2006 MERCEDES-BENZ SPRINTER engine

engaged multiple-disc clutch K3 (12). The planetary
gears (18) turn on the fixed annulus gear (10) and
increase the torque from the sun gear (22) to the
planetary carrier (14). The output shaft (26) con-
nected to the planetary carrier (14) turns at a
reduced speed in the opposite direction to the run-
ning direction of the engine.
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 21

REVERSE GEAR POWERFLOW - LIMP IN
Fig. 14 Reverse Gear Powerflow - Limp In or 4WD Low Range
1 - TORQUE CONVERTER LOCK-UP CLUTCH 14 - CENTER PLANETARY CARRIER
2 - TORQUE CONVERTER TURBINE 15 - REAR PLANETARY CARRIER
3 - TORQUE CONVERTER IMPELLER 16 - TORQUE CONVERTER STATOR
4 - HOLDING CLUTCH B1 17 - FRONT PLANETARY PINION GEARS
5 - HOLDING CLUTCH B3 18 - CENTER PLANETARY PINION GEARS
6 - HOLDING CLUTCH B2 19 - REAR PLANETARY PINION GEARS
7 - DRIVING CLUTCH K1 20 - FREEWHEELING CLUTCH F1
8 - FRONT PLANETARY ANNULUS GEAR 21 - FRONT PLANETARY SUN GEAR
9 - DRIVING CLUTCH K2 22 - CENTER PLANETARY SUN GEAR
10 - CENTER PLANETARY ANNULUS GEAR 23 - REAR PLANETARY SUN GEAR
11 - REAR PLANETARY ANNULUS GEAR 24 - FREEWHEELING CLUTCH F2
12 - DRIVING CLUTCH K3 25 - INPUT SHAFT
13 - FRONT PLANETARY CARRIER 26 - OUTPUT SHAFT
A - ENGINE SPEED D - SECOND GEAR RATIO
B - TRANSMISSION INPUT SPEED E - FIXED PARTS
C - FIRST GEAR RATIO
21 - 22 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

Torque from the torque converter is increased via
the input shaft (25) and all three planetary gearsets
and transferred with reversed direction of rotation to
the output shaft (26) (Fig. 14) and (Fig. 15).
Front Planetary Gear Set
The clutch K1 (7) is shifted. The planetary carrier
(13) and sun gear (21) are connected to each other as
a result. The annulus gear (8) is driven via the input
shaft (25). The planetary gear set is locked and turns
as a unit.
Rear Planetary Gear Set
The planetary carrier (15) is held against the hous-
ing by the engaged multiple-disc holding clutch B3
(5). The annulus gear (11) turns at a reduced speed
due to the mechanical connection to the front plane-
tary carrier (13). The planetary pinion gears (19)turn between the annulus gear (11) and the sun gear
(23). The direction is reversed by the held planetary
carrier (15) so that the sun gear (23) turns in the
opposite direction to the running direction of the
engine.
Center Planetary Gear Set
The annulus gear (10) is held against the housing
by the multiple-disc holding clutch B3 (5) via the
mechanical connection to the planetary carrier (15).
The sun gear (22) turns backwards due to the
engaged multiple-disc clutch K3 (12). The planetary
gears (18) turn on the fixed annulus gear (10) and
increase the torque from the sun gear (22) to the
planetary carrier (14). The output shaft (26) con-
nected to the planetary carrier (14) turns at a
reduced speed in the opposite direction to the run-
ning direction of the engine.
Fig. 15 Reverse Gear Powerflow - Limp In
1 - TORQUE CONVERTER LOCK-UP CLUTCH 14 - CENTER PLANETARY CARRIER
2 - TORQUE CONVERTER TURBINE 15 - REAR PLANETARY CARRIER
3 - TORQUE CONVERTER IMPELLER 16 - TORQUE CONVERTER STATOR
4 - HOLDING CLUTCH B1 17 - FRONT PLANETARY PINION GEARS
5 - HOLDING CLUTCH B3 18 - CENTER PLANETARY PINION GEARS
6 - HOLDING CLUTCH B2 19 - REAR PLANETARY PINION GEARS
7 - DRIVING CLUTCH K1 20 - FREEWHEELING CLUTCH F1
8 - FRONT PLANETARY ANNULUS GEAR 21 - FRONT PLANETARY SUN GEAR
9 - DRIVING CLUTCH K2 22 - CENTER PLANETARY SUN GEAR
10 - CENTER PLANETARY ANNULUS GEAR 23 - REAR PLANETARY SUN GEAR
11 - REAR PLANETARY ANNULUS GEAR 24 - FREEWHEELING CLUTCH F2
12 - DRIVING CLUTCH K3 25 - INPUT SHAFT
13 - FRONT PLANETARY CARRIER 26 - OUTPUT SHAFT
A - ENGINE SPEED D - SECOND GEAR RATIO
B - TRANSMISSION INPUT SPEED E - FIXED PARTS
C - FIRST GEAR RATIO
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 23

directed via the command valve (5) onto clutch K1
(6).
Simultaneously the clutch B1 (7) is subjected to
overlap pressure by the overlap regulating valve (2).
The pressure in the clutch B1 (7) as it disengages is
controlled during the shift phase depending on
engine load by the modulating pressure and the
applying clutch pressure (the shift pressure in clutch
K1). The controlled pressure in clutch B1 (7) is
inversely proportional to the capacity of the clutch
being engaged. The rising shift pressure (p-S) at
clutch K1 (6) acts on the annular face of the overlap
regulating valve (2) and reduces the overlap pressure
regulated by the overlap regulating valve (2). When a
corresponding pressure level is reached at the hold-
ing pressure shift valve (4), this valve switches over.
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 27

Simultaneously, the pressure in the releasing
clutch, K1 (6), is regulated at the 1-2/4-5 overlap
valve (2). The pressure in the K1 clutch as it disen-
gages is controlled during the shift phase depending
on engine load, via the modulating pressure
(p-MOD), and the shift pressure in clutch B1 (7). The
increasing shift pressure in clutch B1, which also
acts on the end face of the overlap valve, reduces the
overlap pressure.
21 - 32 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

Gear Shift N to D (1st gear) - Engine Started
With the engine started (Fig. 23) and the gearshift
lever in the NEUTRAL or PARK positions, holding
clutch B1 (1) and driving clutch K3 (4) are applied
and the various valves in the 1-2/4-5 shift group are
positioned to apply pressure to the holding clutch B2.
Fig. 23 Engine Started
1 - HOLDING CLUTCH B1 11 - PRESSURE HOLDING VALVE
2 - DRIVING CLUTCH K1 12 - 3-4 HOLDING PRESSURE SHIFT VALVE
3 - HOLDING CLUTCH B3 13 - 3-4 COMMAND VALVE
4 - DRIVING CLUTCH K3 14 - 3-4 SHIFT PRESSURE SHIFT VALVE
5 - HOLDING CLUTCH B2 PISTON 15 - 3-4 OVERLAP REGULATING VALVE
6 - HOLDING CLUTCH B2 PISTON OPPOSING FACE 16 - BALL VALVE
7 - SHIFT PRESSURE REGULATING SOLENOID 17 - 1-2/4-5 COMMAND VALVE
8 - SHIFT PRESSURE REGULATING VALVE 18 - 1-2/4-5 COMMAND VALVE
9 - SHIFT VALVE B2 19 - BALL VALVE
10 - 3-4 SHIFT SOLENOID
21 - 36 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

DIAGNOSIS AND TESTING
AUTOMATIC TRANSMISSION
CAUTION: Before attempting any repair on a NAG1
automatic transmission, check for Diagnostic Trou-
ble Codes with the appropriate scan tool.
Transmission malfunctions may be caused by these
general conditions:
²Poor engine performance.
²Improper adjustments.
²Hydraulic malfunctions.
²Mechanical malfunctions.
²Electronic malfunctions.
²Transfer case performance (if equipped).
Diagnosis of these problems should always begin
by checking the easily accessible variables: fluid level
and condition, gearshift cable adjustment. Then per-
form a road test to determine if the problem has been
corrected or if more diagnosis is necessary.
PRELIMINARY
Two basic procedures are required. One procedure
for vehicles that are drivable and an alternate proce-
dure for disabled vehicles (will not back up or move
forward).
VEHICLE IS DRIVABLE
(1) Check for transmission fault codes using the
appropriate scan tool.
(2) Check fluid level and condition.
(3) Adjust gearshift cable if complaint was based
on delayed, erratic, or harsh shifts.
(4) Road test and note how transmission upshifts,
downshifts, and engages.
VEHICLE IS DISABLED
(1) Check fluid level and condition.(2) Check for broken or disconnected gearshift
cable.
(3) Check for cracked, leaking cooler lines, or loose
or missing pressure-port plugs.
(4) Raise and support vehicle on safety stands,
start engine, shift transmission into gear, and note
following:
(a) If propeller shaft turns but wheels do not,
problem is with differential or axle shafts.
(b) If propeller shaft does not turn and transmis-
sion is noisy, stop engine. Remove oil pan, and
check for debris. If pan is clear, remove transmis-
sion and check for damaged driveplate, converter,
oil pump, or input shaft.
(c) If propeller shaft does not turn and transmis-
sion is not noisy, perform hydraulic-pressure test to
determine if problem is hydraulic or mechanical.
ROAD TESTING
Before road testing, be sure the fluid level and con-
trol cable adjustments have been checked and
adjusted if necessary. Verify that all diagnostic trou-
ble codes have been resolved.
Observe engine performance during the road test.
A poorly tuned engine will not allow accurate analy-
sis of transmission operation.
Operate the transmission in all gear ranges. Check
for shift variations and engine flare which indicates
slippage. Note if shifts are harsh, spongy, delayed,
early, or if part throttle downshifts are sensitive.
Slippage indicated by engine flare, usually means
clutch, overrunning clutch, or line pressure problems.
A slipping clutch can often be determined by com-
paring which internal units are applied in the vari-
ous gear ranges. The Clutch Application chart
CLUTCH APPLICATION provides a basis for analyz-
ing road test results.
CLUTCH APPLICATION
GEAR RATIO B1 B2 B3 K1 K2 K3 F1 F2
1 3.59 X* X X* X X
2 2.19 X X X* X
3 1.41 X X X
4 1.00 X X X
5 0.83 X X X X*
N N/A X X
R 3.16 X* X X X
R - Limp In 1.93 X X X
* = The shift components required during coast.
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 39

AUTOMATIC TRANSMISSION
CONDITION POSSIBLE CAUSES CORRECTION
MAXIMUM SPEED 30
km/h1. Speed Control 30 Actuated. 1. Instruct Customer.
ENGINE DIES WHEN
TRANSMISSION IS SHIFT-
ED INTO GEAR, ALSO
NOISES IN N AND/OR P1. PWM Valve Blocked. 1. Replace Valve.
2. Torque Converter Lock Up Con-
trol Valve Locked.2. Enable Movement of Valve,
Remove Particle.
LEVER IN ªPº POSITION
BLOCKED (BRAKE ACTI-
VATED)1. No Vacuum Brake Booster After
Long Immobilization, Brake Pedal
Not Fully Applied/Hard Pedal.1. Check Vacuum/ Tightness of
Brake Booster.
2. No Stoplamp Switch Signal (no
DTC IN ECM).2. Check Contact to Stoplamp
Switch. Replace Switch if Nec-
essary.
GRUMBLING, DRONING,
JERKING WHEN TCC IS
ENGAGED1. Slip Speed TCC to Low. 1. Switch Off Torque Converter
Lock Up Using DRBT. If Com-
plaint Is Not Reproduced After-
wards, Replace PWM Valve,
Set Adaption Values to Zero.
HOWLING, HUMMING
ABOVE 4000 RPM IN
EACH GEAR1. Oil Filter Blocked. 1. Replace Oil Filter.
2. Oil Pump. 2. Replace Oil Pump.
WHINING, SINGING 1. Gear Set Noises in 1st, 2nd, 5th
Gear.1. Replace Transmission..
2. Intermediate Bearing Of The
Drive Shaft At 0 km/h, Only When
Cold.2. Replace Intermediate Bear-
ing of the Drive Shaft.
9CLACKº NOISE FROM
CENTER SHIFT AREA
WHEN STOPPING OR
STARTING1. Park Lock Solenoid. 1. Replace Shift Lever Assem-
bly.
CRACKING NOISE WHEN
LOAD CYCLE1. Stick - Slip Between Joint Flange
and Collar Nut.1. Install Zinc Coated Collar
Nut Together With Washer.
CHATTERING IN CENTER
CONSOLE SHIFT WHILE
ACCELERATING1. Bushing Shift Shaft Has Too
Much Clearance.1. Replace Shifter Lever and
Cover Plate.
HARD 2-3 UPSHIFT
WHEN STEPPING OFF
THE ACCELERATOR PED-
AL1. Response Characteristic Control
Loop.1. Install K2 Disc Spring.
UPSHIFT 2-3, 3-4 SLIP-
PING1. Spring of Regulating Valve Pres-
sure control Valve Broken.1. Replace Spring.
HARD 2-1 DOWNSHIFT
WHEN COMING TO A
STOP1. Transmission (2-1 downshift) Not
Adapted.1. Re-adapt Transmission.
2. TCM Software Data. 2. Flash TCM.
3. Free Wheeling Clutch F1 Defec-
tive.Replace Free Wheeling Clutch
F1.
21 - 40 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA