You need a scan tool to access PCM data stream. You can look at the raw serial data with PicoScope, but it would be like listening to a PC modem hooking up. You know its talking, but you have no idea what it's saying.
You'll see the data pulses. That can be useful if your scan tool will not communicate. You'll know the vehicle is sending data, but that's all.
There are many options for scan tools. Some are PC based. These options and functionality will be different depending on your world region.