I'm wondering if there is a way to test a PCM without swapping in a new one.

I'm working on a truck that's been sitting for a very long time and I'm not sure the PCM is any good, and I'd rather not spend $200 on a PCM I don't need for this thing.

 

Does the WTS light come on when you turn the key?

 

^^^^ Thats the best way to tell. No WTS light.