2006 MERCEDES-BENZ SPRINTER seats

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

HEATED SEATS
TABLE OF CONTENTS
page page
HEATED SEATS
DESCRIPTION.........................10
OPERATION...........................10
DIAGNOSIS AND TESTING - HEATED SEATS . 11
DRIVER HEATED SEAT SWITCH
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING - DRIVER HEATED
SEAT SWITCH........................11
REMOVAL.............................11
INSTALLATION.........................12
HEATED SEAT ELEMENT
DESCRIPTION.........................12
OPERATION...........................12
DIAGNOSIS AND TESTING - HEATED SEAT
ELEMENT...........................12
HEATED SEAT RELAY
DESCRIPTION.........................12OPERATION...........................13
DIAGNOSIS AND TESTING - HEATED SEAT
RELAY..............................13
REMOVAL.............................13
INSTALLATION.........................13
HEATED SEAT SENSOR
DESCRIPTION.........................13
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR............................13
PASSENGER HEATED SEAT SWITCH
DESCRIPTION.........................13
OPERATION...........................13
DIAGNOSIS AND TESTING - PASSENGER
HEATED SEAT SWITCH.................14
REMOVAL.............................14
INSTALLATION.........................14
HEATED SEATS
DESCRIPTION
Individually controlled, electrically heated front
seats are available factory-installed optional equip-
ment on this model. Vehicles with this option can be
visually identified by the two separate heated seat
switches mounted in the instrument panel. The
heated seat system allows the front seat driver and
passenger to select from two different levels of sup-
plemental electrical seat heating, or no seat heating
to suit their individual comfort requirements. The
heated seat system for this vehicle includes the fol-
lowing major components, which are described in fur-
ther detail later in this section:
²Heated Seat Elements- Four heated seat ele-
ments are used per vehicle, two for each front seat.
One heating element in the seat back and one in the
seat cushion. The heated seat sensor is integral to
the seat cushion heating element. The heated seat
elements are integral to the front seat and seat back
cushions. Refer to heated seat elements later in this
section for additional information.
²Heated Seat Relay- One heated seat relay is
used per vehicle. The relay is located in the fuse
block and is responsible for distributing the voltage
(B+) to the heated seat elements.
²Heated Seat Sensors- Two heated seat sen-
sors are used per vehicle, one for each front seat. The
heated seat sensors are integral to each of the heatedseat element assemblies. Refer to heated seat sensor
later in this section for additional information.
²Heated Seat Switches- Two heated seat
switches are used per vehicle, one for each front seat.
The switches are mounted in the instrument panel.
Refer to heated seat switches later in this section for
additional information.
Hard wired circuitry connects the heated seat sys-
tem components to each other through the electrical
system of the vehicle. Refer to Wiring for additional
information. The wiring information includes wiring
diagrams, proper wire and connector repair proce-
dures, further details on wire harness routing and
retention, as well as pin-out and location views for
the various wire harness connectors, splices and
grounds.
OPERATION
The heated seat system is designed to provide indi-
vidually controlled, supplemental heat to the seat
cushion and seat back surfaces of both front seats.
Because this system converts electrical current to
heat, the heated seat system can provide a measure
of warm comfort almost immediately upon entering a
cold vehicle, rather than having to wait for the
engine coolant to reach sufficient temperature to
deliver heat through the conventional heater system.
This system allows each front seat occupant to indi-
vidually select one of two comfort levels, Hi or Lo, or
to turn the heater for their seat off.
8G - 10 HEATED SEATSVA

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

(5) Remove the pin and the two turning loops from
the turning loop bracket.
(6) For a left outboard seating position only,
unsnap and remove the plastic cover from the screw
that secures the rear seat belt lower anchor to the
left outboard side of the seat frame (Fig. 33).
(7) Remove the plastic shield from the back of the
rear seat. (Refer to 23 - BODY/SEATS/REAR SEAT
BACK SHIELD - REMOVAL).
(8) Remove the screw that secures the rear seat
belt lower anchor to the rear seat cushion frame (Fig.
33) or (Fig. 34).(9) Pull the rear seat belt and lower anchor
through the turning loop trim cover and the turning
loop bracket.
(10) Remove the screw that secures the rear seat
belt retractor to the bracket on the rear seat cushion
frame (Fig. 35).
(11) Remove the rear seat belt and retractor unit
from the bracket on the rear seat cushion frame.
Fig. 32 Rear Seat Belt Turning Loop
1 - TURNING LOOP (2)
2 - PUSH NUT
3 - BRACKET
4 - PIN
5 - REAR SEAT BACK
6 - SEAT BELT
Fig. 33 Left Outboard Rear Seat Belt Lower Anchor
1 - REAR SEAT CUSHION TRIM
2 - REAR SEAT BACK TRIM
3 - SCREW AND COVER
4 - REAR SEAT BELT LOWER ANCHOR
Fig. 34 Right Outboard or Center Rear Seat Belt
Lower Anchor
1 - REAR SEAT CUSHION FRAME
2 - SCREW
3 - REAR SEAT BELT LOWER ANCHOR
Fig. 35 Rear Seat Belt Retractor
1 - RETRACTOR
2 - REAR SEAT CUSHION FRAME
3 - SCREW
VARESTRAINTS 8O - 29

INSTALLATION
WARNING: To avoid personal injury or death, during
and following any seat belt service, carefully
inspect all seat belts, buckles, mounting hardware,
retractors, and anchors for proper installation, oper-
ation, or damage. Replace any belt that is cut,
frayed, or torn. Straighten any belt that is twisted.
Tighten any loose fasteners. Replace any belt that
has a damaged or inoperative buckle or retractor.
Replace any belt that has a bent or damaged latch
plate or anchor plate. Never attempt to repair a seat
belt component. Always replace damaged or faulty
seat belt components with the correct, new and
unused replacement parts listed in the
DaimlerChrysler Mopar Parts Catalog.
(1) Position the rear seat belt and retractor unit
onto the bracket of the rear seat cushion frame (Fig.
35). Be certain to engage the guide on the retractor
into the locating notch on the bracket.
(2) Install and tighten the screw that secures the
rear seat belt retractor to the bracket on the rear
seat cushion frame. Tighten the screw to 35 N´m (26
ft. lbs.).
(3) Route the rear seat belt and lower anchor
through the turning loop bracket and the turning
loop trim cover.
(4) Position the rear seat belt lower anchor to the
rear seat cushion frame (Fig. 33) or (Fig. 34).
(5) Install and tighten the screw that secures the
rear seat belt lower anchor to the rear seat cushion
frame. Tighten the screw to 35 N´m (26 ft. lbs.).
(6) For a left outboard seating position only, rein-
stall the plastic cover onto the screw that secures the
rear seat belt lower anchor to the left outboard side
of the seat frame.
(7) Position the two seat belt turning loops to the
turning loop bracket so that one turning loop is
located behind the bracket and one is located in front
of the bracket (Fig. 32).
(8) From the front of the turning loop bracket,
insert the pin through both turning loops and the
bracket, then secure it from behind the bracket with
a new push nut.
(9) Position the turning loop trim cover over the
turning loop bracket.
(10) Lift the seat belt webbing to access and install
the plastic push pin fastener that secures the rear
seat belt turning loop trim cover to the turning loop
bracket at the top of the seat back (Fig. 31).
(11) Reinstall the plastic shield onto the back of
the rear seat. (Refer to 23 - BODY/SEATS/REAR
SEAT BACK SHIELD - INSTALLATION).
(12) Reinstall the rear bench seat into the vehicle.
REAR SEAT BELT BUCKLE
REMOVAL
REMOVAL - INBOARD
WARNING: To avoid personal injury or death, during
and following any seat belt service, carefully
inspect all seat belts, buckles, mounting hardware,
retractors, and anchors for proper installation, oper-
ation, or damage. Replace any belt that is cut,
frayed, or torn. Straighten any belt that is twisted.
Tighten any loose fasteners. Replace any belt that
has a damaged or inoperative buckle or retractor.
Replace any belt that has a bent or damaged latch
plate or anchor plate. Never attempt to repair a seat
belt component. Always replace damaged or faulty
seat belt components with the correct, new and
unused replacement parts listed in the
DaimlerChrysler Mopar Parts Catalog.
(1) Remove the rear bench seat containing the
inboard rear seat belt buckle unit to be serviced from
the vehicle.
(2) Remove the plastic shield from the back of the
rear seat. (Refer to 23 - BODY/SEATS/REAR SEAT
BACK SHIELD - REMOVAL).
(3) Remove the screw that secures either the
inboard rear seat belt buckle to the rear seat cushion
frame (Fig. 36).
(4) Remove the inboard rear seat belt buckle from
the rear seat cushion frame.
Fig. 36 Inboard Rear Seat Belt Buckle
1 - REAR SEAT CUSHION FRAME
2 - INBOARD REAR SEAT BELT LOWER ANCHOR
3 - SCREW
4 - INBOARD REAR SEAT BELT BUCKLE
8O - 30 RESTRAINTSVA