Dear Elite members, Just to give some background, I wanted to kiss goodbye to pathetic OEM HU and install a new HU bought from aftermarket. HU and other things were ready except for the CANBUS interface or connect2 interface, Which was not easy to source. As a stop gap solution till connects2 interface arrives, me and Installer both tried to switch on the aftermarket HU by pulling out the current OEM HU and using a small light and a wire from each of the holes from the OEM harness to identify which wire carries power on ignition on. After few fights we could locate the wire which carries power on ignition on from original harness and We were able to power on the aftermarket HU successfully, But that is where the fun ends . Now I am not able to start the car. No errors on the MID or no warning lights. But when I crank the car it feels that the car is trying to start, I can hear engine being spun by the starter motor but engine never fires up. Before anyone says, it is not a battery drain out issue as we already checked it. We put the original OEM HU back in place still it refuses to start. I know it is bad, but we did try to push start the car a couple of times and still no go. As a final resort I called up FIAT toll free number and kudos to FIAT the tow vehicle arrived within 20 minutes and now the car is in Adya motors Bangalore. But have to wait impatiently till Monday to find out anything. I would really appreciate if guru's here comment on what could have gone wrong before SAs take me for a ride.