<ul><li><a href="http://forums.audiworld.com/vag/msgs/13892.phtml">x-post to VAG-COM forum. Input appreciated.</a></li></ul>

You might be able to diagnose it on paper if you can find a description (maybe in Bentley) of how the transmission functions in reverse and first, as compared to drive.

For example, maybe in reverse and first a band is applied to lock a drum and then power is transmitted, as opposed to drive where maybe it's relying on clutches to take off?

Might also be a way to do a pin-out type diagnosise to actuate (or check the resistance of) each of the trans solenoids?

"German Transaxle" in Bend, Oregon are transmission gods and it might be worth giving them a call too.

The problem I have is deciding whether I need to attack the trans for more troubleshooting or if there is a TCU issue. The physical symptoms point to something wrong at the valve body, but the TCU not knowing what codes it stores is throwing me off. I don't know if this is normal behavior for the TCU or if this indicates an internal issue with the TCU.

I would think if it was TCU related, you'd wind up with driveability issues between shifts, or not shifting from one gear to another.

Give the guys at German Transaxle a call and see if they can talk to you about it for a minute. They've got a website.

...exhibiting normal behavior though. No one from Ross-tech has responded to my post.

Wish I could be more help, but I haven't worked on any of these transmissions, nor had to chase driveability issues in them.

You might also try unplugging the harness at the rear of the thrans, and over at the big round plug-in near the driver's side firewall, down low.

There's a tech bulletin about the harness being pulled too tight and that causing problems, but you could also have water/moisture/dirt/corrosion inside these multi-pin connectors.

I don't really think the TCU is bad, and I want to eliminate it from suspecion, but this odd return has me stuck.

1) Fluid level..........checked oka
2) Wiring connectors to trans
3) Wiring to trans
4) Multi-function switch
5) Trans solenoids
6) Trans internals

Or something like that.

...WTF the odd response from the TCU means. I need to figure that out before I do anything else.