I don’t believe that there were 2 ACC systems on the PFL. The lane assist camera did not work with the radar, as far as Pre-Sense Front was concerned. Maybe it did with the extra option of Pre-Sense Basic.
This is what the brochure said about PFL and ACC.
Adaptive cruise control. Automatic distance control (control range for manual transmission between 20-100mph* and for S tronic 0-100mph).* Also includes Stop/Go function only with S tronic. Working within system limits it uses a radar sensor to detect vehicles ahead and maintain this distance by automatically braking and accelerating. 4 distance levels and different driving modes can be selected individually. Also includes Audi Pre-sense front which warns the driver through an enhanced brake assist of any imminent threat of collision with the vehicle in front. Braking action is initiated at speeds below 19mph if there is a danger of collision with a stationary or moving vehicle, to avoid or reduce impact. Only in combination with Colour Driver's Information System (9S6) on SE models
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