More info from Audi world.
ZF Presents the First 6-speed Automatic Transmission
I've underlined the interesting bits that may be related to the slamming issue.
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Torque converter with novel actuation
In automatic transmissions the torque converter is mainly used to move off the line. Part of the new electronic control system for the transmission is the Stand-by Control /SBC. Instead of having the converter running against the engine with the vehicle standing still (foot on the brake pedal), as was previously the case, the converter is now disconnected from the powertrain so that there is only minimal residual load. This further reduces fuel consumption.
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I suspect that it's this disconnecting/reconnecting of the torque converter that's causing the slam from a rolling stop. Not quite the "novel actuation" I want in my X5. This is the suspected modus operandi. See below for the suspected root cause.
Quote:
Transmission control
The electronic transmission control system is based on the newly developed Adaptive ShIft Strategy /ASIS.
The electronic system is constantly fed with data on the condition of the transmission, operating condition, operator behavior and operator requests. Comprehensive evaluation of these sensor signals permits complex functional structures of the control system. As a result it can react to spontaneous driver action or sudden topographical changes and immediately transmit the optimized shifting points to the attached hydraulic shift unit. In this process, the control system covers innumerable variations of driving style, from very sporty to very economical, derived from the incoming signals.
Practically unnoticed by the driver, the electronic system also adjusts its drive strategies to special conditions, such a city traffic and different load conditions.
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I've seen reports of issues with the sensors feeding the control system ranging from faulty sensors to whacky signals due to low voltage. The low voltage theory is interesting in that it may explain why some owners experience it and not others and why it seems to get better or worse. It may depend on the condition of the battery, alternator and/or electrical load at the time. I'm going to check my battery when I get home tonight and put it on the charger. I'll see if it has any affect on the symptoms.