GN3433EN V7.fm Page 51 Tuesday, June 19, 2007 9:50 AM
The TCM Calibration Information displays data in five sections: • Customer Modifiable Constant (CMC)—displays current values/states/thresholds of those parameters to which the transmission would react, and that the user—with the proper authorization—could change or modify. • Shift Inhibits—indicates the state of current and history shift inhibits (refer to Data Monitor section) • Calibration—displays static data describing both software and hardware installation • SEM/LRTP and Autodetect Information—displays information related to Shift Energy Management (SEM), Low Range Torque Protection (LRTP), and Autodetect information. • Input/Output Functions and wire information—displays I/O functions and wire states (refer to Data Monitor section).
5–9. DATA BUS TRAFFIC VIEW The real-time data flowing on the vehicle’s databus (J1939, J1708, J1850, GMLAN, or proprietary CEC1 protocol) is viewable in the Data Bus Traffic Viewer. The Data Bus Traffic Viewer presents the data link stream data in raw format and, when available, J1939 TCM Received/Broadcasted messages in engineering units. NOTE: Data Bus Traffic View files are not captured or contained in regular Allison DOC™ snapshots.
In the Engineering Units display, which is only available when connected via J1939, all J1939 TCM-relevant data (messages sent and received by the TCM) are displayed. The user can monitor the data exchange between the transmission controller and other control modules by selecting specific SAE J1939 Messages/Parameters. The data bus viewer can be used with or without Allison DOC™ For PC–Service Tool being in a connected state. When the service tool is connected (the tool is receiving/requesting Messages from/to the TCM), the tool is said to be in ACTIVE mode. Conversely, if the Data Bus Viewer is used without having the service tool communicating with the TCM, the tool is said to be in PASSIVE mode (the tool is physically connected to the vehicle/TCM, but it is only “listening” to all the messages going through the selected data link without requesting data from the TCM). The following table contains all the data communication protocols that, depending upon its availability at the diagnostic connector, could be used to connect Allison 51
