[Oklahoma Wolf]

Two possibilities:

1 - the deck uses a version of the PCI bus not compatible with the 2000 T&C. The steering wheel controls work over the bus via the BCM... if the two aren't speaking the same language, it won't work.
2 - the new deck is defective

#1 is probably the one tripping you up. I personally would have gone with the RBU - a better sounding RDS enabled deck with rear seat audio capability via RF headphones. No idea if the steering wheel controls would work with one.

 

[Oklahoma Wolf]

I am wondering if the radio needs to turn on something in the amp.

The 2000 Infinity system uses four amps bolted to the back of each rear quarter panel speaker and door speaker - they have no connection with the PCI bus.

The RBU uses the newer connectors. You will not find an RDS enabled factory deck with the old 7 pin black and grey connectors unless you go to the European ones, which will not have FM tuning compatible with US/Canadian frequencies.