1974 Brain Box saves the day.
That assumes they spent the money to actually put any potting in at all.
With a real one and you're motivated or curious, you can try replacing the transistor.
Working on fix ECUs... AND FIXING WITH SUCCESS!!!
Several others have found their ECUs to have fake transistors too.
Here's another example of a heat sink that does nothing.
from this post
Stop on in for a cup of coffee