Cel light on, brake light on. Code 2177

So who could do this that is not costly to determine issue

You'll need to find a local shop near you that you can develop a relationship with. And -- there's no guarantee it won't be costly! But I can tell you that it appears that you've already spent a bunch of money guessing without results. There's simply no "short cut" or secret to doing the work needed to find out what is wrong. I'm sorry.

Thanks

BY THE WAY -- DO NOT REPLACE THE PCM!!! This is not likely the cause of your problem, but likely the guess of a mechanic who doesn't know what to do next.