That code may be due to a missing/noisy speed signal from the compressor.
Examine the electrical connector on the compressor closely. We have seen many broken wires there.

It does have the compressor speed sensor which I will inspect. I was looking at the pressure switch only because it's about $12 whereas the speed sensor seems to be about $175. Hopefully it's just bad wiring. Thanks for the help.

This is just from threads that I've read here, so do your own search, but it seems that the sensor can also accumulate dirt which interferes with the signal, which is another free fix.

I'm glad that my car lacks that particular sensor, although it has its own trouble spots.

If your pressure sensor really is a switch, and I don't know that it is, you can check it with an ohm meter. Pressure switches should be closed (conducting) with the system off, assuming that the system has sufficient refriderant.