2006 MERCEDES-BENZ SPRINTER heating

IGNITION CONTROL
TABLE OF CONTENTS
page page
IGNITION CONTROL
OPERATION - GLOW PLUG................1
SPECIAL TOOLS........................1
GLOW PLUG
REMOVAL.............................1
INSTALLATION..........................1GLOW PLUG RELAY
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING - GLOW PLUG
RELAYS..............................2
IGNITION CONTROL
OPERATION - GLOW PLUG
Pre - Glowing
With the key in the On position, the glow plug out-
put stage and the indicator lamp are actuated by the
ECM. The pre-heating time is calculated by the ECM
in line with the coolant temperature. The glow plug
output stage switches the current through the glow
plugs. The glow plug indicator lamp goes out after a
pre-glow period has elapsed. Component or cable fail-
ures in the pre-glow system are indicated by the glow
plug lamp and stored in the ECM.
Glow Output Stage
With the ignition key in the On position a signal is
transmitted from the ECM to the glow plug output
stager. If no data is exchanged with the ECM the
glow plug stage is terminated after two seconds. The
glow plug out put stage constantly signals the cur-
rent operating state (ON/OFF) and any system
faults. The following faults are recognized by the out
put stage and transmitted to the ECM:
²Open circuit in one or more of the glow plug
leads
²Short circuit in the glow plug circuit
²Out put stage fault or temperature related shut-
off
If a failure in the glow plug system occurs, the
glow plug indicator lamp will be illuminated only as
long as the fault is current. If the failure is no longer
present, the glow plug indicator lamp will be
switched off but a code will be stored in the ECM.
After Glow
Once the engine has started, the ECM determines
the after glow time depending on cooling tempera-
ture. During this time the glow plugs continue to be
actuated by the glow plug output stage. This results
in improved smooth running after a cold start and
improved warming up properties, elimination of blueexhaust after a cold start up and a more stable cold
starting speed.
If no signal is received from the coolant tempera-
ture sensor the signal from the oil sensor is used as a
substitute.
SPECIAL TOOLS
GLOW PLUG
REMOVAL
(1) Disconnect the negative battery cable.
(2) Remove the engine cover.
(3) Use special tool #9286 pliers to unplug the
glow plug wiring harness connector(s) at the glow
plug.
(4) Remove the glow plug(s) (Fig. 1).
INSTALLATION
(1) Screw glow plug(s) into cylinder head and
tighten to 12 N´m (115 lbs. in) (Fig. 1).
(2) Connect the glow plug wiring harness connec-
tor(s)
(3) Install the engine cover.
(4) Connect negative battery cable.
GLOW PLUG RELAY
DESCRIPTION
The glow plug relay supplies battery voltage to the
glow plug through a timed cycle that is related to
coolant temperature. The glow plug relay is located
under the battery. The purpose of a glow plug system
GLOW PLUG PLIERS
VAIGNITION CONTROL 8I - 1

is to improve combustion for low emissions and to
achieve easy starting at low temperatures.
OPERATION
When the ignition key is turned to the ON posi-
tion, the glow plug output stage and pre-glow indica-
tor lamp are actuated by the ECM. The duration of
the signal depends on the coolant temperature. The
glow plug relay has processing that communicates
with the ECM. If no data exchange occurs at the trig-
gering stage, the preheating is switched off after 2
seconds.
Start glowing is initiated when the key is in the
start position. The glow plugs (R13±R17) continue to
be supplied with voltage. This makes it possible to
stabilize the cold starting speed. (After glowing is ini-
tiated when the starter reject speed is reached).
After the engine starts, the ECM determines the
afterglow period in line with coolant temperature. If
no signal is received from the coolant temperature
sensor, afterglow is maintained for thirty seconds.
The following aims are reached by the afterglow :
²Improvement in warming-up properties
²Prevention of white exhaust smoke after cold
start
²Stabilizing of the cold starting speed
The glow plug output stage constantly signals the
current operating state and faults. The following are
faults detected and transmitted to the ECM :²Open circuit at one or several glow plugs
²Short circuit in the glow plug circuit
²Relay fault
If the Glow plug relay detects an open circuit at a
glow plug, it is stored and indicated only once the
engine is running by the preglow indicator lamp com-
ing on for about one minute and a fault is stored in
the ECM. If a short circuit, a glow plug output stage
faulty or a temperature related switching off of out-
put stages is detected, the fault is stored and indi-
cated immediately by the preglow indicator lamp
coming on. Once the fault is no longer current, the
indicator is immediately switched off, but the fault is
stored in the ECM. If the fault is constantly current,
the preglow indicator lamp remains on until the igni-
tion is switched off.
DIAGNOSIS AND TESTING - GLOW PLUG
RELAYS
Refer to the appropriate Diesel Powertrain Diagno-
sis Manual for information on diagnosing the glow
plug relays.
Fig. 1 GLOW PLUG (S)
1 - GLOW PLUG
2 - WIRING HARNESS CONNECTOR3 - INTAKE MANIFOLD
4 - ENGINE COVER
8I - 2 IGNITION CONTROLVA

8W-97 POWER DISTRIBUTION
TABLE OF CONTENTS
page page
POWER DISTRIBUTION
DESCRIPTION..........................1
OPERATION............................1
CIGAR LIGHTER OUTLET
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING - CIGAR LIGHTER
OUTLET.............................2
REMOVAL.............................2
CIRCUIT BREAKER
DESCRIPTION..........................2
OPERATION............................2
DIAGNOSIS AND TESTING - CIRCUIT
BREAKER............................2
FUSE BLOCK #1
DESCRIPTION..........................2
OPERATION............................3
REMOVAL.............................3
INSTALLATION..........................3FUSE BLOCK #2
DESCRIPTION..........................3
OPERATION............................3
POWER DISTRIBUTION CENTER
DESCRIPTION..........................3
OPERATION............................3
POWER OUTLET
DESCRIPTION..........................3
OPERATION............................4
DIAGNOSIS AND TESTING - POWER OUTLET . 4
REMOVAL.............................4
INSTALLATION..........................4
RELAY
DESCRIPTION..........................4
OPERATION............................5
DIAGNOSIS AND TESTING - RELAY.........5
REMOVAL.............................5
INSTALLATION..........................5
POWER DISTRIBUTION
DESCRIPTION
This section describes the power distribution com-
ponents used on this model as well as the methods in
which battery voltage and charging system voltage is
distributed throughout the vehicle. The power distri-
bution system for this vehicle consists of the follow-
ing major components which are covered in further
detail later in this section:
²Fuseblock #1
²Fuseblock #2
²Power Distribution Center (PDC)
The power distribution system also incorporates
various types of circuit control and protection fea-
tures, including:
²Automatic resetting circuit breakers
²Blade-type fuses
²Cartridge fuses
²Relays
Following are general descriptions and theory of
operation for the major components in the power dis-
tribution system. Refer to Wiring for the location of
complete circuit diagrams for the various power dis-
tribution system components.
OPERATION
The power distribution system for this vehicle is
designed to provide safe, reliable, and centralized dis-
tribution points for the electrical current required to
operate all of the standard and optional factory-in-
stalled electrical and powertrain, chassis, safety,
security and convenience systems. At the same time,
the power distribution system was designed to pro-
vide easy access to these electrical distribution points
for the vehicle technician to use when conducting
diagnosis and repair of faulty circuits. The power dis-
tribution system can also prove useful for the addi-
tion of electrical circuits that may be required to
operate accessories that the vehicle owner may
choose to have installed in the aftermarket.
CIGAR LIGHTER OUTLET
DESCRIPTION
The cigar lighter outlet is installed in the instru-
ment panel, near the center of the instrument panel.
The cigar lighter outlet is secured by a snap fit
within the instrument panel.
The cigar lighter knob/heating element, and the
cigar lighter outlet are available for service. These
components cannot be repaired and, if faulty or dam-
aged, they must be replaced.
VA8W-97 POWER DISTRIBUTION 8W - 97 - 1

OPERATION
The cigar lighter consists of two major components:
a knob and heating element unit, and the cigar
lighter base or receptacle shell. The receptacle shell
is connected to ground, and an insulated contact in
the bottom of the shell is connected to battery cur-
rent. The cigar lighter receives battery voltage from a
fuse in the fuseblock only when the ignition switch is
in the Accessory or On positions.
The knob and heating element are encased within
a spring-loaded housing, which also features a sliding
protective heat shield. When the heating element is
inserted in the receptacle shell, the heating element
resistor coil is grounded through its housing to the
receptacle shell. If the cigar lighter knob is pushed
inward, the heat shield slides up toward the knob
exposing the heating element.
Two small spring-clip retainers are located on
either side of the insulated contact inside the bottom
of the receptacle shell. These clips engage and hold
the heating element against the insulated contact
long enough for the resistor coil to heat up and glow.
When the resistor coil becomes sufficiently heated,
excess heat radiates from the heating element caus-
ing the spring-clips to expand. Once the spring-clips
expand far enough to release the heating element,
the spring-loaded housing forces the knob and heat-
ing element to pop back outward to their relaxed
position. When the cigar lighter knob and element
are pulled out of the receptacle shell, the protective
heat shield slides downward on the housing so that
the heating element is recessed and shielded around
its circumference for safety.
DIAGNOSIS AND TESTING - CIGAR LIGHTER
OUTLET
For cigar lighter outlet diagnosis and testing pro-
cedures (Refer to 8 - ELECTRICAL/POWER DISTRI-
BUTION/POWER OUTLET - DIAGNOSIS AND
TESTING)
REMOVAL
For cigar lighter outlet removal procedure (Refer to
8 - ELECTRICAL/POWER DISTRIBUTION/POWER
OUTLET - REMOVAL).
CIRCUIT BREAKER
DESCRIPTION
Automatic resetting circuit breakers are used to
protect the power window voltage supply circuits.
These circuit breakers can protect the systems from a
short circuit, or from an overload condition caused byan obstructed or stuck power window regulator or
switch.
The circuit breaker cannot be repaired and, if
faulty or damaged, it must be replaced.
OPERATION
The circuit breaker contains a bi-metal strip sand-
wiched between two contacts forming the connection
in the circuit. An overload condition causes the
bi-metal strip to heat and bend to the open position,
disconnecting current flow to the circuit. Then as the
system overload or short circuit is removed, the
bi-metal strip cools, re-establishing contact to allow
current flow to the circuit.
DIAGNOSIS AND TESTING - CIRCUIT BREAKER
For complete circuit descriptions and diagrams,
refer toWiring.
(1) Locate the correct circuit breaker in the fuse-
block. Pull out the circuit breaker slightly, but be cer-
tain that the circuit breaker terminals still contact
the terminals in the fuseblock cavities.
(2) Connect the negative lead of a 12-volt DC volt-
meter to a good ground.
(3) With the voltmeter positive lead, check both
terminals of the circuit breaker for battery voltage.
If only one terminal has battery voltage, the circuit
breaker is faulty and must be replaced. If neither ter-
minal has battery voltage, repair the open circuit
from the Power Distribution Center as required.
FUSE BLOCK #1
DESCRIPTION
An electrical fuse block is concealed under the
driver side steering column. The fuse block serves to
distribute electrical current to many of the electrical
systems in the vehicle. The fuse block contains blade-
type mini fuses, relays and micro processors that
enable automatic control of some of the power distri-
bution circuits throughout the vehicle.
The molded plastic fuse block housing has an inte-
gral mounting bracket that is secured with screws to
the steering column. A finger recess is molded into
the cover for easy removal. A fuse layout map is
molded onto the back side of the cover to ensure
proper fuse identification.
The fuse block cannot be repaired, if the fuse block
is faulty or damaged or if any internal circuit is
faulty or damaged, the entire fuse block must be
replaced.
8W - 97 - 2 8W-97 POWER DISTRIBUTIONVA

OPERATION
All of the circuits entering and leaving the fuse
block do so through the instrument panel wire har-
ness. Internal connection of all of the fuse block cir-
cuits is accomplished by an intricate combination of
hard wiring and bus bars. Internal relays and micro
processors allow the vehicle electronics to control
some of the power distribution circuits throughout
the vehicle. Refer to the Wiring section for complete
circuit diagrams.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove fuse block cover by rotating locking
screw 90É.
(3) Remove the steering column cover. Refer to the
Body section for the procedure.
(4) Unscrew fuse block connections and disconnect
all electrical connectors from the fuse block.
(5) Remove the fuse block from the steering col-
umn.
INSTALLATION
(1) Position the fuse block in the steering column.
(2) Install fuse block connections and connect all
electrical connectors on the fuse block.
(3) Install the steering column cover. Refer to the
Body section for the procedure.
(4) Install fuse block cover by rotating locking
screw 90É.
(5) Connect the negative battery cable.
(6) Set time and radio stations.
FUSE BLOCK #2
DESCRIPTION
An electrical fuse block is concealed under the
driver side front seat. The fuse block serves to dis-
tribute electrical current to many of the electrical
systems in the vehicle. The fuse block houses blade-
type mini fuses, blade-type automatic resetting cir-
cuit breakers and International Standards
Organization relays. Additional provisions are avail-
able in the fuse block for additional fuses and ISO
relays.
The molded plastic fuse block housing has an inte-
gral mounting bracket that is secured with screws to
the seat base. The driver side seat base also has a
snap-fit fuse access panel that can be removed for
service of the fuses and the relays. A finger recess is
molded into one end for easy removal. A fuse layout
map is molded onto the back side of the panel to
ensure proper fuse identification.
The fuse block is integral to the body wire harness.
If any internal circuit or the fuse block housing isfaulty or damaged, the entire fuse block and body
wire harness unit must be replaced.
OPERATION
All of the circuits entering and leaving the fuse
block do so through the body wire harness. Internal
connection of all of the fuse block circuits is accom-
plished by an intricate combination of hard wiring
and bus bars.
POWER DISTRIBUTION CEN-
TER
DESCRIPTION
All of the electrical current distributed throughout
this vehicle is directed through the Power Distribu-
tion Center (PDC). The molded plastic PDC housing
is located in the left front corner of the engine com-
partment, on the battery positive cable. The PDC
housing has a molded plastic cover that slides over
the PDC housing. The PDC cover is easily opened or
removed for service access.
The PDC unit cannot be repaired and is only ser-
viced as a unit with the headlamp and dash wire
harness. If the internal circuits or the PDC housing
are faulty or damaged, the headlamp and dash wire
harness unit must be replaced.
OPERATION
All of the current from the battery and the gener-
ator output enters the PDC through the positive bat-
tery cable. The PDC cover is removed to access the
battery and generator output connection B(+) termi-
nal studs. Internal connection of all of the PDC cir-
cuits is accomplished by an intricate combination of
hard wiring and bus bars. Refer to Wiring Diagrams
for the location of complete PDC circuit diagrams.
POWER OUTLET
DESCRIPTION
The power outlet is installed in the instrument
panel accessory switch plate, which is located near
the center of the instrument panel. The power outlet
base is secured by a snap fit within the instrument
panel. A plastic protective cap snaps over the power
outlet base when the power outlet is not being used.
While the power outlet is very similar to a cigar
lighter base unit, it does not include the two small
spring-clip retainers inside the bottom of the recepta-
cle shell that are used to secure the cigar lighter
heating element to the insulated contact.
The power outlet receptacle unit are available for
service. The power outlet receptacle cannot be
VA8W-97 POWER DISTRIBUTION 8W - 97 - 3

REMOVAL
WARNING: NO SPARKS, OPEN FLAMES OR SMOK-
ING. RISK OF POISONING FROM INHALING AND
SWALLOWING FUEL. RISK OF INJURY TO EYES
AND SKIN FROM CONTACT WITH FUEL. POUR
FUELS ONLY INTO SUITABLE AND APPROPRI-
ATELY MARKED CONTAINERS. WEAR PROTECTIVE
CLOTHING.
WARNING: RISK OF INJURY TO SKIN AND EYES
FROM SCALDING WITH HOT COOLANT. RISK OF
POISONING FROM SWALLOWING COOLANT. DO
NOT OPEN COOLING SYSTEM UNLESS COOLANT
TEMPERATURE IS BELOW 90ÉC (194ÉF). OPEN CAP
SLOWLY TO RELEASE PRESSURE. STORE COOL-
ANT IN SUITABLE AND APPROPRIATELY MARKED
CONTAINER. WEAR PROTECTIVE GLOVES,
CLOTHES, AND EYE WEAR.
(1) Disconnect the negative battery cable.
NOTE: REPLACE THE AIR CONDITIONING DRIER
WHEN EVER THE AIR CONDITIONING SYSTEM IS
OPENED.
(2) Drain cooling system (Refer to 7 - COOLING/
ENGINE/COOLANT - STANDARD PROCEDURE).
(3) Evacuate and recover air conditioning system
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - STANDARD PROCEDURE).
(4) Remove the front grille and fascia assembly.(5) Disconnect the engine wiring harness at the
cabin side and carefully guide though the cowl into
the engine area.
Fig. 2 ENGINE COVER
1 - ENGINE COVER
2 - FASTENERS
VAENGINE 9 - 5

(6) Remove the turbocharger heat shield (Fig. 3).
(7) Remove the engine cover (Fig. 3).
(8) Remove the air cleaner and hose at the turbo-
charger and air cleaner assembly.
(9) Disconnect the transmission lines at the radia-
tor.
(10) Disconnect the upper and lower radiator
hoses.
(11) Disconnect the A/C lines at the condenser.
(12) Disconnect the condenser fan harness connec-
tor.
(13) Disconnect the power steering cooler lines at
the cooler.
(14) Disconnect the charge air cooler hose at the
intake manifold (Fig. 3).
(15) Remove charge air hose fasteners at the radi-
ator closure panel.
(16) Remove the fasteners retaining the radiator to
the front crossmember.(17) Remove the change air cooler, A/C conderser
and fan as an assembly.
(18) Disconnect the charge air hose at the intake
manifold (Fig. 3).
(19) Remove the radiator assembly.
(20) Disconnect the high pressure and return
hoses at the power steering pump.
(21) Disconnect the fuel lines at the fuel filter.
(22) Disconnect the refrigerant line at the A/C
compressor.
(23) Disconnect the vacuum line for the brake
booster at the vacuum pump (Fig. 3).
(24) Disconnect the coolant hose of heating return
flow at the water pump.
(25) Disconnect the coolant hose of the heater sup-
ply at the coolant pipe at the side of the cylinder
head.
Fig. 3 ENGINE COVER
1 - ENGINE COVER 6 - HIGH PRESSURE FUEL PUMP
2 - FUEL RAIL 7 - VACUUM PUMP
3 - INTAKE MANIFOLD 8 - OIL LEVEL INDICATOR
4 - EGR VALVE 9 - HEAT SHIELD
5 - AIR INLET TUBE 10 - TRANSMISSION OIL LEVEL INDICATOR
9 - 6 ENGINEVA

(11) Install the torque converter access plate. Refer
to (Refer to 21 - TRANSMISSION/TRANSAXLE/AU-
TOMATIC - NAG1 - INSTALLATION) for correct
sequence and torque specification.
(12) Install the transmission cooler lines to trans-
mission. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - NAG1 - INSTALLATION) for
correct sequence and torque specification.
(13) Connect the engine valley drain hose to the
transmission (Fig. 5).
(14) Install transmission electrical connector and
shifter hardware. Refer to (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - NAG1 - INSTAL-
LATION) for correct sequence and torque
specification.
(15) Install the steering gear and tighten in two
stages. 25 N´m (18.5 lbs. ft.), then 45 N´m (33 lbs. ft.)
plus 90É.
(16) Install the starter.
(17) Connect the ground strap (left side).
(18) Align and install the exhaust and bracket
(Refer to 11 - EXHAUST SYSTEM/EXHAUST PIPE -
INSTALLATION).
(19) Lower the vehicle.
(20) Install the lower heater housing and filter.
(21) Install the air inlet hose, CCV breather and
CCV heater at the turbocharger (Fig. 4).
(22) Connect the coolant supply and return hoses.
(23) Connect the brake booster vacuum hose at the
vacuum pump.(24) Connect the fuel lines at the filter assembly
(Fig. 9).
(25) Connect the power steering hoses.
(26) Install the radiator/charge air cooler and
hose(s) assemblies (Refer to 7 - COOLING/ENGINE/
RADIATOR - INSTALLATION).
(27) Install A/C condenser and fan assemblies Con-
nect the fan harness connector.
(28) Connect the refrigerant lines.
(29) Install a air conditioning receiver/drier (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING/RECEIVER / DRIER - INSTALLATION).
(30) Connect the upper and lower radiator hoses.
(31) Connect the transmission lines at the radia-
tor.
(32) Install air cleaner housing and connect the air
inlet duct and air flow sensor.
(33) Connect the charge air cooler hose at intake
manifold. (Refer to 9 - ENGINE/AIR INTAKE SYS-
TEM/AIR CLEANER HOUSING - INSTALLATION).
(34) Route the engine wiring harness inside the
vehicle and connect.
(35) Install the turbocharger heat shield.
(36) Install the front grille and fascia assembly.
(37) Connect the negative battery cable.
(38) Check and fill engine oil (Refer to LUBRICA-
TION & MAINTENANCE/FLUID TYPES - SPECIFI-
CATIONS).
Fig. 8 CRANKSHAFT POSITION SENSOR
1 - ENGINE BLOCK
2 - WIRING HARNESS CONNECTOR
3 - CRANKSHAFT POSITION SENSOR
4 - STARTER SOLENOID
Fig. 9 FUEL FILTER
1 - FUEL SUPPLY FROM TANK
2 - FUEL SUPPLY TO HIGH PRESSURE PUMP
3 - POWER STEERING RESERVOIR
4 - FUEL FILTER
5 - OIL FILTER
6 - WATER IN FUEL SENSOR
9 - 10 ENGINEVA