service MERCEDES-BENZ SPRINTER 2006 Service Manual

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
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 117

Shift Pressure Shift Valve
When the multiple-disc brake B1 (3) is activated,
the working pressure (p-A) is applied to the end face
of the 1-2 / 4-5 shift pressure shift valve (4) (Fig. 117)
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.Lubrication Pressure Regulating Valve
At the working pressure regulating valve surplus
oil is diverted to the lubrication pressure regulating
valve (1) (Fig. 118), from where the lubrication pres-
sure (p-Sm) is used in regulated amounts to supply
the transmission lubrication system including the
torque converter.
Fig. 117 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. 118 Lubrication Pressure Regulating Valve
1 - LUBRICATION PRESSURE REGULATING VALVE
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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. 119). 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.
120) 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.
121) 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. 119 Shift Pressure Regulating Valve
1 - SHIFT PRESSURE REGULATING VALVE
Fig. 120 Regulating Valve Pressure Regulating
Valve
1 - REGULATING VALVE PRESSURE REGULATING VALVE
Fig. 121 Shift Valve Pressure Regulating Valve
1 - SHIFT VALVE PRESSURE REGULATING VALVE
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 119

REMOVAL
(1) Drain transmission oil by unscrewing oil drain
plug (8) (Fig. 122).
NOTE: If the transmission fluid is burnt or contains
abraded particles, the oil cooler lines and oil cooler
must be flushed out.(2) Move selector lever to position ªPº.
(3) Raise vehicle.
(4) Remove bolt (3) (Fig. 123) and screw (1) hold-
ing the heat shield (2) to the transmission.
(5) Disconnect 13-pin plug connector (1) (Fig. 124).
Turn bayonet lock of guide bushing (2) anti-clock-
wise.
(6) Loosen guide bushing (2) and remove from
transmission housing.
Fig. 122 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
Fig. 123 Remove Heat Shield
1 - SCREW
2 - HEAT SHIELD
3 - BOLT
Fig. 124 Remove Wiring Connector Plug
1 - PLUG CONNECTOR
2 - GUIDE BUSHING
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(7) Detach oil pan (5) (Fig. 125).
(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.
(Refer to 21 - TRANSMISSION/AUTOMATIC
TRANSMISSION - NAG1/ELECTROHYDRAULIC
UNIT - REMOVAL)
(2) Remove solenoid caps (1, 2) (Fig. 126).
(3) Unscrew Torxtsocket bolts (3, 4) (Fig. 126).
NOTE: Pay attention to the different lengths of the
TorxTsocket bolts.
(4) Remove leaf springs (5).
(5) Withdraw solenoid valves (6 - 11) from shift
plate (13).
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).
Fig. 125 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 BUSHINGFig. 126 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
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 121

(8) Note the locations of the major shift valve
group components for assembly reference. (Fig. 127)
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 Regu-
lating ValvesNOTE: 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. 128).
(10) Unscrew Torxtbolts (1) (Fig. 128).
(11) Remove valve housing (2) from valve body (4)
(Fig. 128).
(12) Remove sealing plate (3).
Fig. 127 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 REG-
ULATING 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. 128 Shift Plate Components
1-BOLTS-29
2 - VALVE HOUSING
3 - SEALING PLATE
4 - VALVE BODY
5 - LEAF SPRING
Fig. 129 Solenoid Valve Strainer Locations
1 - SOLENOID VALVE STRAINERS
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(13) Remove the strainers (1, 2) for the modulating
pressure and shift pressure control solenoid valves
(Fig. 129) from the valve housing.
(14) Remove the strainer (1) (Fig. 130) in the inlet
to torque converter lock-up control solenoid valve.
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. 131) and the central strainer (2) for re-installa-
tion. Remove all check balls (1, 3, 4) and the central
strainer (2).
Fig. 130 Converter Lock-up Solenoid Valve Strainer
Location
1 - CONVERTER LOCK-UP SOLENOID STRAINER
Fig. 131 Check Balls and Strainer Location
1 - STEEL CHECK BALLS
2 - CENTRAL STRAINER
3 - STEEL CHECK BALLS
4 - PLASTIC CHECK BALLS
5 - PLAIN DOWEL PIN
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 123

(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. 132). 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.
Fig. 132 Valve Body Components
1 - VALVE BODY 8 - SHIFT VALVE PRESSURE REGULATING VALVE
2 - 1-2/4-5 COMMAND VALVE 9 - B2 SHIFT VALVE
3 - 1-2/4-5 HOLDING PRESSURE SHIFT VALVE 10 - 2-3 HOLDING PRESSURE SHIFT VALVE
4 - 1-2/4-5 SHIFT PRESSURE SHIFT VALVE 11 - 2-3 COMMAND VALVE
5 - 1-2/4-5 OVERLAP REGULATING VALVE, SLEEVE, AND PIS-
TON12 - 2-3 SHIFT PRESSURE SHIFT VALVE
6 - SHIFT PRESSURE REGULATING VALVE 13 - TCC LOCK-UP REGULATING VALVE
7 - REGULATING VALVE PRESSURE REGULATING VALVE 14 - TCC DAMPER VALVE - if equipped
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(18) Remove all valves and springs from the valve
housing (2) (Fig. 133). Check all valves for ease of
movement and shavings.
(19) Remove the pressure supply valve (1) (Fig.
134) from the valve body.ASSEMBLY
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 dismantling,
all parts must be washed and blown out with com-
pressed-air, noting that parts may be blown away.
(1) Install the pressure supply valve (1) (Fig. 135)
into the valve body.
Fig. 133 Valve Housing Components
1 - 2-3 OVERLAP REGULATING VALVE, SLEEVE, AND PISTON 6 - 3-4 SHIFT PRESSURE SHIFT VALVE
2 - VALVE HOUSING 7 - 3-4 OVERLAP REGULATING VALVE, SLEEVE, AND PISTON
3 - SELECTOR VALVE 8 - OPERATING PRESSURE REGULATING VALVE
4 - 3-4 HOLDING PRESSURE SHIFT VALVE 9 - LUBRICATING PRESSURE REGULATING VALVE
5 - 3-4 COMMAND VALVE
Fig. 134 Pressure Feed Valve Location
1 - PRESSURE FEED VALVE
Fig. 135 Pressure Feed Valve Location
1 - PRESSURE FEED VALVE
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 125

NOTE: The sleeves and pistons of the overlap reg-
ulating valves must not be mixed up.
(2) Install all valves and springs from the valve
body (1) (Fig. 136). Check all valves for ease of move-
ment and shavings.
(3) Install the screws to hold the side covers to the
valve body. Tighten the screws to 4 N´m (35 in.lbs.).
Fig. 136 Valve Body Components
1 - VALVE BODY 8 - SHIFT VALVE PRESSURE REGULATING VALVE
2 - 1-2/4-5 COMMAND VALVE 9 - B2 SHIFT VALVE
3 - 1-2/4-5 HOLDING PRESSURE SHIFT VALVE 10 - 2-3 HOLDING PRESSURE SHIFT VALVE
4 - 1-2/4-5 SHIFT PRESSURE SHIFT VALVE 11 - 2-3 COMMAND VALVE
5 - 1-2/4-5 OVERLAP REGULATING VALVE, SLEEVE, AND PIS-
TON12 - 2-3 SHIFT PRESSURE SHIFT VALVE
6 - SHIFT PRESSURE REGULATING VALVE 13 - TCC LOCK-UP REGULATING VALVE
7 - REGULATING VALVE PRESSURE REGULATING VALVE 14 - TCC DAMPER VALVE - if equipped
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