected battery with no luck. I tried a new nuetral safety switch, no luck. The dealer said theres no communication from ect and tcm, but on an 04, the tcm is inside the pcm, so does that mean pcm is bad? I tested some wires coming off the ecm and thwy have 12v and 5v reference, but no communication, i took pcm apart and didnt see any cracked joints or burns, could pcm still be bad? Anything helps