
AUTO TRANS DIAGNOSIS - 722 SERIES
Article Text (p. 4)
1996 Mercedes-Benz C220
Copyright © 1998 Mitchell Repair Information Company, LLC
Wednesday, January 26, 2000 12:03PM
Fig. 2: Transmission Component ID (722.5 Series Transmission)
Courtesy of Mercedes-Benz of North America.
VALVE BODY
Valve body receives inputs from selector lever position, mode
selector switch, accelerator pedal position (control pressure), intake
manifold vacuum, kickdown function (if activated) and vehicle speed.
Depending on operating conditions, oil flow is controlled to various
points in transmission and pressure is adapted to requirements.
PRIMARY & SECONDARY PUMP
Primary Pump
Primary pump is housed in front transmission cover and is
driven by engine through torque converter. Primary pump operates as
long as engine is turning, and supplies pressurized oil to entire
hydraulic system. Drive of secondary pump is switched off by cut-off
piston, by means of primary pump pressure.
Secondary Pump
Secondary pump is required only for towing and tow-starting
vehicle. It is designed as an external gear pump and is positioned in