Transmission Control System Architecture

Starting in 2010.5 MY 6R80 is transitioning from an internal TCM to an external PCM (gas applications) or TCM (Diesel applications). Main hardware differences:

• Transmission Range Sensor still 4 bit digital, but the transmission bulkhead connector could not accommodate 4 pins so a micro processor was added to the sensor. This processor converts the 4 bit digital signal into a Pulse Width Modulated (PWM) 125 Hz signal.
• Module temperature sensor has been deleted.

The 6R80 is a 6-speed, step ratio transmission that is controlled by an external PCM (gas engine applications) or TCM (Diesel engine applications). For Diesel the TCM communicates to the Engine Control Module (ECM), ABS Module, Instrument Cluster and Transfer Case Control Module using the high speed CAN communication link. The TCM incorporates a standalone OBD-II system. The TCM independently processes and stores fault codes, freeze frame, supports industry-standard PIDs as well as J1979 Mode 09 CALID and CVN. The TCM does not directly illuminate the MIL, but requests the ECM to do so. The TCM is located outside the transmission assembly. It is not serviceable with the exception of reprogramming.