I am a Certified Toyota and ASE Master Technician and was in the
first Prius certification class on the West Coast. I have pasted an
announcement from Toyota Technical Information Service, which is not
available to the public. I have also seen on Dealer Daily, also not
available to the public, two announcements which may help shed some
light.
I also took some time today to call a friend at Technical Assistance
and he confirmed for me that it appears that the malfunction was
caused by a corrupt file in the reprogramming function of the
software, and no external causes have been found in any of the ECM's
returned to Toyota thus far. He also mentioned that yes, there is an
unbelievable backlog in shipping replacements due to the fact that
THEY MUST BE MANUFACTURED FIRST! It sounds like your service guy is
giving you the straight dope. Coincidentally, my friend said that the
first reports of an error were from Oregon. That really sounds like
your tech was on the ball, and has done his job well.

Here are the messages from Toyota:

What's New in TIS
Updated: 11/17/2005


ATTENTION: DO NOT USE VERSION 13.1A SCANTOOL SOFTWARE FOR VEHICLE
REPROGRAMMING.

Analysis of recent ECU failures has revealed that version 13.1a
software is at fault. A new software version 13.2a is undergoing
validation and is scheduled to be released in December.

In the mean time, to avoid damaging ECUs, revert all scantools to
version 13.0a immediately. Version 13.1a may only be used for non-
reprogramming diagnostics on 2006 Prius, RAV4 and IS250/350.

From Dealer Daily:

Published on: 11/03/2005 12:00 AM
On October 28, version 13.1a scantool software was released to
dealers via TIS. Although each release is extensively validated prior
to distribution, we have received a number of reports of ECU
reprogramming failure when conducting SSC 50P for 2004-2005 Prius.
In some cases the Engine ECU may be damaged.

As an immediate countermeasure, we are recommending that all dealers
revert to the previous version of scantool software (V13.0a).

Any ECU that appears to fail as a result of reprogramming errors
should not be discarded. We are currently investigating a potential
recovery method for these ECUs. More details will be provided as
information becomes available.

Please advise all technicians to use version 13.0 scantool software
until further notice.



How to Report Feedback



In the event that any anomalies are detected, it is critical that TMS
Service Technology Department be notified immediately by completing
an Electronic Feedback Report. To use this report, go to the
Diagnostics link - Diagnostic Tester Software page on TIS and click
on the "Feedback Report" link. As a reminder, this report can be
used at anytime to report software concerns.

Also from Dealer Daily:
Published on: 11/18/2005 12:00 AM




Title: ECU Damage While Reprogramming with V13.1a Scantool Software

All dealers must ensure they are using scantool software version
13.0a for SSC 50P and all other functions unless performing non-
reprogramming diagnostics on 2006 Prius, 2006 RAV4, or 2006 IS250/350
models.

On November 2nd, a Dealer Daily message admonished all dealers to
immediately revert to software version 13.0a because version 13.1a
was suspected of contributing to an emerging problem with ECUs being
damaged during reprogramming. This was evidenced mostly in the SSC
50P campaign on Prius.

Further analysis has revealed that the software is at fault and a new
version 13.2a is being validated for release in December. To prevent
further damage and possible shortage of ECUs it is imperative that
dealers not use version 13.1a software.



Both versions of software are still available on TIS to ensure non-
reprogramming diagnostic support for 2006 Prius, 2006 RAV4, or 2006
IS250/350 models. The table below describes proper use in more
detail.