[deanewalpole]

Nice to be back!

I now work for LKQ and we often do BMW bits. A colleague yesterday had a customer asking for a module, which we did not do, but the control unit was something we stocked.

Presumably there would of been a back and forth to determine which our customer needed, but it occured to me the difference eludes me.

I have a vague feeling one takes commands from the human driver's inputs and, increasingly, various sensors and the other *sends* commands to mechanical parts to dip or dim etc.

I could be wrong on all of that. Can anyone assist please?