Code Question

Indicates the sensor signal is greater than the self-test maximum. The IAT sensor maximum is 4.6 volts or -50°C (-58°F).
In other words it it reading reference voltage. I would say you have an open circuit in the signal return wire which is the GY/RD wire although it could be a bad sensor or even the PCM itself. If it is an open circuit in the GY/RD wire I would suspect that it is before it gets to the splice since several other sensors share that circuit also and you are not getting any other codes. Just to check the harness quickly try using a jumper wire on the GY/RD wire at the IAT and just hook it to the GY/RD wire at one of the other sensors that share it like TP,FRP,ECT,DPFE which ever one is easy to get to, then retest and see if code is gone.