Anyone change a General Module themselves?
 

My bogus maintenance plan claims not to cover and dealer wants $1000 to swap out the GM. Is there any special coding I need to know or is this a simple plug n' play module for the on board computer to acknowledge?
Dealer want's $200 for diagnosis, so not sure the risk of buying part at $350 to save $500 is worth it if I can't program it. Any links on how to locate/install in my 02 X5 3.0?

Most likely it will need to be programmed. If you already know it's the GM whyis the dealer looking $200 for diagnosis?

I put it with dealer not knowing my maintenance agreement wouldn't cover. They came back w/ the $1000 bill and told me it was the GM. Now my choice is to buy for $300 and install myself or tell dealer to go forward. I've done this before, only last time the dealer didn't get through diagnosis so far as to tear my dash apart. I suspect they've already put in the GM or are prepared to simply plug it and go.

Supposed if it needs to be programmed, I cannot do this, so am stuck ?

You can bet that they will get their "pound of flesh" no matter how you proceed. As just about every module needs to be mated to the vehicle I would say you are stuck with them.