Transmission 9113 · Regulated torque converter lockup clutch The CLC is controlled by a pulse-

Transmission 9113 Regulated torque converter lockup clutch The CLC is controlled by a pulse-width- modulated solenoid valve which converts the The torque converter lockup clutch (CLC) is a pulse-width-modulated input current into an device which eliminates slippage of the appropriate pressure. This pressure activates torque converter and thus contributes to the a CLC control valve. Depending on the pres- optimisation of fuel consumption and to a sure level, the torque converter clutch is ei- sporty style of driving. ther ? activated ? deactivated ? or in regulated operating mode In the regulated phase, a speed differential between the impeller and turbine of ca. 50 rpm is set. As a result, the torsional vibra- tions of the engine are not transferred to the transmission. This procedure optimises shift quality and reduces noise. Design The outer disc carrier (5) is connected to the im-peller (1) via the case shell (7). The inner disc car-rier (6) is connected to the turbine (2). Function When triggered by the ETC control unit, oil pressure produced by the PWM solenoid valve is fed through the input shaft (9) to the pressure chamber behind the piston (11). The piston pushes the disc pack (10) to- 3_16_00 gether and thus permits direct torque trans- mission between the impeller and turbine. 1 – Impeller 2 – Turbine Converter clutch activation depends on the 3 – Stator engine speed and engine load and is only 4 – Stator shaft possible in 5 – Outer disc carrier 2nd gear or higher. 6 – Inner disc carrier 7 – Case shell Note 8 – Overrunning clutch T o pro tect the co nverter,the engine speed is 9 – Input shaft restricted to 4 000 rpm if no driving speed10 – Disc pack signal is present.11 – Piston 3 - 10 Service Information 2002