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 in Instrument Panel, Gages, and Console.

"Change Trans Fluid": The IPC illuminates the "change trans fluid" message when the PCM determines that the transmission oil should be changed. The PCM sends a message to the IPC requesting illumination. The select button will allow this message to clear it from the DIC display.