2006 MERCEDES-BENZ SPRINTER tow

(3) Check the brake system for any leaks.
(4) Reconnect the electrical connector to the brake
fluid level indicator (Fig. 14).
ALB LEVER
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the retaining clip for the ALB lever
(Fig. 15).
(3) Remove the bolt for the lever at the axle (Fig.
15).
(4) Remove the lever.
INSTALLATION
(1) Install the lever to the vehicle.
(2) Install the lower mounting bolt to the axle (Fig.
15).
(3) Install the lever to the shock bolt and then
install the clip (Fig. 15).
(4) Check the side deflection of the ALB lever with
a straight edge from Point-A to Point-B as the
graphic shows. Max deflection play of the actuator
rod should be no more than 15 mm (.60 in) (Fig. 15).
(5) Lower the vehicle.
ALB CONTROLLER
REMOVAL
(1) Install the brake pedal rod to hold the brake
pressure.
(2) Raise and support the vehicle.(3) Remove the brake lines to the (automatic load-
dependant brake pressure control) ALB controller.
(4) Remove the adjusting nut and the spring from
the ALB controller.
(5) Remove the mounting bolts.
(6) Remove the ALB controller.
INSTALLATION
(1) Install the ALB controller to the vehicle.
(2) Install the mounting bolts for the controller.
(3) Install the brake lines. Tighten the lines to 16
N´m (142 in. lbs.)
(4) Install the adjusting rod, nut and spring to the
ALB controller.
(5) Lower the vehicle.
(6) Remove the brake pedal hold down rod.
(7) Fill and bleed the brake system (Refer to 5 -
BRAKES - STANDARD PROCEDURE).
(8) Raise the vehicle and adjust the ALB controller
(Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/
ALB CONTROLLER - ADJUSTMENTS).
(9) Lower the vehicle and test drive.
ADJUSTMENTS
ADJUSTMENT
(1) Clean any debris away from the test ports caps
at the ALB controller.
(2) Connect brake adapters special tool 9297 to the
test ports at the ALB controller.
(3) Install a Pressure Gauge, Special Tool
C-4007-A, to the adapters.
(4) Tighten all tube nut fittings to 17 N´m (145 in.
lbs.) torque.
(5) Bleed any air out of the system. This includes
bleeding the air from the hose between the pressure
test fitting and pressure gauge, which is done at the
pressure gauge.
NOTE: Adjustment is determined for the automatic
load-dependent brake power control system accord-
ing to the ALB plate. This is housed in the stowage
compartment under the front passenger's door
panel. The part number of the rear spring is
stamped into the spring eye. This must correspond
to the part number of the rear spring on the ALB
plate.
(6) To accurately adjust the rear axle load you
must first determine the rear axle load by weighing
the vehicle at a local scale.
(7) Install the brake pedal winch Special tool 9296
between the brake pedal and the driver seat and
slowly turn the dial until the specified inlet brake
pressure is indicated at the gauge.
Fig. 15 ALB LEVER DEFLECTION
1 - CLIP
2 - SPRING
3 - LEVER
4 - STRIAGHT EDGE
5 - NUT
6 - POINT -A
7 - POINT - B
8 - SUSPENSION POINT
5 - 16 BRAKES - BASEVA

COOLING
TABLE OF CONTENTS
page page
COOLING
OPERATION - COOLING SYSTEM...........1
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - PRELIMINARY
CHECKS.............................1COOLING SYSTEM.....................2
ACCESSORY DRIVE.......................5
ENGINE.................................9
COOLING
OPERATION - COOLING SYSTEM
The cooling system regulates engine operating tem-
perature. It allows the engine to reach normal oper-
ating temperature as quickly as possible. It also
maintains normal operating temperature and pre-
vents overheating.
The cooling system also provides a means of heat-
ing the passenger compartment and cooling the auto-
matic transmission fluid (if equipped). The cooling
system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - PRELIMINARY
CHECKS
ENGINE COOLING SYSTEM OVERHEATING
Establish what driving conditions caused the com-
plaint. Abnormal loads on the cooling system such as
the following may be the cause:
²PROLONGED IDLE
²VERY HIGH AMBIENT TEMPERATURE
²SLIGHT TAIL WIND AT IDLE
²SLOW TRAFFIC
²TRAFFIC JAMS
²HIGH SPEED OR STEEP GRADES
Driving techniques that avoid overheating are:
²Idle with A/C off when temperature gauge is at
end of normal range.²Increasing engine speed for more air flow is rec-
ommended.
TRAILER TOWING:
Consult Trailer Towing section of owners manual.
Do not exceed limits.
AIR CONDITIONING; ADD - ON OR AFTER MARKET:
A maximum cooling package should have been
ordered with vehicle if add-on or after market A/C is
installed. If not, maximum cooling system compo-
nents should be installed for model involved per
manufacturer's specifications.
RECENT SERVICE OR ACCIDENT REPAIR:
Determine if any recent service has been per-
formed on vehicle that may effect cooling system.
This may be:
²Engine adjustments (incorrect timing)
²Slipping engine accessory drive belt(s)
²Brakes (possibly dragging)
²Changed parts. Incorrect water pump or pump
rotating in wrong direction due to belt not correctly
routed
²Reconditioned radiator or cooling system refill-
ing (possibly under filled or air trapped in system).
NOTE: If investigation reveals none of the previous
items as a cause for an engine overheating com-
plaint, (Refer to 7 - COOLING - DIAGNOSIS AND
TESTING)
VACOOLING 7 - 1

HEATED SYSTEMS
TABLE OF CONTENTS
page page
HEATED GLASS........................... 1
HEATED MIRRORS......................... 9HEATED SEATS........................... 10
HEATED GLASS
TABLE OF CONTENTS
page page
HEATED GLASS
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING
ELECTRIC BACKLIGHT (EBL) SYSTEM.....2
REAR WINDOW DEFOGGER RELAY
DESCRIPTION..........................3
OPERATION............................3
REMOVAL.............................4
INSTALLATION..........................4REAR WINDOW DEFOGGER SWITCH
DESCRIPTION..........................4
OPERATION............................4
DIAGNOSIS AND TESTING
REAR WINDOW DEFOGGER SWITCH......5
REMOVAL.............................6
INSTALLATION..........................6
REAR WINDOW DEFOGGER GRID
STANDARD PROCEDURE
GRID LINE AND TERMINAL REPAIR........7
HEATED GLASS
DESCRIPTION
CAUTION: Grid lines can be damaged or scraped
off with sharp instruments. Care should be taken in
cleaning glass or removing foreign materials,
decals or stickers. Normal glass cleaning solvents
or hot water used with rags or toweling is recom-
mended.
The rear window defogger system, also known as
the electric backlight (EBL), consists of a backglass
with two vertical bus bars linked by a series of grid
lines fired onto the inside surface of the rear window.
The EBL system is turned On or Off by a control
switch (Fig. 1) located in the instrument panel near
the right side of the steering wheel, which sends a
request signal to the rear window defogger module
that operates the left and right rear window defogger
relays located in the fuse/relay block under the driv-
ers seat.
Circuit protection is provided by a 30 amp fuse
also located in the fuse/relay block.
OPERATION
When the rear window defogger switch is pressed
to the On position, current is directed through the
switch to the rear window defogger module. The rear
window defogger module then grounds the control
side of the left and right rear window defogger (EBL)
Fig. 1 Rear Window Defogger Switch
1 - REAR WINDOW DEFOGGER SWITCH
2 - INSTRUMENT PANEL
VAHEATED SYSTEMS 8G - 1

The heated seat system components operate on
battery current received through a fuse in the Fuse
Block on a fused ignition switch output (run-acc) cir-
cuit so that the system will only operate when the
ignition switch is in the On or Accessory positions.
The heated seat system will be turned Off automati-
cally whenever the ignition switch is turned to any
position except On or Accessory. Also, the heated seat
system will not operate when the surface tempera-
ture of the seat cushion cover at either heated seat
sensor is above the designed temperature set points
of the system.DIAGNOSIS AND TESTING - HEATED SEATS
Refer toWiringfor the appropriate wiring infor-
mation. The wiring information includes wiring dia-
grams, proper wire and connector repair procedures,
further details on wire harness routing and reten-
tion, as well as pin-out and location views for the
various wire harness connectors, splices and grounds.
HEATED SEAT SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO HEATED SEAT SWITCH
ILLUMINATION WITH IGNI-
TION ON1. Faulty fuse. 1. Check heated seat fuse in Fuse Block. Re-
place fuse, if required.
2. Wiring faulty. 2. Check fused ignition switch output (run-acc)
circuit from heated seat switch connector to igni-
tion switch. Repair, if required.
3. Ground faulty. 3. Check for ground at heated seat switch con-
nector. Repair, if required.
4. Faulty switch. 4. Refer to Heated Seat Switch for the proper
switch diagnosis and testing procedures.
DRIVER HEATED SEAT
SWITCH
DESCRIPTION
The heated seat switches are located on the instru-
ment panel, in the accessory switch bezel. The two,
momentary rocker type switches provide a signal to
the Heated Seat Relay through separate hard wired
circuits. Each switch contains two light emitting
diodes (LED), one for each High and Low setting to
let the occupant know that the seat heater system is
on.
The heated seat switches and their LED's cannot
be repaired. If either switch is faulty or damaged the
entire switch must be replaced.
OPERATION
There are three modes that can be selected with
each of the heated seat switches: Off, Low, and High.
When the top of the switch rocker is depressed, the
low mode is selected and the low mode LED indicator
illuminates. Depressing the top of the switch rocker a
second time will turn the heated seat to Off. This
same process is repeated for High heat setting. The
heated seats will automatically return to the Off
mode anytime the vehicle ignition switch is turned
Off.Both switches provide separate hard wire inputs to
the Heated Seat Relay to indicate the selected mode.
The Heated Seat Relay responds to the heated seat
switch messages by controlling the output to the seat
heater elements of the selected seat.
DIAGNOSIS AND TESTING - DRIVER HEATED
SEAT SWITCH
For circuit description and diagrams, refer toWir-
ing.
(1) Inspect the Heated Seat Switches for apparent
damage or sticking/binding and replace if required.
Refer to Heated Seat Switch Removal and Installa-
tion in this section.
(2) Replace the heated seat switch with a known
good unit and retest the heated seat system.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the gear selector bezel trim. Refer to
the Body section for the procedure.
(3) Remove the storage bin. Refer to the Body sec-
tion for the procedure.
(4) Remove the switch bezel retaining screw and
remove the switch bezel from the instrument panel.
Refer to the Body section for the procedure.
(5) Disconnect electrical connections.
VAHEATED SEATS 8G - 11

(6) Working from the underside of the switch, gen-
tly rock the switch back and forth out of its mounting
location in the switch bezel.
INSTALLATION
(1) Install the heated seat switch in its mounting
location in the switch bezel.
(2) Connect electrical connections.
(3) Position the switch bezel and install the retain-
ing screw. Refer to the Body section for the proce-
dure.
(4) Install the storage bin. Refer to the Body sec-
tion for the procedure.
(5) Install the gear selector bezel trim. Refer to the
Body section for the procedure.
(6) Connect the negative battery cable.
HEATED SEAT ELEMENT
DESCRIPTION
The heated seat system includes two seat heating
elements in each front seat, one for the seat cushion
(Fig. 1) and the other for the seat back. All models
use two resistor wire heating elements for each seat
that are connected in series with the Heated Seat
Relay. The temperature sensor is a Negative Temper-
ature Coefficient (NTC) thermistor. One temperature
sensor is used for each seat, and it is located in the
seat cushion heating element for all models.The seat heating elements are glued onto the seat
and seat back cushions. The heated seat elements
and the temperature sensor cannot be adjusted or
repaired and, if faulty or damaged a new seat assem-
bly must be installed.
OPERATION
The heated seat elements resist the flow of electri-
cal current. When battery current is passed through
the elements, the energy lost by the resistance of the
elements is released in the form of heat. The heated
seat temperature sensor is a NTC thermistor. When
the temperature of the seat cushion cover rises, the
resistance of the sensor decreases. The heated seat
relay uses this temperature sensor input to monitor
the temperature of the seat, and regulates the cur-
rent flow to the seat heating elements accordingly.
DIAGNOSIS AND TESTING - HEATED SEAT
ELEMENT
For complete circuit diagrams, refer toWiring.
NOTE: When checking heated seat elements for
continuity, be certain to move the heating element
being checked. Moving the element, such as sitting
in the seat will eliminate the possibility of an inter-
mittent open in the element which would only be
evident if the element was in a certain position.
Failure to check the element in various positions
could result in an incomplete test.
(1) Disconnect and isolate the battery negative
cable. Disconnect the heated seat element wire har-
ness connector from under the seat cushion. Check
for continuity between the seat heater driver circuit
and ground. There should be continuity, less than 7
ohms. If OK, go to Step 2. If not OK, replace the seat
assembly.
(2) Check for continuity between the seat heater
B+ driver circuit cavity and the seat back frame.
There should benocontinuity. If OK, heating ele-
ment is OK at this time. If not OK, replace the seat
assembly.
HEATED SEAT RELAY
DESCRIPTION
The heated seat relay is an electromechanical
device that switches 12v battery current to the
heated seat elements when the relay control coil is
energized. The heated seat relay is located in the
Fuse Block, under the drivers seat. The heated seat
relay is a International Standards Organization
(ISO) relay. Relays conforming to the ISO specifica-
tions have common physical dimensions, current
capacities, terminal patterns, and terminal functions.
Fig. 1 Heated Seat Element - Typical
1 - Seat Back Wire Harness
2 - Heated Seat Wire Harness Connector
3 - Heated Seat Cushion Element
8G - 12 HEATED SEATSVA

The heated seat relay cannot be repaired or
adjusted and, if faulty or damaged, it must be
replaced.
OPERATION
The ISO relay consists of an electromagnetic coil, a
resistor or diode, and three (two fixed and one mov-
able) electrical contacts. The movable (common feed)
relay contact is held against one of the fixed contacts
(normally closed) by spring pressure. When the elec-
tromagnetic coil is energized, it draws the movable
contact away from the normally closed fixed contact,
and holds it against the other (normally open) fixed
contact. When the electromagnetic coil is de-ener-
gized, spring pressure returns the movable contact to
the normally closed position. The resistor or diode is
connected in parallel with the electromagnetic coil in
the relay, and helps to dissipate voltage spikes that
are produced when the coil is de-energized.
DIAGNOSIS AND TESTING - HEATED SEAT
RELAY
The heated seat relay is located in the Fuse Block,
under the drivers seat. Refer toWiringfor the loca-
tion of complete heated seat system wiring diagrams.
(1) Remove the heated seat relay from the fuse
block.
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   5 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.
(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, check the relay supply circuits. If not
OK, replace the faulty relay.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) The heated seat relay is located in the fuse
block, under the drivers seat. Refer to wiring for
detailed location.
(3) Grasp the heated seat relay firmly and pull it
straight out from the fuse block. A slight rocking
motion will aid in removal.
INSTALLATION
(1) Grasp the heated seat relay firmly and push it
straight in the fuse block.
(2) Reconnect the battery negative cable.
HEATED SEAT SENSOR
DESCRIPTION
The heated seat temperature sensor is a Negative
Temperature Coefficient (NTC) thermistor. One tem-
perature sensor is used for each seat. The sensor is
located in the seat cushion heating element for all
models.
The heated seat sensor cannot be adjusted or
repaired and if it is found to be faulty, the complete
heated seat element must be replaced.
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR
For complete circuit diagrams, refer toWiring.
NOTE: Any resistance values (ohmsV) given in the
following text are supplied using the automatic
range generated by a FLUKETautomotive meter. If
another type of measuring device is used the val-
ues generated may not be the same as the results
shown here, or may have to be converted to the
range used here.
(1) Backprobe the heated seat relay wire harness
connector, do not disconnect. Using an voltmeter,
check the voltage of the seat temperature sensor
input cavity of the heated seat relay wire harness
connector. The seat sensor input voltage should be
between 1.7 volts and 3.0 volts with the system ON.
If OK, sensor is OK at this time. If not OK, replace
the faulty seat cushion heating element and sensor
assembly.
PASSENGER HEATED SEAT
SWITCH
DESCRIPTION
The heated seat switches are located on the instru-
ment panel, in the accessory switch bezel. The two,
momentary rocker type switches provide a signal to
the Heated Seat Relay through separate hard wired
circuits. Each switch contains two light emitting
diodes (LED), one for each High and Low setting to
let the occupant know that the seat heater system is
on.
The heated seat switches and their LED's cannot
be repaired. If either switch is faulty or damaged the
entire switch must be replaced.
OPERATION
There are three modes that can be selected with
each of the heated seat switches: Off, Low, and High.
When the top of the switch rocker is depressed, the
low mode is selected and the low mode LED indicator
illuminates. Depressing the top of the switch rocker a
VAHEATED SEATS 8G - 13

second time will turn the heated seat to Off. This
same process is repeated for High heat setting. The
heated seats will automatically return to the Off
mode anytime the vehicle ignition switch is turned
Off.
Both switches provide separate hard wire inputs to
the Heated Seat Relay to indicate the selected mode.
The Heated Seat Relay responds to the heated seat
switch messages by controlling the output to the seat
heater elements of the selected seat.
DIAGNOSIS AND TESTING - PASSENGER
HEATED SEAT SWITCH
For circuit description and diagrams, refer toWir-
ing.
(1) Inspect the Heated Seat Switches for apparent
damage or sticking/binding and replace if required.
Refer to Heated Seat Switch Removal and Installa-
tion in this section.
(2) Replace the heated seat switch with a known
good unit and retest the heated seat system.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the gear selector bezel trim. Refer to
the Body section for the procedure.
(3) Remove the storage bin. Refer to the Body sec-
tion for the procedure.
(4) Remove the switch bezel retaining screw and
remove the switch bezel from the instrument panel.
Refer to the Body section for the procedure.
(5) Disconnect electrical connections.
(6) Working from the underside of the switch, gen-
tly rock the switch back and forth out of its mounting
location in the switch bezel.
INSTALLATION
(1) Install the heated seat switch in its mounting
location in the switch bezel.
(2) Connect electrical connections.
(3) Position the switch bezel and install the retain-
ing screw. Refer to the Body section for the proce-
dure.
(4) Install the storage bin. Refer to the Body sec-
tion for the procedure.
(5) Install the gear selector bezel trim. Refer to the
Body section for the procedure.
(6) Connect the negative battery cable.
8G - 14 HEATED SEATSVA

REAR TURN LAMP BULB
REMOVAL.............................23
INSTALLATION.........................23
REPEATER LAMP BULB
REMOVAL.............................23
INSTALLATION.........................24
REPEATER LAMP UNIT
REMOVAL.............................24INSTALLATION.........................25
TAIL LAMP UNIT
REMOVAL.............................25
INSTALLATION.........................26
TURN SIGNAL RELAY
REMOVAL.............................26
INSTALLATION.........................26
LAMPS / LIGHTING - EXTE-
RIOR
DESCRIPTION
The exterior lighting system for this model
includes the following exterior lamps:
²Backup Lamps- The backup (or reverse) lamps
are integral to the tail lamp units mounted to the
back of the quarter panel on each side of the tailgate
at the rear of the vehicle.
²Brake Lamps- The brake (or stop) lamps
include a bulb and reflector that are integral to the
tail lamp units mounted to the back of the quarter
panel on each side of the tailgate opening, and the
Center High Mounted Stop Lamp (CHMSL) that is
centered on the rear edge of the roof panel above the
tailgate opening.
²Daytime Running Lamps- Vehicles manufac-
tured for sale in Canada have a Daytime Running
Lamps (DRL) relay that illuminates the low beam
headlamp bulbs whenever the engine is running.
²Fog Lamps- Fog lamp bulbs and reflectors are
included in both front lamp units of vehicles
equipped with this option.
²Hazard Warning Lamps- The hazard warning
lamps include all of the right and left turn signal and
repeater lamps.
²Headlamps- Separate low beam and high
beam headlamp bulbs are installed in the front lamp
unit on each side of the front grille opening. A head-
lamp leveling actuator motor is also integral to each
front lamp unit.
²Park Lamps- The park lamps include the front
park/side marker lamps and front position lamps
that are integral to the front lamp units mounted on
either side of the front grille opening, as well as the
rear park lamps and rear side marker lamps that are
integral to the tail lamp units mounted to the back of
the quarter panel on each side of the tailgate open-
ing. Included in the park lamps circuit are two rear
license plate lamp units mounted on the left rear
tailgate door. The park lamps may also include
optional clearance lamps, which are located on each
side of a vehicle that is so equipped.
²Turn Signal Lamps- The turn signal lamps
include the front turn lamps that are integral to the
front lamp units, the rear turn lamps that are inte-
gral to the tail lamp units, and a repeater lampmounted to each front fender just above the front
wheel opening.
Other components of the exterior lighting system
for this model include:
²Brake Lamp Switch- A plunger-type brake
lamp switch is located on the steering column sup-
port bracket under the instrument panel and actu-
ated by the brake pedal arm.
²Daytime Running Lamp Relays- Vehicles
manufactured for sale in Canada have two Daytime
Running Lamps (DRL) relays. Dedicated right and
left side relays illuminate the low beam headlamp
bulb installed in each front lamp unit whenever the
engine is running. These relays are located in dedi-
cated vehicle wire harness connectors within the
driver side front seat riser.
²Fog Lamp Relay- Vehicles equipped with the
optional fog lamps have a fog lamp relay located in a
dedicated vehicle wire harness connector within the
driver side front seat riser.
²Fog Lamp Switch- A fog lamp switch is
mounted in the instrument cluster bezel, below the
cluster and outboard of the steering column on vehi-
cles equipped with this option.
²Headlamp Leveling Motor- A headlamp lev-
eling actuator motor is located on the back of each
headlamp housing and adjusts both the low beam
headlamp, high beam headlamp, and fog lamp (if
equipped) reflector frames in unison.
²Headlamp Leveling Switch- A thumbwheel
actuated headlamp leveling switch is mounted in the
instrument cluster bezel, below the cluster and out-
board of the steering column.
²Multi-Function Switch- The multi-function
switch is located on the top of the steering column,
just below the steering wheel. The multi-function
switch is connected directly to the fuse block located
below the steering column through an integral inter-
face connector. Only the left (lighting), right (wiper)
control stalks and the hazard warning switch button
for the multi-function switch are visible, the remain-
der of the switch is concealed beneath the steering
column shrouds. The multi-function switch includes a
left (lighting) control stalk and a right (wiper) control
stalk. The left control stalk is dedicated to providing
almost all of the driver controls for the exterior light-
ing system.
²Trailer Tow Connector- Vehicles equipped
with a factory-approved, field-installed trailer towing
8L - 2 LAMPS/LIGHTING - EXTERIORVA