Well, I never found out. I have backed off of my FAS's, I don't do them that much. I never heard the noise otherwise. I'm paranoid about what FAS could be doing to my car, so I've stopped doing them for the most part. The noise really freaked me out, so I may be done. I can spare the 2 mpg i may be losing.

 

I found the following on the Honda web site.
"The IMA™ electric motor works in conjunction with the gasoline engine, and supplies additional torque in assist mode. The motor's ultra-thin design allows it to be mounted between the engine and the transmission. The motor also functions as the generator for the IMA System during deceleration, and as a starter, quickly spinning the engine up to idle speed."

There is no mention of a backup starter. I'd be surprised if there is one. It's something that is likely never to be used through the life of the car.

 

There's definitely a starter motor on the '06 - I heard it and felt it a few weeks ago when the temperature had dipped to well below zero F. You can tell because the engine turns over several times, slowly, before it starts. Feels pretty strange after all those 'instant on' starts.

 

The Honda hybrids *do* have an auxilliary 12v gear reduction starter. On my Accord, I actually heard it used *once* - when the car had been parked outside in -10F this last winter (shortly before I got rid of it). It was strange to hear it, I will say (given that I'd only had the IMA starting the car for 25,000mi) !

The Insight also has the same system (per Xcel's description in an earlier thread, and also on Insight Central), and while I haven't had the undercover off to examine the Civic yet, I know that it has to have the same system as well. Otherwise, there'd be no way to start the car with a drained pack, and it's not good for the traction battery to try and start the car in extremely cold temps (or provide assist, until the car warms up, as we all know)