Conditions for Running the DTC

WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

Ignition voltage is between 8.6-18.0 volts.
The TCM temperature is greater than 0°C (32°F) and less than 240°C (464°F) for greater than 0.25 seconds.
DTC P0634 is not currently active and has not failed in the current key on.