2.1 Inputs and Outputs
IntroductionThe 6HP26 Automatic Transmission is a six speed electronically controlled transmission comprising the basic elements of a TCM and main control valve body unit, a torque converter, one solenoid valve and six pressure regulators. Gear selection is achieved by the control of Automatic Transmission Fluid (ATF) flow to operate various internal clutches. The TCM operates the electrical components and provides for the control of gear selection shift pressure that increases refinement and torque converter slip control.
In the event of a system fault the TCM also provides for Failure Mode Effect Management (FMEM) to maintain maximum functional operation of the transmission with a minimum reduction in driver, passenger or vehicle safety. In the event of a total loss of control or electrical power the basic transmission functions Park, Reverse, Neutral and Drive are retained. Also 3rd or 5th gear is retained by the hydraulic system, the gear retained is dependent upon the gear selected at the time of the failure.
The transmission also contains turbine and output shaft speed sensors, an internal P, R, N, D selector shaft position sensor, and a transmission fluid temperature sensor. The TCM also requires information from the gear selector to determine when the driver has initiated manual gear selection. The TCM communicates with other electronic control modules by the controller area network (CAN).
The TCM also provides for legislated transmission diagnostics, which meet the
2.1 Inputs and Outputs