ABS MERCEDES-BENZ SPRINTER 2006 Service Manual

rear A/C control module. The temperature of the cir-
culated internal air of the rear compartment is mea-
sured by a temperature sensor located in the rear
evaporator unit. The value of the temperature sensor
is compared in the rear A/C control module with an
adjusted value at the rear A/C temperature control.
The rear A/C temperature control cannot be
repaired and, if faulty or damaged, it must be
replaced.
DIAGNOSIS AND TESTING
REARA/CTEMPERATURE CONTROL
Before testing the rear A/C temperature control,
verify that the front A/C system is operating correctly
by performing the ATC Function Test using the
DRBIIItscan tool. Use a volt/ohmmeter to test the
control. For circuit descriptions and diagrams, refer
to the appropriate wiring information. The wiring
information includes wiring diagrams, proper wire
and connector repair procedures, details of wire har-
ness routing and retention, connector pin-out infor-
mation and location views for the various wire
harness connectors, splices and grounds.
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, impact sensor, or instrument panel com-
ponent diagnosis or service. Disconnect and isolate
the battery negative (ground) cable, then wait two
minutes for the system capacitor to discharge
before performing further diagnosis or service. This
is the only sure way to disable the supplemental
restraint system. Failure to take the proper precau-
tions could result in accidental airbag deployment.
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the wire harness connector from the
rear A/C temperature control.
(3) Check for continuity between terminal 9 and
terminals 3 and 5 of the A/C temperature control. In
all instances, there should be continuity.
NOTE: To check the switch's internal circuits, con-
nect the positive lead of the ohmmeter to terminal 9
and the negative lead to terminals 3 and 5. To
check the switches integral light emitting diode,
reverse the ohmmeter leads.
(4) Check for resistance between terminal 3 and 5
of the A/C temperature control as you move the con-
trol to each temperature position. Resistance should
be present and should change for each position.(5) If OK, test and repair the rear A/C tempera-
ture control wire harness circuits. If not OK, replace
the faulty rear A/C temperature control.
REMOVAL
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, impact sensor, or instrument panel com-
ponent diagnosis or service. Disconnect and isolate
the battery negative (ground) cable, then wait two
minutes for the system capacitor to discharge
before performing further diagnosis or service. This
is the only sure way to disable the supplemental
restraint system. Failure to take the proper precau-
tions could result in accidental airbag deployment.
NOTE: The rear A/C temperature control is used
only on models with the optional rear A/C unit.
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the accessory switch panel from the
instrument panel (Refer to 23 - BODY/INSTRU-
MENT PANEL/ACCESSORY SWITCH BEZEL -
REMOVAL).
(3) Disconnect the wire harness connector from the
rear A/C temperature control (Fig. 18).
(4) Disengage the retaining tabs and remove the
rear A/C temperature control from the accessory
switch panel.
Fig. 18 Rear A/C Temperature Control
1 - WIRE HARNESS CONNECTOR
2 - REAR A/C TEMPERATURE CONTROL
3 - ACCESSORY SWITCH PANEL
VACONTROLS - REAR 24 - 39

INSTALLATION
(1) Install the rear A/C temperature control into
the accessory switch panel. Make sure the retaining
tabs are fully engaged.
(2) Connect the wire harness connector to the rear
A/C temperature control.
(3) Install the accessory switch panel (Refer to 23 -
BODY/INSTRUMENT PANEL/ACCESSORY
SWITCH BEZEL - INSTALLATION).
(4) Reconnect the negative battery cable.
TEMPERATURE SENSOR
DESCRIPTION
The rear temperature sensor (Fig. 19) provides an
air outlet temperature signal to the rear A/C control
module through a two-wire harness lead and connec-
tor.
The rear temperature sensor is located in the rear
A/C evaporator housing.
OPERATION
The rear A/C temperature sensor is a variable
resistor that operates on a five-volt reference signal
sent to it by the rear A/C control module. The resis-
tance in the sensor changes as air temperature
changes. Based upon the resistance in the sensor, a
specific voltage on the temperature sensor signal cir-
cuit is returned to the rear A/C control module,
which is programmed to correspond to a specific tem-
perature.
The rear A/C temperature sensor cannot be
adjusted or repaired and, if faulty or damaged, it
must be replaced.
DIAGNOSIS AND TESTING
REAR TEMPERATURE SENSOR
(1) Disconnect and isolate the negative battery
cable.
(2) Disconnect the wire harness connector from the
rear temperature sensor.
(3) Measure the resistance of the rear temperature
sensor. At ±40É C (±40É F), the sensor resistance
should be approximatley 336 kilohms. At 55É C (131É
F), the sensor resistance is should be approximaytly
25 kilohms. The rear sensor resistance should read
between these two values.
(4) If OK, test and repair the rear temperature
sensor wire harness circuits. Refer to the appropriate
wiring information for rear temperature sensor cir-
cuit descriptions and for complete HVAC wiring dia-
grams. If not OK, replace the faulty temperature
sensor (Refer to 24 - HEATING & AIR CONDITION-
ING/CONTROLS - REAR/TEMPERATURE SENSOR
- REMOVAL).
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the air filter from the rear A/C evapo-
rator housing (Refer to 24 - HEATING & AIR CON-
DITIONING/DISTRIBUTION - REAR/AIR FILTER -
REMOVAL).
(3) Reach up into the rear A/C evaporator housing
and disconnect the wire harness connector from the
rear temperature sensor (Fig. 20).
(4) Carefully remove the rear temperature sensor
from the bracket.
Fig. 19 Rear Temperature Sensor
1 - REAR TEMPERATURE SENSOR
2 - WIRE HARNESS CONNECTOR
24 - 40 CONTROLS - REARVA

DISTRIBUTION - FRONT
TABLE OF CONTENTS
page page
AIR FILTER
REMOVAL.............................45
INSTALLATION.........................45
AIR OUTLETS
REMOVAL.............................45
INSTALLATION.........................46
BLOWER MOTOR
REMOVAL.............................47
INSTALLATION.........................47
DEFROSTER DUCTS
REMOVAL.............................47
INSTALLATION.........................47FLOOR DISTRIBUTION DUCTS
REMOVAL.............................47
INSTALLATION.........................48
HVAC HOUSING
REMOVAL.............................48
DISASSEMBLY.........................49
ASSEMBLY............................50
INSTALLATION.........................50
INSTRUMENT PANEL DUCTS
REMOVAL.............................51
INSTALLATION.........................51
AIR FILTER
REMOVAL
(1) Remove the insulation blanket from the venti-
lation housing in the engine compartment (Fig. 1).
(2) Open the locking clips at the front and rear of
the ventilation housing.
(3) Slide the ventilation housing cover in the direc-
tion of the arrow shown.
(4) Remove the air filter.
INSTALLATION
(1) Install the air filter into the ventilation hous-
ing.(2) Install the ventilation housing cover
(3) Close the locking clips at the front and rear of
the ventilation housing.
NOTE: The locking tabs should retain the ventila-
tion housing cover securely.
(4) Install the insulation blanket onto the ventila-
tion housing.
AIR OUTLETS
REMOVAL
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, impact sensor, or instrument panel com-
ponent diagnosis or service. Disconnect and isolate
the battery negative (ground) cable, then wait two
minutes for the system capacitor to discharge
before performing further diagnosis or service. This
is the only sure way to disable the supplemental
restraint system. Failure to take the proper precau-
tions could result in accidental airbag deployment.
(1) Disconnect and isolate the battery negative
cable.
(2) If servicing the driver side air outlets, remove
the instrument cluster bezel (Refer to 23 - BODY/IN-
STRUMENT PANEL/CLUSTER BEZEL -
REMOVAL).
(3) If servicing the passenger side air outlets,
remove the passenger side airbag (Refer to 8 - ELEC-
TRICAL/RESTRAINTS/PASSENGER AIRBAG -
REMOVAL).
Fig. 1 Air Filter Element
1 - VENTILATION HOUSING INSULATION BLANKET
2 - LOCKING CLIP (2)
3 - AIR FILTER
VADISTRIBUTION - FRONT 24 - 45

CAUTIONS
CAUTION: Never add R-12 to a refrigerant system
designed to use R-134a. Do not use R-12 equipment
or parts on a R-134a A/C system. These refrigerants
are not compatible and damage to the A/C system
will result.
CAUTION: Never use R-12 refrigerant oil in a A/C
system designed to use R-134a refrigerant oil.
These refrigerant oils are not compatible and dam-
age to the A/C system will result.
CAUTION: The use of A/C system sealers may
result in damage to A/C refrigerant recovery/evacu-
ation/recharging equipment and/or A/C system.
Many federal, state/provincial and local regulations
prohibit the recharge of A/C systems with known
leaks. DaimlerChrysler recommends the detection
of A/C system leaks through the use of approved
leak detectors and fluorescent leak detection dyes.
Vehicles found with A/C system sealers should be
treated as contaminated and replacement of the
entire A/C refrigerant system is recommended. A/C
systems found to be contaminated with A/C system
sealers, A/C stop-leak products or seal conditioners
voids the warranty for the A/C system.
CAUTION: Recover the refrigerant before opening
any fitting or connection. Open the fittings with
caution, even after the system has been dis-
charged. Never open or loosen a connection before
recovering the refrigerant.
CAUTION: If equipped, do not remove the second-
ary retention clip from any spring-lock coupler con-
nection while the refrigerant system is under
pressure. Recover the refrigerant before removing
the secondary retention clip. Open the fittings with
caution, even after the system has been dis-
charged. Never open or loosen a connection before
recovering the refrigerant.
CAUTION: The internal parts of the A/C system will
remain stable as long as moisture-free refrigerant
and refrigerant oil is used. Abnormal amounts of
dirt, moisture or air can upset the chemical stability.
This may cause operational troubles or even seri-
ous damage if present in more than very small
quantities. Before disconnecting a component,
clean the outside of the fittings thoroughly to pre-
vent contamination from entering the refrigerant
system. Keep service tools and the work area clean.
Do not open the refrigerant system or uncap areplacement component until you are ready to ser-
vice the system. Immediately after disconnecting a
component from the refrigerant system, seal the
open fittings with a cap or plug. This will prevent
contamination from entering the A/C system.
CAUTION: Refrigerant oil will absorb moisture from
the atmosphere if left uncapped. Do not open a
container of refrigerant oil until you are ready to
use it. Replace the cap on the oil container immedi-
ately after using. Store refrigerant oil only in a
clean, airtight, and moisture-free container.
CAUTION: Do not overcharge the refrigerant sys-
tem. Overcharging will cause excessive compressor
head pressure and can cause compressor noise
and A/C system failure.
DIAGNOSIS AND TESTING
REFRIGERANT SYSTEM LEAKS
WARNING: R-134a service equipment or vehicle A/C
system should not be pressure tested or leak tested
with compressed air. Mixture of air and R-134a can
be combustible at elevated pressures. These mix-
tures are potentially dangerous and may result in
fire or explosion causing property damage, per-
sonal injury or death.
Avoid breathing A/C refrigerant and lubricant vapor
or mist. Exposure may irritate eyes, nose and
throat. Use only approved service equipment meet-
ing SAE requirements to discharge R-134a system.
If accidental system discharge occurs, ventilate
work area before resuming service.
If the A/C system is not cooling properly, determine
if the refrigerant system is fully charged with
R-134a. This is accomplished by performing a Refrig-
erant System Charge Level test (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING -
DIAGNOSIS AND TESTING - REFRIGERANT SYS-
TEM CHARGE LEVEL) or by completely evacuating
and recharging the A/C system. If the A/C liquid line
pressure is found to be less than 345 kPa (50 psi)
while performing the Refrigerant System Charge
Level test, proceed to the System Empty procedure
below. If liquid line pressure is found to be greater
than 345 kPa (50 psi), proceed to the System Low
procedure. If the refrigerant system is empty or low
in refrigerant charge, a leak at any line fitting or
component seal is likely. A review of the fittings,
lines and components for oily residue is an indication
of the leak location. To detect a leak in the refriger-
ant system, perform one of the following procedures
as indicated by the symptoms.
24 - 62 PLUMBINGVA

(6) Remove the tape or plugs from the condenser
inlet port and the discharge line fitting.
(7) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the discharge line fit-
ting.
(8) Connect the discharge line fitting to the con-
denser inlet port.
(9) Install the nut that secures the discharge line
fitting to the condenser. Tighten the nut to 33 N´m
(24 ft. lbs.).
(10) Install the grille (Refer to 23 - BODY/EXTE-
RIOR/GRILLE - INSTALLATION).
(11) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE)
(12) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM CHARGE)
(13) Reconnect the negative battery cable.
A/CEVAPORATOR
DESCRIPTION
The A/C evaporator for the heating-A/C system is
located within the HVAC housing, behind the instru-
ment panel (Fig. 8). The A/C evaporator is positioned
within the HVAC housing so that all air entering the
housing must pass over the evaporator fins before it
is distributed through the heating-A/C system ducts
and outlets. However, air passing over the evaporator
fins will only be conditioned when the A/C compres-
sor is engaged and circulating refrigerant through
the A/C evaporator.
The A/C evaporator tubes are connected and sealed
to the A/C expansion valve by use of rubber O-rings
and a tapping block.
The A/C evaporator is serviced by removing and
disassembling the HVAC housing.
OPERATION
Refrigerant enters the evaporator from the expan-
sion valve as a low-temperature, low-pressure liquid.
As air flows over the fins of the evaporator, the
humidity in the air condenses on the fins, and the
heat from the air is absorbed by the refrigerant. Heat
absorption causes the refrigerant to boil and vapor-
ize. The refrigerant becomes a low-pressure gas
before it leaves the evaporator.
The evaporator cannot be repaired and, if faulty or
damaged, it must be replaced.
REMOVAL
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, impact sensor, or instrument panel com-
ponent diagnosis or service. Disconnect and isolate
the battery negative (ground) cable, then wait two
minutes for the system capacitor to discharge
before performing further diagnosis or service. This
is the only sure way to disable the supplemental
restraint system. Failure to take the proper precau-
tions could result in accidental airbag deployment.
Fig. 8 Front A/C Evaporator
1 - A/C EVAPORATOR
2 - EVAPORATOR TUBES
3 - TAPPING BLOCK
24 - 72 PLUMBINGVA

INSTALLATION
NOTE: The A/C liquid line is serviced in two sec-
tions. The front section connects between the A/C
condenser and the receiver/drier and includes the
high side service port and the A/C pressure trans-
ducer on the fitting for the receiver/drier. The rear
section connects between the receiver/drier and the
A/C expansion valve.
FRONT SECTION
(1) Position the front section of the A/C liquid line
into the engine compartment.
(2) Remove the tape or plugs from the liquid line
fitting and the receiver/drier inlet port.
(3) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(4) Connect the front section of the liquid line to
the receiver/drier.
(5) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 7 N´m
(62 in. lbs.).
(6) Position the front section of the liquid line into
the routing clip and install the routing clip onto the
body stud on the left frame rail.
(7) Install the routing clip retaining nut. Tighten
the nut to 5 N´m (45 in. lbs.).
(8) Remove the tape or plugs from the condenser
outlet port and the liquid line fitting.
(9) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the liquid line fitting.
(10) Connect the liquid line fitting to the con-
denser outlet port on the right side of the condenser.
(11) Install the nut that secures the liquid line fit-
ting to the condenser. Tighten the nut to 17 N´m (12
ft. lbs.).
(12) Reinstall the A/C pressure transducer (Refer
to 24 - HEATING & AIR CONDITIONING/CON-
TROLS/A/C PRESSURE TRANSDUCER - INSTAL-
LATION).
(13) Install the grille (Refer to 23 - BODY/EXTE-
RIOR/GRILLE - INSTALLATION).
(14) Reconnect the battery negative cable.
(15) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM EVACUATE).
(16) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM CHARGE).
REAR SECTION
(1) Position the rear section of the A/C liquid line
into the engine compartment.(2) Remove the tape or plugs from the liquid and
suction line fittings, the receiver/drier outlet port and
both expansion valve ports.
(3) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them onto the suction and
liquid line fittings for the expansion valve.
(4) Connect the liquid line and suction line fittings
to the A/C expansion valve.
(5) Install the nut that secures the suction line
and liquid line fittings to the stud on the A/C expan-
sion valve. Tighten the nut to 10 N´m (89 in. lbs.).
(6) Lubricate new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(7) Connect the liquid line fitting to the receiver/
drier outlet port.
(8) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 7 N´m
(62 in. lbs.).
(9) Install the routing clip retainer to the rear sec-
tion of the liquid line.
(10) Install the grille (Refer to 23 - BODY/EXTE-
RIOR/GRILLE - INSTALLATION).
(11) Reconnect the negative battery cable.
(12) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM EVACUATE).
(13) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM CHARGE).
RECEIVER / DRIER
DESCRIPTION
The receiver/drier is mounted in a bracket secured
to the left front strut tower in the engine compart-
ment. The receiver/drier is connected between the
front and rear sections of the A/C liquid line between
the condenser outlet and the evaporator inlet.
The receiver/drier cannot be repaired. If the receiv-
er/drier is faulty or damaged, or if the refrigerant
system has been contaminated or left open to the
atmosphere for an indeterminable period or if the
compressor has failed, it must be replaced.
OPERATION
The receiver/drier performs a filtering action to
prevent foreign material in the refrigerant from con-
taminating the A/C expansion valve. Refrigerant
enters the receiver/drier as a high-pressure, low tem-
perature liquid. Desiccant inside the receiver/drier
absorbs any moisture which may have entered and
become trapped within the refrigerant system. In
addition, during periods of high demand operation of
the A/C system, the receiver/drier acts as a reservoir
to store surplus refrigerant.
VAPLUMBING 24 - 79

all been designed with unique fittings to ensure that
an R-134a system is not accidentally contaminated
with the wrong refrigerant (R-12). There are also
labels posted in the engine compartment of the vehi-
cle and on the compressor identifying to service tech-
nicians that the air conditioning system is equipped
with R-134a.
REFRIGERANT OIL
DESCRIPTION
The refrigerant oil used in R-134a refrigerant sys-
tems is a synthetic-based, PolyAlkylene Glycol (PAG),
wax-free lubricant. Mineral-based R-12 refrigerant
oils are not compatible with PAG oils, and should
never be introduced to an R-134a refrigerant system.
There are different PAG oils available, and each
contains a different additive package. The A/C com-
pressors for this vehicle are designed to use an ND-8
PAG refrigerant oil. Use only the refrigerant oil of
this type to service the refrigerant system.
OPERATION
After performing any refrigerant recovery or recy-
cling operation, always replenish the refrigerant sys-
tem with the same amount of the recommended
refrigerant oil as was removed. Too little refrigerant
oil can cause compressor damage, and too much can
reduce air conditioning system performance.
PAG refrigerant oil is much more hygroscopic than
mineral oil, and will absorb any moisture it comes
into contact with, even moisture in the air. The PAG
oil container should always be kept tightly capped
until it is ready to be used. After use, recap the oil
container immediately to prevent moisture contami-
nation.
STANDARD PROCEDURE
REFRIGERANT OIL LEVEL
When an A/C system is assembled at the factory,
all components except the compressor are refrigerant
oil free. After the refrigerant system has been
charged and operated, the refrigerant oil in the com-
pressor is dispersed throughout the refrigerant sys-
tem. The receiver-drier, evaporator, condenser, and
compressor will each retain a significant amount of
the needed refrigerant oil.
It is important to have the correct amount of oil in
the refrigerant system. This ensures proper lubrica-
tion of the A/C compressor. Too little oil will result in
damage to the A/C compressor. Too much oil will
reduce the cooling capacity of the A/C system.
It will not be necessary to check the oil level in the
A/C compressor or to add oil, unless there has been
an oil loss. An oil loss may occur due to a rupture orleak from a refrigerant line, a connector fitting, a
component, or a component seal. If a leak occurs, add
30 milliliters (1 fluid ounce) of refrigerant oil to the
refrigerant system after the repair has been made.
Refrigerant oil loss will be evident at the leak point
by the presence of a wet, shiny surface around the
leak.
Refrigerant oil must be added when a receiver/
drier, A/C evaporator, or A/C condenser are replaced.
See the Refrigerant Oil Capacities chart. When an
A/C compressor is replaced, the refrigerant oil must
be drained from the old compressor and measured.
Drain all of the refrigerant oil from the new compres-
sor, then fill the new compressor with the same
amount of refrigerant oil that was drained out of the
old compressor.
REFRIGERANT OIL CAPACITIES
Component ml fl oz
Total A/C System Fill 410 13.9
Receiver/Drier 30 1.0
A/C Condenser 30 1.0
A/C Evaporator 60 2.0
A/C CompressorDrain and measure the oil
from the old compressor -
see text.
SUCTION LINE
REMOVAL
WARNING: Refer to the applicable warnings and
cautions for this system before performing the fol-
lowing operation (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNINGS) and (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTIONS). Failure to follow the warnings and cau-
tions could result in possible personal injury or
death.
(1) Recover the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM RECOVERY)
(2) Disconnect and isolate the negative battery
cable.
(3) Remove the routing clip retaining nut and dis-
engage the metal routing clip from the A/C suction
line.
(4) Disengage the plastic routing clip located near
the A/C expansion valve from the A/C suction line.
(5) Remove the nut that secures the A/C suction
and liquid lines to the stud on the A/C expansion
valve (Fig. 19).
VAPLUMBING 24 - 81

INDEX
ABS INDICATOR.......................8J-9ACCELERATOR PEDAL POSITION SENSOR. . . 14-32
ACCESSORY SWITCH BEZEL............23-56
ADR INDICATOR.....................8J-10
AIR CLEANER ELEMENT................9-21
AIR CLEANER HOUSING................9-21
AIR FILTER ....................24-45, 24-58
AIR OUTLET TEMPERATURE SENSOR....24-16
AIR OUTLETS.......................24-45
AIRBAG CONTROL MODULE.............8O-8
AIRBAG INDICATOR...................8J-11
ALB CONTROLLER....................5-16
ALB LEVER..........................5-16
AMBIENT TEMPERATURE INDICATOR.....8J-11
AMBIENT TEMPERATURE SENSOR.......24-17
ANTENNA BODY & CABLE..............8A-1
ARMREST..........................23-79
ASH RECEIVER......................23-57
ASH RECEIVER / CIGAR LIGHTER LAMP
UNIT..............................8L-30
ASSIST HANDLE.....................23-71
AUDIO..............................8A-1
AUTOMATIC TRANSMISSION NAG1 -
SERVICE INFORMATION................21-3
A - PILLAR TRIM.....................23-70
A / C CLUTCH RELAY.................24-24
A / C COMPRESSOR CLUTCH COIL.......24-12
A / C COMPRESSOR CLUTCH............24-8
A / C COMPRESSOR..................24-66
A / C CONDENSER COVER.............24-52
A / C CONDENSER FAN RELAY..........24-26
A / C CONDENSER HOUSING...........24-52
A / C CONDENSER....................24-69
A / C CONTROL MODULE..............24-28
A / C DISCHARGE LINE................24-71
A / C EVAPORATOR COVER.............24-55
A / C EVAPORATOR HOUSING...........24-55
A / C EVAPORATOR...................24-72
A / C EXPANSION VALVE...............24-73
A / C HEATER CONTROL...............24-12
A / C HIGH PRESSURE SWITCH.........24-30
A / C LOW PRESSURE SWITCH.........24-32
A / C PRESSURE TRANSDUCER.........24-14
BACKLITE - BULKHEAD TRIM PANEL.....23-84
BACKUP LAMP BULB..................8L-5
BASECOAT / CLEARCOAT FINISH........23-77
BATTERY CABLES....................8F-14
BATTERY HOLDDOWN.................8F-13
BATTERY SYSTEM.....................8F-1
BATTERY TRAY......................8F-16
BATTERY............................8F-6
BEARINGS - DIFFERENTIAL CASE.........3-38
BEARING / SEAL - AXLE HUB............3-28
BEARING / SEAL - AXLE................3-24
BELT TENSIONERS.....................7-5
BLOWER MOTOR RELAY...............24-33
BLOWER MOTOR RESISTOR............24-17
BLOWER MOTOR SWITCH........24-19, 24-35
BLOWER MOTOR...............24-47, 24-58
BODY...............................23-1
BOOST PRESSURE SENSOR............14-33
BRAKE INDICATOR...................8J-12
BRAKE LAMP SWITCH.................8L-6
BRAKE LINES.........................5-8
BRAKE PADS / SHOES...................5-8
BRAKE WEAR INDICATOR..............8J-13
BRAKES - ABS........................5-30
BRAKES - BASE........................5-2
BRAKE / PARK LAMP BULB.............8L-7
BULKHEAD TRIM PANEL...............23-72
BUMPERS...........................13-1
BUSHINGS............................2-3
B - PILLAR TRIM.....................23-71
CABIN HEATER.....................24-104
CABLE TENSIONER....................5-24
CABLE..............................8P-2
CABLES.............................5-24
CAMSHAFT POSITION SENSOR..........14-33
CAMSHAFT(S)........................9-28
CARGO LAMP SWITCH................8L-31
CARGO / DOME LAMP BULB............8L-30
CARGO / DOME LAMP UNIT............8L-31
CARPETS AND FLOOR MATS...........23-72
CATALYTIC CONVERTER
................11-3
CENTER BEARING
......................3-9
CENTER HIGH MOUNTED STOP LAMP BULB. . . 8L-8CENTER HIGH MOUNTED STOP LAMP UN.....8L-8
CENTER ROLLER ARM
................23-36CENTER TRACK......................23-37
CENTRAL TIMER MODULE..............8E-1
CHARGE AIR COOLER AND PLUMBING....11-4
CHARGING INDICATOR................8J-14
CHARGING SYSTEM..................8F-17
CHECK VALVE.......................8R-11
CHECK.......................23-13, 23-23
CHIME / BUZZER......................8B-1
CIGAR LIGHTER OUTLET............8W-97-1
CIRCUIT BREAKER.................8W-97-2
CLEARANCE LAMP BULB...............8L-9
CLEARANCE LAMP UNIT................8L-9
CLOCK.............................8J-14
CLOCKSPRING......................8O-12
CLUSTER BEZEL.....................23-55
COLUMN............................19-4
CONNECTOR.......................Intro.-9
CONNECTOR/GROUND/SPLICE
LOCATION........................8W-91-1
CONTROLLER ANTILOCK BRAKE.........8E-3
COOLANT LEVEL SENSOR...............7-13
COOLANT LOW INDICATOR.............8J-15
COOLANT............................7-9
COOLING.............................7-1
COWL TRIM........................23-73
CRANKCASE VENTILATION BREATHER......25-2
CRANKCASE VENTILATION HEATER.......25-1
CRANKSHAFT OIL SEAL - FRONT.........9-42
CRANKSHAFT OIL SEAL - REAR..........9-41
CRANKSHAFT POSITION SENSOR........14-35
CRANKSHAFT........................9-39
CUP HOLDER........................23-57
CYLINDER HEAD COVER(S).............9-33
CYLINDER HEAD......................9-22
DAYTIME RUNNING LAMP RELAY.......8L-10
DEFROSTER DUCTS..................24-47
DIFFERENTIAL........................3-31
DIODE............................Intro.-9
DISC BRAKE CALIPER ADAPTER.........5-14
DISC BRAKE CALIPERS.................5-11
DOME LAMP / INTRUSION SENSOR
BULB..............................8L-33
DOME LAMP / INTRUSION SENSOR......8L-33
DOME / READING LAMP BULB..........8L-32
DOME / READING LAMP UNIT..........8L-32
DOOR GLASS............23-15, 23-30, 23-46
DOOR JAMB SWITCH.................8L-34
DOOR LOCK MOTOR...................8N-1
DOOR OPENING SEALS................23-90
DOOR........................23-14, 23-23
DRIVE BELTS..........................7-5
DRIVER AIRBAG.....................8O-16
DRIVER HEATED SEAT SWITCH.........8G-11
D - PILLAR TRIM.....................23-73
ELECTRIC COOLANT PUMP.............24-75
ELECTRICAL.........................5-30
ELECTROHYDRAULIC UNIT............21-105
ENGINE BLOCK HEATER................7-14
ENGINE BLOCK.......................9-37
ENGINE CONTROL MODULE.............8E-3
ENGINE COOLANT TEMP SENSOR........7-15
ENGINE COOLANT THERMOSTAT.........7-16
ENGINE CRADLE CROSSMEMBER........13-8
ENGINE TEMPERATURE GAUGE.........8J-15
ENGINE..............................9-2
ENTRY / EXIT LAMP BULB.............8L-34
ENTRY / EXIT LAMP UNIT..............8L-35
ESP INDICATOR......................8J-16
EVAPORATOR TEMPERATURE
SENSOR......................24-19, 24-37
EXHAUST GAS RECIRCULATION..........25-4
EXHAUST MANIFOLD..................9-68
EXHAUST PIPE.......................11-3
EXHAUST SYSTEM....................11-1
EXHAUST TUBE.....................24-105
EXTERIOR HANDLE.......23-16, 23-31, 23-35
FAN DRIVE VISCOUS CLUTCH...........7-17
FASTENER IDENTIFICATION...........Intro.-3
FASTENER USAGE...................Intro.-6
FINESSE SANDING / BUFFING & POLISH . . 23-78
FLOOR DISTRIBUTION DUCTS..........24-47
FLUID AND FILTER..................21-131
FLUID CAPACITIES.....................0-5
FLUID COOLER TUBE
.................19-13
FLUID FILL / CHECK LOCATIONS
..........0-5
FLUID RESERVOIR
....................5-15
FLUID TYPES
..........................0-1
FLYWHEEL
...........................9-43FOG LAMP BULB.....................8L-10
FOG LAMP RELAY....................8L-11
FOG LAMP SWITCH...................8L-12
FRAME..............................13-3
FREEWHEELING CLUTCH.............21-135
FRONT BUMPER - STEPS...............13-2
FRONT DOOR INNER BELT
WEATHERSTRIP.....................23-90
FRONT DOOR OUTER BELT
WEATHERSTRIP.....................23-90
FRONT FASCIA.......................13-2
FRONT LAMP UNIT...................8L-13
FRONT POSITION LAMP BULB..........8L-14
FRONT SEAT BELT & RETRACTOR.......8O-20
FRONT SEAT BELT BUCKLE............8O-23
FRONT TURN / PARK / SIDE MARKER
LAMP BULB.........................8L-15
FRONT WHEEL SPEED SENSOR..........5-31
FRONT...............................2-1
FUEL DELIVERY.......................14-6
FUEL DOSING PUMP.................24-106
FUEL DRAIN TUBES..................14-10
FUEL FILL DOOR.....................23-48
FUEL FILTER CLOGGED INDICATOR......8J-17
FUEL FILTER........................14-10
FUEL GAUGE........................8J-17
FUEL INJECTOR.......................14-35
FUEL LEVEL SENDING UNIT / SENSOR....14-28
FUEL LINE.........................24-107
FUEL LINES.........................14-11
FUEL PRESSURE SENSOR.............14-39
FUEL PRESSURE SOLENOID............14-40
FUEL PUMP MODULE.................14-18
FUEL PUMP.........................14-13
FUEL QUANTITY CONTROL VALVE.......14-21
FUEL RAIL PRESSURE SENSOR.........14-12
FUEL RAIL..........................14-22
FUEL SYSTEM........................14-1
FUEL TANK.........................14-23
FUEL TEMPERATURE SENSOR..........14-42
FUSE BLOCK #1...................8W-97-2
FUSE BLOCK #2...................8W-97-3
GAP AND FLUSH.....................23-91
GEAR SELECTOR INDICATOR...........8J-18
GEAR...............................19-7
GEARSHIFT CABLE..................21-138
GEAR - PINION / RING.................3-41
GENERATOR DECOUPLER PULLEY.......8F-19
GENERATOR........................8F-18
GLOVE BOX.........................23-58
GLOW PLUG RELAY....................8I-1
GLOW PLUG..........................8I-1
GRILLE............................23-48
HCU (HYDRAULIC CONTROL UNIT).......5-36
HEADLAMP LEVELING MOTOR..........8L-16
HEADLAMP LEVELING SWITCH.........8L-17
HEADLINER.........................23-73
HEADREST..........................23-79
HEATED GLASS.......................8G-1
HEATED MIRRORS....................8G-9
HEATED SEAT ELEMENT...............8G-12
HEATED SEAT RELAY.................8G-12
HEATED SEAT SENSOR................8G-13
HEATED SEATS ......................8G-10
HEATER CORE.......................24-76
HEATER UNIT......................24-110
HEATING & AIR CONDITIONING..........24-1
HIGH BEAM HEADLAMP BULB..........8L-18
HIGH BEAM INDICATOR...............8J-19
HINGE..................23-17, 23-32, 23-51
HOISTING............................0-5
HOLDING CLUTCH B1................21-143
HOLDING CLUTCH B2................21-148
HOLDING CLUTCHES.................21-141
HOOD.............................23-51
HORN SWITCH.......................8H-1
HORN..............................8H-1
HOSES.............................19-14
HUB / BEARING........................2-4
HVAC HOUSING......................24-48
HYDRAULIC / MECHANICAL..............5-5
IGNITION CONTROL....................8I-1
INLET HOSE........................24-111
INPUT CLUTCH K1
...................21-92
INPUT CLUTCH K2
...................21-97
INPUT CLUTCH K3
..................21-102
INPUT CLUTCHES
....................21-90
INPUT SPEED SENSORS
..............21-153
VAINDEX 1
Description Group-Page Description Group-Page Description Group-Page

TABLE OF CONTENTS - Continued
BACKUP LAMP CKT SHORT TO VOLTAGE OR OPEN........................15
BACKUP LAMP SUPPLY CIRCUIT OPEN...................................16
CAN BUS CIRCUIT......................................................17
INCORRECT CAN MESSAGE FROM ABS...................................18
INTERNAL CONTROLLER................................................19
LR WHEEL SPIN CAN MESSAGE NOT VALID...............................20
OVER VOLTAGE........................................................21
RR WHEEL SPIN CAN MESSAGE NOT VALID...............................22
UNDER VOLTAGE......................................................23
TRANSMISSION - NAG1
1-2/4-5 SOLENOID CIRCUIT..............................................24
1-2/4-5 SOLENOID CIRCUIT SHORT TO GROUND...........................24
2-3 SOLENOID CIRCUIT.................................................27
2-3 SOLENOID CIRCUIT SHORT TO GROUND..............................27
3-4 SOLENOID CIRCUIT.................................................30
3-4 SOLENOID CIRCUIT SHORT TO GROUND..............................30
ABS BRAKE MESSAGE..................................................33
ABS CAN MESSAGE INCORRECT.........................................35
ABS CAN MESSAGE MISSING............................................36
ABS LF SENSOR MESSAGE..............................................38
ABS LR SENSOR MESSAGE.............................................40
ABS RF SENSOR MESSAGE.............................................42
ABS RR SENSOR MESSAGE.............................................44
ACCEL PEDAL SENSOR CAN MESSAGE INCORRECT.......................46
CAN BUS CIRCUIT......................................................48
CAN MESSAGE FROM ECM FROM SLA....................................53
CONTROL MODULE TCM IS NOT CODED..................................55
ENGINE CAN MESSAGE INCORRECT.....................................56
ENGINE CAN MESSAGE MISSING........................................58
ENGINE OVERSPEED...................................................60
ENGINE RPM MESSAGE.................................................62
ENGINE TEMP MESSAGE................................................64
ENGINE TORQUE MESSAGE INCORRECT.................................66
ENGINE TORQUE REDUCTION...........................................68
IC CAN MESSAGE INCORRECT..........................................70
IC/ATC CAN MESSAGE MISSING..........................................72
IMPROPER GEAR......................................................74
IMPROPER RATIO......................................................76
INPUT SENSOR MISMATCH..............................................78
INPUT SENSOR OVERSPEED............................................80
INTERNAL CONTROLLER................................................82
INVALID CONTROL MODULE VERSION....................................83
MODULATING PRESSURE SOLENOID CIRCUIT.............................84
N2 INPUT SPEED SENSOR CIRCUIT......................................87
N3 INPUT SPEED SENSOR CIRCUIT......................................91
SENSOR SUPPLY VOLTAGE..............................................95
SHIFT LEVER POSITION INVALID.........................................97
SHIFT PRESSURE SOLENOID CIRCUIT....................................99
SLA CAN MESSAGE INCORRECT........................................102
SOLENOID SUPPLY VOLTAGE...........................................103
SOLENOID SUPPLY/WATCHDOG.........................................105
SYSTEM OVERVOLTAGE...............................................107
ii

1.0 INTRODUCTION
The procedures contained in this manual include
all of the specifications, instructions, and graphics
needed to diagnose NAG1 Electronic Automatic
Transmission and Shift Lever Assembly problems.
The diagnostics in this manual are based on the
failure condition or symptom being present at the
time of diagnosis.
When repairs are required, refer to the appropri-
ate volume of the service information for the proper
removal and repair procedure.
READ THIS MANUAL BEFORE TRYING TO
DIAGNOSE A VEHICLE TROUBLE CODE.
Diagnostic procedures change every year. New
diagnostic systems may be added and/or carryover
systems may be enhanced. It is recommended that
you review the entire manual to become familiar
with all new and changed diagnostic procedures.
1.1 SYSTEM COVERAGE
This diagnostic procedures manual covers all
Sprinter (VA) equipped with a NAG1 Automatic
Transmission.
1.2 SIX -STEP TROUBLESHOOTING
PROCEDURE
Diagnosis of the NAG1 electronic transmission is
done in six basic steps:
Verification of complaint
Verification of any related symptoms
Symptom analysis
Problem isolation
Repair of isolated problem
Verification of proper operation
2.0 IDENTIFICATION OF
SYSTEM
The NAG1 Transmission family can be identified
by the presence of a 13 pin electrical connector, with
a bayonet lock on the right hand side of the trans-
mission. The connector is oriented horizontally.
3.0 SYSTEM DESCRIPTION AND
FUNCTIONAL OPERATION
3.1 GENERAL DESCRIPTION
The NAG1 electronic transmission is an electron-
ically controlled five speed transmission with a
controlled slip torque converter. The NAG1 elec-tronic transmission is a conventional transmission
in that it uses hydraulically applied clutches to shift
a planetary gear train. However, the electronic
control system replaces many of the mechanical and
hydraulic components used in conventional trans-
mission valve bodies.
The ratios for the gear stages are obtained by 3
planetary gear sets. Fifth Gear is designed as an
Overdrive with a high speed ratio. The gears are
actuated electronically/hydraulically. The electronic
control system enables precise adaptation of pres-
sures to the respective operating conditions and to
the engine output during a shift phase, which
results in a significant improvement in shift qual-
ity.
3.2 FUNCTIONAL OPERATION
The NAG1 electronic transmission has a fully
adaptive control system. The system performs its
functions based on continuous real-time sensor and
switch feedback information. In addition the TCM
receives information from the Shift Lever Assembly,
ECM (engine management) and ABS (chassis sys-
tems) controllers over the CAN bus. The CAN bus is
a high speed communication bus that allows real
time control capability between various controllers.
Most messages are sent every 20 milliseconds, this
means critical information can be shared between
the Transmission, Shifter, Engine and ABS control-
lers. The CAN bus is a two wire bus with aCAN C
Bus (+) circuitand aCAN C Bus (-) circuit. The
CAN bus uses a twisted pair of wires in the harness
to reduce the potential of radio and noise interfer-
ence. The CAN bus also uses a 120 ohm terminating
resistor in both the ECM and Sentry Key Remote
Entry Module (SKREEM) modules. The module
terminating resistance is measured across both
CAN bus circuits at the ECM or SKREEM module.
The control system automatically adapts to
changes in engine performance, vehicle speed, and
transmission temperature variations to provide
consistent shift quality. The control system ensures
that clutch operation during upshifting and down-
shifting is more responsive without increased
harshness. The TCM controls the actuation of sole-
noid valves for modulating shift pressure and gear
change. The required pressure level is calculated
from the load condition, engine speed. Power for the
transmission system is supplied through the Trans-
mission Relay. The TCM is located in the under the
drivers seat of the vehicle.
The Transmission Control Module (TCM) contin-
uously checks for electrical problems, mechanical
problems, and some hydraulic problems. When a
problem is sensed, the TCM stores a diagnostic
trouble code (DTC). Some of these codes cause the
transmission to go into9limp-in9or9default9mode.
1
GENERAL INFORMATION