I took 03 Q45 in the other day and had the shop replace the crankshaft and camshaft sensors. Got the car home and now will not turn over / start. It almost sounds like a poor connection or almost dead battery. I checked battery and is fine. So thinking i need to check installers work to see if connections are tight unless you have any other ideas. I had starter replaced early this year.

why not take it back to the shop and have THEM diagnose/fix it?

how did you check the battery?

Checked with voltage meter. To diagnose whats wrong they want to charge me, but of course they will likely say its something else.

Did you check it under a load? Voltage should be a bit above 12VDC at rest... not drop much under 12VDC during starting, and then be somewhere around 14.2VDC while the engine is running. What symptoms were you trying to cure by replacing the sensors?