An Audi tech shop had told me last month my 2002 Audi TT Roadster, 1.8L Base Turbo had fault codes 18011 (Internal Control Module) P1603-35-10 (Failed Self Test-Intermittent), and 18010 (Power Supply Terminal 30) P1602-35-10 (Voltage Too Low-Intermittent), and the ECM probably was going bad. It also had codes 16684 (Random/Multiple Cylinder Misfire, P0300-35-10-Intermittent), and P0301-35-10 (Misfire Detected Cyl1-Intermittent) and P0302-35-10 Misfire Detected Cyl2-Intermittent), so I CAREFULLY replaced the ignition coils (the plugs had only 900 miles on them), and afterwards it would turn over but not start. I pulled the new coils out and put the old ones back in, but same thing (battery is two months new). The Audi tech shop said the ECM was bad and replaced it (ouch!!). I did NOT disconnect the battery before replacing the coils and am wondering if that may have blown the ECM. Thoughts?