No communication PATS is relatively simple issue. The PATS transciever has a power circuit, a ground circuit and then has both receive and transmit lines. Confirm your power and ground circuits to the transceiver. Then on the TX line you will need a scope to watch the PATS modules request (the instrument cluster (IPC) in your case) the key's identity, which will be followed by the transceiver sending that information.
The transceiver sends a 5v signal to the IPC which the IPC pulls to ground to make the request, the IPC sends a 5v signal to the transceiver which the transceiver pulls to gound to make the reply with the key's identity. The IPC then sends a go/no-go command to the PCM.