MERCEDES-BENZ SPRINTER 2006 Service Manual

Overlap Regulating Valve
Each shift group is assigned one overlap regulating
valve (1) (Fig. 103). The 1-2 / 4-5 overlap regulating
valve is installed in the shift valve housing; the 2-3
and 3-4 overlap regulating valves are installed in the
valve housing. The overlap regulating valve regulates
the pressure reduction during a shift phase.
Fig. 103 Overlap Regulating Valve
1 - OVERLAP REGULATING VALVE
2 - ANNULAR SURFACE ON OVERLAP REGULATING VALVE
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Command Valve
Each shift group possesses one command valve (3)
(Fig. 104). The 1-2 / 4-5 and 2-3 command valves are
installed in the shift valve housing, the 3-4 command
valve is installed in the valve housing. The command
valve switches the shift group from the stationary
phase to the shift phase and back again.
Fig. 104 Command Valve
1 - HOLDING CLUTCH B1
2 - DRIVING CLUTCH K13 - 1-2/4-5 COMMAND VALVE
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Holding Pressure Shift Valve
Each shift group possesses one holding pressure
shift valve (1) (Fig. 105). The 1-2 / 4-5 and 2-3 hold-
ing pressure shift valves are installed in the shift
valve housing; the 3-4 holding pressure shift valve is
installed in the valve housing. The holding pressure
shift valve allocates the working pressure to one
actuator of a shift group.
Fig. 105 Holding Pressure Shift Valve
1 - HOLDING PRESSURE SHIFT VALVE
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Shift Pressure Shift Valve
Each shift group possesses one shift pressure shift
valve (4) (Fig. 106). The 1-2 / 4-5 and 2-3 shift pres-
sure shift valves are installed in the shift valve hous-
ing; the 3-4 shift pressure shift valve is installed in
the valve housing. It assigns the shift pressure (p-S)
to the activating actuator and the overlap pressure
(p-š) regulated by the overlap regulating valve to the
deactivating actuator.
Lubrication Pressure Regulating Valve
The lubrication pressure regulating valve (1) (Fig.
107) is located in the valve housing of the electrohy-
draulic control module. The valve controls the fluid
to lubricate and cool the mechanical part of thetransmission, and limits the pressure in the torque
converter.
Shift Pressure Regulating Valve
The shift pressure regulating valve (1) (Fig. 108) is
located in the valve housing of the shift plate. It reg-
ulates the shift pressure (p-S).
Fig. 106 Shift Pressure Shift Valve
1 - 1-2/4-5 COMMAND VALVE
2 - DRIVING CLUTCH K13 - HOLDING CLUTCH B1
4 - 1-2/4-5 SHIFT PRESSURE SHIFT VALVE
Fig. 107 Lubrication Pressure Regulating Valve
1 - LUBRICATION PRESSURE REGULATING VALVE
Fig. 108 Shift Pressure Regulating Valve
1 - SHIFT PRESSURE REGULATING VALVE
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Regulating Valve Pressure Regulating Valve
The regulating valve pressure regulating valve (1)
(Fig. 109) is located in the valve housing of the elec-
trohydraulic control module. It regulates the regulat-
ing valve/control valve pressure (p-RV).
Shift Valve Pressure Regulating Valve
The shift valve pressure regulating valve (1) (Fig.
110) is located in the valve housing of the electrohy-
draulic control module. It regulates the shift valve
pressure (p-SV).OPERATION
ELECTRICAL CONTROL UNIT
Signals from the transmission control module
(TCM) are converted into hydraulic functions in the
electric valve control unit (7) (Fig. 111). The RPM
sensors (1, 12), starter interlock contact (9), and
transmission oil temperature sensor (8) of the electric
valve control unit (7) supply the TCM with input sig-
nals. The solenoid valves are controlled by the TCM
and trigger the hydraulic functions.
Fig. 109 Regulating Valve Pressure Regulating
Valve
1 - REGULATING VALVE PRESSURE REGULATING VALVE
Fig. 110 Shift Valve Pressure Regulating Valve
1 - SHIFT VALVE PRESSURE REGULATING VALVE
Fig. 111 Electrical Control Unit
1 - N3 SPEED SENSOR
2 - PLUG CONNECTOR
3 - MODULATING PRESSURE REGULATING SOLENOID
4 - SHIFT PRESSURE REGULATING SOLENOID
5 - 1-2/4-5 SHIFT SOLENOID
6 - 3-4 SHIFT SOLENOID
7 - ELECTRICAL CONTROL UNIT
8 - TRANSMISSION TEMPERATURE SENSOR
9 - STARTER INTERLOCK CONTACT
10 - 2-3 SHIFT SOLENOID
11 - TORQUE CONVERTER LOCK-UP SOLENOID
12 - N2 SPEED SENSOR
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HYDRAULIC CONTROL UNIT
Working Pressure Regulating Valve (Line Pressure or Oper-
ating Pressure)
The working pressure (p-A) is regulated at the
working pressure regulating valve (4) (Fig. 112) in
relation to load (modulating pressure, p-Mod) and
gear (K1 or K2 pressure) (1). The spring in the work-
ing pressure regulating valve sets a minimum pres-
sure level (basic pressure).
Fig. 112 Working Pressure Regulating Valve
1 - PRESSURE FROM K1/K2
2 - END FACE
3 - ANNULAR SURFACE
4 - WORKING PRESSURE REGULATING VALVE
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Torque Converter Lockup Clutch Regulating Valve
The torque converter lockup clutch regulating
valve (6) (Fig. 113) regulates the torque converter
lock-up clutch working pressure (p-TCC) in relation
to the torque converter clutch control pressure (p-S/
TCC). According to the size of the working pressure
(p-A), the torque converter lockup clutch is either
Engaged, Disengaged, or Slipping. When the regulat-
ing valve (6) is in the lower position, lubricating oil
flows through the torque converter and oil cooler (8)
into the transmission (torque converter lockup clutch
unpressurized). In its regulating position (slipping,
torque converter lockup clutch pressurized), a
reduced volume of lubricating oil flows through the
annular passage (7) bypassing the torque converter
and passing direct through the oil cooler into the
transmission. The rest of the lubricating oil is
directed via the throttle ªaº into the torque converter
in order to cool the torque converter lockup clutch.
Fig. 113 Torque Converter Lockup Clutch Regulating Valve
1 - TORQUE CONVERTER LOCK-UP CLUTCH
2 - TORQUE CONVERTER OUTPUT
3 - TORQUE CONVERTER INPUT
4 - LUBRICATION
5 - TORQUE CONVERTER LOCK-UP SOLENOID6 - TORQUE CONVERTER LOCK-UP CLUTCH REGULATING
VA LV E
7 - OIL COOLER
8 - LINE PRESSURE REGULATING VALVE
9 - OIL PUMP
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Overlap Regulating Valve
During the shift phase the pressure (Fig. 114) in
the deactivating shift actuator is regulated in rela-
tion to the engine load (modulating pressure, p-Mod)
and the pressure in the activating actuator. The reg-
ulated pressure is inversely proportional to the trans-
fer capacity of the activating shift actuator (regulated
overlap).
Fig. 114 Overlap Regulating Valve
1 - OVERLAP REGULATING VALVE
2 - ANNULAR SURFACE ON OVERLAP REGULATING VALVE
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Command Valve
When the end face is unpressurized (stationary
phase), the working pressure (p-A) is directed to the
actuated shift element. If the end face of the com-
mand valve (Fig. 115) is subjected to the shift valve
pressure (p-SV) (shift phase), then the shift pressure
(p-S) is switched to the activating element and the
overlap pressure (p-š) is switched to the deactivating
element.
Fig. 115 Command Valve
1 - HOLDING CLUTCH B1
2 - DRIVING CLUTCH K13 - 1-2/4-5 COMMAND VALVE
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Shift Valve Holding Pressure
The holding pressure shift valve (1) (Fig. 116) is
actuated by the pressures present at the end face in
the actuators and a spring. It assigns the working
pressure (p-A) to the actuator with the higher pres-
sure (taking into account the spring force and the
effective surface area). The other element of the shift
group is then unpressurized. The valve switches over
only during the shift phase and only at a certain
pressure ratio between the overlap pressure (p-š)
and the shift pressure (p-S).
Fig. 116 Shift Valve Holding Pressure
1 - HOLDING PRESSURE SHIFT VALVE
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