Electrical Modules And Components - Design And Function - 5 Of 5: Transmission: Overview

2009 Volvo XC70 BaseSECTION Overview
Fig 1: Identifying Transmission
GLL156311Courtesy of VOLVO CARS CORPORATION

HINT: The shape of the transmission casing differs depending on which engine is included in the driveline.Β 

TF-80SC (TF-80SC AWD) is an electronically controlled 6-speed automatic transmission with Geartronic.

The Geartronic function combines two transmissions in one. One adaptive 6-gear automatic transmission which enables relaxed driving, and a "manually" shifted transmission which enables more active driving with manual shifting. In case of manual shifting, the gear selector is pushed forward to upshift to a higher gear and it's pulled back to downshift to a lower gear. However, in certain situations the Transmission control module (TCM) assumes the gearshifting decisions.

TF-80SC has a lock-up-function on all forward gears except 1st gear. The torque converter has a locked and slipping lock-up-function.

Gearshifts are controlled by an hydraulic operating system. Gearshifts take place without freewheeling and completely automatically in terms of load and speed.

TF-80SC has two planetary train units, a front and a rear, whose shifts are controlled by a number of clutches and brakes. The rear planetary train is of the Ravigneaux type.

The oil level is checked by level pipe (the transmission does not have a conventional dipstick).

The transmission has a total of 8 solenoids that control the hydraulic flow. 6 of these solenoids control the shift process, 1 solenoid controls the torque converter's lock-up function and 1 solenoid controls the system pressure.

The gear selector sensor is integrated in the Transmission control module (TCM). The Transmission control module (TCM) is integrated in the transmission.

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