Section 191 (Automatic Transmission - Diagnostics): Precaution
WARNING: This page is about a different car, the 2004 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Perform the RESET MEMORY (AT initialization) when replacing the automatic transmission assy, or engine assy or the ECM (See PRE-CHECK ).
HINT:
Initialization can not be completed by only disconnecting the battery terminal.