I got around to installing my OBDII Bluetooth adapter and got some fault codes. Can anyone give me any insight into what they mean?

P1899: Unknown code - More information may be available on the web
P0138: O2 Sensor Circuit High Voltage (Bank 1 Sensor 2)
P0700: Transmission Control System (MIL Request)
P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)

I'm pretty sure that P0138 is due to the fact that the PO removed the cat and there is no rear O2.

The transmission seems to shift fine. It's alittle sluggish to shift out of first when it's cold. But other than that doesn't seem to slip.