MERCEDES-BENZ SPRINTER 2005 Service Repair Manual

Fig. 92 Command Valve
1 - HOLDING CLUTCH B1
2 - DRIVING CLUTCH K13 - 1-2/4-5 COMMAND VALVE
Fig. 93 Holding Pressure Shift Valve
1 - HOLDING PRESSURE SHIFT VALVE
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ELECTROHYDRAULIC UNIT (Continued)

Shift Pressure Shift Valve
Each shift group possesses one shift pressure shift
valve (Fig. 94). The 1-2 / 4-5 and 2-3 shift pressure
shift valves are installed in the shift valve housing;
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 (Fig. 95)
is located in the valve housing of the electrohydraulic
control module. The valve controls the fluid to lubri-
cate and cool the mechanical part of the transmis-
sion, and limits the pressure in the torque converter.
Fig. 94 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. 95 Lubrication Pressure Regulating Valve
1 - LUBRICATION PRESSURE REGULATING VALVE
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ELECTROHYDRAULIC UNIT (Continued)

Shift Pressure Regulating Valve
The shift pressure regulating valve (Fig. 96) is
located in the valve housing of the shift plate. It reg-
ulates the shift pressure (p-S).
Regulating Valve Pressure Regulating Valve
The regulating valve pressure regulating valve
(Fig. 97) is located in the valve housing of the elec-
trohydraulic control module. It regulates the regulat-
ing valve pressure (p-RV).Shift Valve Pressure Regulating Valve
The shift valve pressure regulating valve (Fig. 98)
is located in the valve housing of the electrohydraulic
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. 99). The RPM sen-
sors (1, 12), starter interlock contact (9), and trans-
mission 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. 96 Shift Pressure Regulating Valve
1 - PRESSURE FROM CLUTCH K2
2 - ANNULAR SURFACE
3 - SHIFT PRESSURE REGULATING VALVE
Fig. 97 Regulating Valve Pressure Regulating Valve
1 - REGULATING VALVE PRESSURE REGULATING VALVE
Fig. 98 Shift Valve Pressure Regulating Valve
1 - SHIFT VALVE PRESSURE REGULATING VALVE
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ELECTROHYDRAULIC UNIT (Continued)

HYDRAULIC CONTROL UNIT
Working Pressure Regulating Valve (Operating Pressure)
The working pressure (p-A) is regulated at the
working pressure regulating valve (22) (Fig. 100) in
relation to load (modulating pressure) and gear (K1
or K2 pressure). The spring in the working pressure
regulating valve sets a minimum pressure level
(basic pressure).
Torque Converter Lockup Clutch Regulating Valve
The torque converter lockup clutch regulating
valve (6) (Fig. 101) regulates the torque converter
lock-up clutch working pressure in relation to the
torque converter clutch control pressure. According to
the size of the working pressure, the torque converter
lockup clutch is either Engaged, Disengaged, or Slip-
ping. When the regulating valve (6) is in the lower
position, lubricating oil flows through the torque con-
verter and oil cooler (8) into the transmission (torque
converter lockup clutch unpressurized). In its regu-
lating position (slipping, torque converter lockup
clutch pressurized), a reduced volume of lubricating
oil flows through the annular passage (7) bypassingthe torque converter and passing direct through the
oil cooler into the transmission. The rest of the lubri-
cating oil is directed via the throttle9a9into the
torque converter in order to cool the torque converter
lockup clutch.
Fig. 99 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
Fig. 100 Working Pressure Regulating Valve
1 - PRESSURE FROM K1/K2
2 - END FACE
3 - ANNULAR SURFACE
4 - WORKING PRESSURE REGULATING VALVE
Fig. 101 Torque Converter Lockup Clutch
Regulating Valve
1 - TORQUE CONVERTER LOCK-UP CLUTCH
2 - TORQUE CONVERTER OUTPUT
3 - TORQUE CONVERTER INPUT
4 - TORQUE CONVERTER LUBRICATION POINTS
5 - TORQUE CONVERTER LOCK-UP SOLENOID
6 - TORQUE CONVERTER LOCK-UP CLUTCH REGULATING
VA LV E
7 - ANNULAR PASSAGE THROTTLE
8 - OIL COOLER
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ELECTROHYDRAULIC UNIT (Continued)

Overlap Regulating Valve
During the shift phase the pressure (Fig. 102) in
the deactivating shift actuator is regulated in rela-
tion to the engine load (modulating pressure) and the
pressure in the activating actuator. The regulated
pressure is inversely proportional to the transfer
capacity of the activating shift actuator (regulated
overlap).
Command Valve
When the end face is unpressurized (stationary
phase), the working pressure is directed to the actu-
ated shift element. If the end face of the commandvalve (Fig. 103) is subjected to the shift valve pres-
sure (p-SV) (shift phase), then the shift pressure is
switched to the activating element and the overlap
pressure is switched to the deactivating element.
Shift Valve Holding Pressure
The holding pressure shift valve (Fig. 104) is actu-
ated by the pressures present at the end face in the
actuators and a spring. It assigns the working pres-
sure to the actuator with the higher pressure (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).
Shift Pressure Shift Valve
When the multiple-disc brake B1 (3) is activated,
the working pressure (pa) is applied to the end face
of the 1-2 / 4-5 shift pressure shift valve (4) (Fig. 105)
via the command valve (1). Its shift state is main-
tained during the shift phase by substituting the
shift element pressure acting on its end face (and
which is variable during the shift phase) with a cor-
responding constant pressure. When the multi-plate
clutch K1 (2) is activated, the end face of the shift
valve is unpressurized during the stationary and
shift phases, so the shift state is maintained during
the shift phase in this case too.
Fig. 103 Command Valve
1 - HOLDING CLUTCH B1
2 - DRIVING CLUTCH K13 - 1-2/4-5 COMMAND VALVE
Fig. 102 Overlap Regulating Valve
1 - OVERLAP REGULATING VALVE
2 - ANNULAR SURFACE ON OVERLAP REGULATING VALVE
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ELECTROHYDRAULIC UNIT (Continued)

Fig. 104 Shift Valve Holding Pressure
1 - HOLDING PRESSURE SHIFT VALVE
Fig. 105 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
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ELECTROHYDRAULIC UNIT (Continued)

Lubrication Pressure Regulating Valve
At the working pressure regulating valve surplus
oil is diverted to the lubrication pressure regulating
valve (1) (Fig. 106), from where the lubrication pres-
sure (p-Sm) is used in regulated amounts to supply
the transmission lubrication system including the
torque converter.
Shift Pressure Regulating Valve
The shift pressure is determined by the shift pres-
sure regulating solenoid valve and the shift pressure
regulating valve (3) (Fig. 107). In addition, pressure
from the clutch K2 (1) is also present at the annular
surface (2) of the shift pressure regulating valve (3).
This reduces the shift pressure in 2nd gear.Regulating Valve Pressure Regulating Valve
The regulating valve pressure (p-RV) is set at the
regulating valve pressure regulating valve (1) (Fig.
108) in relation to the working pressure (p-A) as far
as the maximum pressure.
Shift Valve Pressure Regulating Valve
The non-constant regulating valve pressure (p-RV)
is regulated to a constant shift valve pressure (p-SV)
at the shift valve pressure regulating valve (1) (Fig.
109) and is used to supply the 1-2 and 4-5 / 3-4 / 2-3
solenoid valves and the torque converter lockup
clutch PWM solenoid valve.
Fig. 106 Lubrication Pressure Regulating Valve
1 - LUBRICATION PRESSURE REGULATING VALVE
Fig. 107 Shift Pressure Regulating Valve
1 - PRESSURE FROM CLUTCH K2
2 - ANNULAR SURFACE
3 - SHIFT PRESSURE REGULATING VALVE
Fig. 108 Regulating Valve Pressure Regulating
Valve
1 - REGULATING VALVE PRESSURE REGULATING VALVE
Fig. 109 Shift Valve Pressure Regulating Valve
1 - SHIFT VALVE PRESSURE REGULATING VALVE
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ELECTROHYDRAULIC UNIT (Continued)

REMOVAL
(1) Move selector lever to position9P9.
(2) Raise vehicle.
(3) Remove bolt (3) (Fig. 110) and screw (1) holding
the heat shield (2) to the transmission.
(4) Loosen guide bushing (2) (Fig. 110) and remove
from transmission housing.
(5) Disconnect 13-pin plug connector (1) (Fig. 111).
Turn bayonet lock of guide bushing (2) anti-clock-
wise.(6) Drain transmission oil by unscrewing oil drain
plug (8) (Fig. 112).
NOTE: If the transmission fluid is burnt or contains
abraded particles, the oil cooler lines and oil cooler
must be flushed out.
(7) Detach oil pan (5).
(8) Remove oil filter (4).
(9) Unscrew Torx socket bolts (3) and remove elec-
trohydraulic control module (2).
DISASSEMBLY
(1) Remove electrohydraulic unit from the vehicle.
(2) Remove solenoid caps (1, 2) (Fig. 113).
(3) Unscrew Torx socket bolts (3, 4) (Fig. 113).
NOTE: Pay attention to the different lengths of the
Torx socket bolts.
(4) Remove leaf springs (5).
(5) Withdraw solenoid valves (6 - 11) from shift
plate (13).
Fig. 110 Remove Heat Shield
1 - SCREW
2 - HEAT SHIELD
3 - BOLT
Fig. 111 Remove Wiring Connector Plug
1 - PLUG CONNECTOR
2 - GUIDE BUSHING
Fig. 112 Remove Electrohydraulic Unit
1 - HEAT SHIELD
2 - ELECTROHYDRAULIC UNIT
3 - BOLT
4 - OIL FILTER
5 - OIL PAN
6 - CLAMPING ELEMENT
7 - BOLT
8 - DRAIN PLUG
9 - DRAIN PLUG GASKET
10 - 13-PIN PLUG CONNECTOR
11 - BOLT
12 - GUIDE BUSHING
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ELECTROHYDRAULIC UNIT (Continued)

NOTE: Check O-rings on solenoid valves for dam-
age and replace if necessary.
(6) Bend away retaining lug on stiffening rib on
transmission oil temperature sensor.
(7) Remove electrohydraulic control module (12)
from the shift plate (13).
(8) Note the locations of the major shift valve
group components for assembly reference (Fig. 114).
NOTE: Pay great attention to cleanliness for all
work on the shift plate. Fluffy cloths must not be
used. Leather cloths are particularly good. After dis-
mantling, all parts must be washed and blown out
with compressed-air, noting that parts may be
blown away.
(9) Unbolt leaf spring (5) (Fig. 115).
(10) Unscrew Torx bolts (1) (Fig. 115).
(11) Remove valve housing (2) from valve body (4)
(Fig. 115).
Fig. 113 Electrical Unit Components
1 - SOLENOID CAP
2 - SOLENOID CAP
3 - BOLT - M6X32
4 - BOLT - M6X30
5 - LEAF SPRING
6 - MODULATING PRESSURE REGULATING SOLENOID VALVE
7 - SHIFT PRESSURE REGULATING SOLENOID
8 - 3-4 SHIFT SOLENOID
9 - TORQUE CONVERTER LOCK-UP SOLENOID
10 - 1-2/4-5 SHIFT SOLENOID
11 - 2-3 SHIFT SOLENOID
12 - ELECTRICHYDRAULIC CONTROL MODULE
13 - SHIFT PLATE
Fig. 114 Shift Valve Group Locations
A - OPERATING AND LUBRICATING PRESSURE REGULATING
VALVES AND 2-3 OVERLAP VALVE
B - 1-2/4-5 SHIFT GROUP AND SHIFT, SHIFT VALVE, AND
REGULATING VALVE PRESSURE REGULATING VALVES
C - 3-4 SHIFT GROUP
D - 2-3 SHIFT GROUP, TCC LOCK-UP AND B2 REGULATING
VA LV E S
Fig. 115 Shift Plate Components
1-BOLTS-29
2 - VALVE HOUSING
3 - SEALING PLATE
4 - VALVE BODY
5 - LEAF SPRING
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ELECTROHYDRAULIC UNIT (Continued)

(12) Remove the strainers for the modulating pres-
sure and shift pressure control solenoid valves (Fig.
116) from the valve housing.
(13) Remove the strainer (1) (Fig. 117) in the inlet
to torque converter lock-up control solenoid valve.(14) Remove sealing plate (3).
NOTE: A total of 12 valve balls are located in the
valve body, four made from plastic (4) and eight
from steel (1, 3).
(15) Note the location of all check balls (1, 3, 4)
(Fig. 118) and the central strainer (2) for re-installa-
tion. Remove all check balls (1, 3, 4) and the central
strainer (2).
(16) Remove the screws holding the side covers to
the valve body and valve housing.
(17) Remove all valves and springs from the valve
body (1) (Fig. 119). Check all valves for ease of move-
ment and shavings.
NOTE: The sleeves and pistons of the overlap reg-
ulating valves must not be mixed up.
(18) Remove all valves and springs from the valve
housing (2) (Fig. 120). Check all valves for ease of
movement and shavings.
(19) Remove the pressure supply valve (1) (Fig.
121) from the valve body.
Fig. 116 Solenoid Valve Strainer Locations
1 - SOLENOID VALVE STRAINERS
Fig. 117 Converter Lock-up Solenoid Valve Strainer
Location
1 - CONVERTER LOCK-UP SOLENOID STRAINER
Fig. 118 Check Balls and Strainer Location
1 - STEEL CHECK BALLS
2 - CENTRAL STRAINER
3 - STEEL CHECK BALLS
4 - PLASTIC CHECK BALLS
5 - PLAIN DOWEL PIN
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ELECTROHYDRAULIC UNIT (Continued)