GM Service Manual Online
For 1990-2009 cars only

The following transmission-related indicators and messages may be displayed on the Instrument Panel Cluster (IPC). For a complete listing and description of all vehicle indicators and messages, refer to Indicator/Warning Message Description and Operation.

"High Trans Temp": This message is displayed when the TCM detects a transmission fluid temperature (TFT) equal to or greater than 130°C (266°F) for 5 seconds.