2006 MERCEDES-BENZ SPRINTER mirror

3.2.2 CAN BUS
The CAN bus (controller area network) is a data
bus system specifically design for inter module
communication on this vehicle. The CAN bus con-
sists of a special twisted two-core cable. Control
modules are connected to this9twisted pair9. The
CAN bus incorporates two terminating resistors.
One terminator is built into the Engine Control
Module (ECM) and the other is built into the Sentry
Key Remote Entry Module (SKREEM). Each resis-
tor has a value of 120 ohms. The resistor condition
can be confirmed by disconnecting the control mod-
ule and measuring the resistance value at the
appropriate control module pins. This measure-
ment should read 120 ohms. The two CAN circuits,
CAN C Bus (+) and CAN C Bus (-), are bridged by
these two terminating resistors when all control
modules are connected to the bus. These two resis-
tors are connected to the CAN bus network in
parallel. The measurement between the two
twisted CAN circuits, with both the ECM and
SKREEM connected, should measure a value of 60
ohms.
The CAN bus is bi-directional. This means that
each connected control module can send and receive
information. Transmission of data takes place re-
dundantly via both circuits. The data bus levels are
mirrored, meaning that if the binary level on one
circuit is 0, the other circuit transmits binary level
1 and vice versa. The two line concept is used for
two reasons: for fault identification and as a safety
concept.
If a voltage peak occurs on just one circuit, the
receivers can identify this as a fault and ignore the
voltage peak. If a short circuit or interruption
occurs on one of the two CAN circuits, a software-
hardware linked safety concept allows switching to
a single-line operation. The defective CAN circuit is
shut down. A specific data protocol controls how and
when the participants can send and receive.
NOTE: It is important to note the CAN Bus
circuits are used for inter-module
communication only, and is no way
connected to the K-Lines.
The following modules that use the CAN Bus on
this vehicle are:
²Automatic Temperature Control (ATC)
²Controller Antilock Brake (CAB)
²Engine Control Module (ECM)
²Instrument Cluster (IC)
²Sentry Key Remote Entry Module (SKREEM)
²Shifter Assembly (SA)
²Transmission Control Module (TCM)
3.3 HEATING & A/C SYSTEM
3.3.1 AUTOMATIC TEMPERATURE
CONTROL (ATC)
3.3.1.1 SYSTEM CONTROLS
The ATC Module:
²is fully addressable with the DRBIIIt.
IThe DRBIIItcommunicates with the ATC
Module through the Diagnostic Link Connector
(DLC) via a K-Line.
²communicates with other modules over the Con-
troller Area Network (CAN) C Bus.
²controls A/C clutch operation.
²controls EBL operation.
²controls water cycle valve operation.
IThe water cycle valve is a normally open valve,
meaning that it allows full engine coolant flow
through the heater core when no power is
delivered to the valve. The ATC controls the
valve with a pulse width signal. The lower the
percentage of the pulse width signal the more
the valve is open.
²controls Residual Heat Utilization (REST) func-
tion.
²controls blower motor operation, providing four
blower speeds (Low, M1, M2, & High).
²controls recirculation air solenoid valve.
²controls the mode door via cables.
²controls the main power supply to the Heater
Booster (if equipped).
²uses air inlet temperature sensor, air outlet tem-
perature sensor, and evaporator temperature
sensor input, as well as data from other modules
to maintain occupant comfort levels.
3.3.1.2 SYSTEM DIAGNOSTICS
Fault detection is through active and stored Diag-
nostic Trouble Codes (DTCs)
²DTCs are displayed by the DRBIIIt.
²Active DTCs are those which currently exist in
the system. The condition causing the fault must
be repaired in order to clear this type of DTC.
²Stored DTCs are those which occurred in the
system since the ATC Module received the last
9clear diagnostic info9message.
Testing Preparation & Diagnostics
Set the necessary system functions accordingly so
that all of the following prerequisites are met prior
to performing diagnostic tests on the ATC system:
5
GENERAL INFORMATION

WARNING:REASSEMBLE ALL COMPONENTS
BEFORE ROAD TESTING A VEHICLE. DO NOT
TRY TO READ THE DRBIIITSCREEN OR
OTHER TEST EQUIPMENT DURING A TEST
DRIVE. DO NOT HANG THE DRBIIITOR OTHER
TEST EQUIPMENT FROM THE REARVIEW
MIRROR DURING A TEST DRIVE. HAVE AN
ASSISTANT AVAILABLE TO OPERATE THE
DRBIIITOR OTHER TEST EQUIPMENT.
FAILURE TO FOLLOW THESE INSTRUCTIONS
CAN RESULT IN PERSONAL INJURY OR
DEATH.
5.0 REQUIRED TOOLS AND
EQUIPMENT
DRBIIIt(diagnostic read-out box)
Jumper wires
Ohmmeter
Voltmeter
Test Light
8310 Airbag System Load Tool
8443 SRS Airbag System Load Tool
9001 R F Detector
6.0 GLOSSARY OF TERMS
ABSantilock brake system
ACMairbag control module
ACTactuator
AECMairbag electronic control module
(ACM)
ASDMairbag system diagnostic module
(ACM)
AT Cautomatic temperature control
CABcontroller antilock bake
CANcontroller area network
CHMcabin heater module
CPAconnector positive assurance
CTMcentral timer module
DABdriver airbag
DCHAdiesel cabin heater assist (cabin
heater)
DLCdata link connector
DTCdiagnostic trouble code
DRdriver
EBLelectric back lite (rear window de
fogger)
ECMengine control module
GCCGulf Coast Countries
HBMheater booster module
HVACheater ventilation, air conditioning
ICinstrument cluster
MICmechanical instrument cluster
RSMRain Sensor Module
SAshifter assembly
SKREEMsentry key remote entry module
SSMsecurity system module
TCMtransmission control module
13
GENERAL INFORMATION

Symptom:
CHECKING THE RAIN SENSOR/WIPER OPERATION
POSSIBLE CAUSES
CHECK THE WIPER MOTOR CIRCUIT CAVITY 2
CHECK THE WIPER MOTOR CIRCUIT CAVITY 5
CHECK THE WIPER MOTOR CIRCUIT CAVITY 5 II
CHECK THE WIPER MOTOR CIRCUIT CAVITY 6
CHECK THE WIPER MOTOR CIRCUIT CAVITY 6 II
CHECK WIPER MOTOR GROUND CIRCUIT
CHECKING THE 12 VOLT POWER SUPPLY
CHECKING THE GROUND CIRCUIT
CHECKING THE RAIN SENSOR OPERATION
CHECKING WIPER SIGNALS TO THE RAIN SENSOR MODULE
RAIN SENSOR
RAIN SENSOR CIRCUIT(S) OPEN
RAIN SENSOR CIRCUIT(S) SHORTED TO GROUND
RAIN SENSOR CIRCUIT(S) SHORTED TO VOLTAGE
RAIN SENSOR MODULE
RAIN SNSR CKTS SHORTED TOGETHER
WIPER MOTOR
TEST ACTION APPLICABILITY
1 Turn the ignition on.
Monitor the windshield wipers while turning the wiper switch to each of the 4 switch
positions: OFF, INTERMITTENT, LOW and HIGH.
Did the wipers functions properly in each wiper switch position?All
Ye s!Go To 2
No!Go To 8
2NOTE: The Rain Sensor is located in the windshield mount of the rear view
mirror in the top-center of the windshield.
NOTE: The Rain Sensor Module (RSM) is mounted above the accelerator
pedal assembly.
Turn the ignition on.
Move the Wiper Switch to the Intermittent position.
Spray or pour water on the Rain Sensor area of the windshield.
Did the wipers activate when water was sprayed/poured on the Rain Sensor area of
the windshield?All
Ye s!Rain Sensor/Wiper System operating properly. Test complete.
No!Go To 3
239
WINDSHIELD WIPER & WASHER

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the Rain Sensor Module harness connector.
Measure the resistance between ground and each of the Rain Sensor circuits at the
Rain Sensor Module harness connector.
Is the resistance above 1000 ohms for each measurement?All
Ye s!Go To 4
No!Repair the circuit(s) that measured below 1000 ohms for a short to
ground.
4 Turn the ignition off.
Disconnect the Rain Sensor Module harness connector.
Turn the ignition on.
Measure the voltage of each of the Rain Sensor circuits at the Rain Sensor Module
harness connector.
Is the voltage below 1.0 volt for each measurement?All
Ye s!Go To 5
No!Repair the circuit(s) that measured above 1.0 volt for a short to
voltage.
5 Turn the ignition off.
Disconnect the Rain Sensor harness connector.
Disconnect the Rain Sensor Module harness connector.
Measure the resistance of each Rain Sensor circuit between the Rain Sensor Module
harness connector and the Rain Sensor harness connector.
Is the resistance below 10.0 ohms for each measurement?All
Ye s!Go To 6
No!Repair the circuit(s) that measured above 10.0 ohms for an open.
6 Turn the ignition off.
Disconnect the Rain Sensor harness connector.
Disconnect the Rain Sensor Module harness connector.
Measure the resistance between Rain Sensor harness connector cavities 1 and 2.
Repeat this step for cavities 1 and 3, cavities 2 and 3.
Is the resistance above 1000 ohms for each measurement?All
Ye s!Go To 7
No!Repair the circuit(s) that measured below 1000 ohms for a short
together.
7 Turn the ignition off.
Replace the Rain Sensor in accordance with the Service Information.
Turn the ignition on.
Move the Wiper Switch to the Intermittent position.
Spray or pour water on the Rain Sensor area of the windshield.
NOTE: The Rain Sensor is located in the windshield mount of the rear view
mirror in the top-center of the windshield.
Did the wipers activate when water was sprayed/poured on the Rain Sensor area of
the windshield?All
Ye s!Replace the original Rain Sensor in accordance with the Service
Information.
No!Replace the Rain Sensor Module in accordance with the Service
Information.
240
WINDSHIELD WIPER & WASHER
CHECKING THE RAIN SENSOR/WIPER OPERATION ÐContinued

4.2.4 DRBIIITSAFETY INFORMATION
WARNING: EXCEEDING THE LIMITS OF THE
DRBIIITMULTIMETER IS DANGEROUS. IT
CAN EXPOSE YOU TO SERIOUS OR
POSSIBLE FATAL INJURY. CAREFULLY
READ AND UNDERSTAND THE CAUTIONS
AND THE SPECIFICATION LIMITS.
²Follow the vehicle manufacturer 's service speci-
fications at all times.
²Do not use the DRBIIItif it has been damaged.
²Do not use the test leads if the insulation is
damaged or if metal is exposed.
²To avoid electrical shock, do not touch the test
leads, tips, or the circuit being tested.
²Choose the proper range and function for the
measurement. Do not try voltage or current mea-
surements that may exceed the rated capacity.
²Do not exceed the limits shown in the table below:
FUNCTION INPUT LIMIT
Volts 0 - 500 peak volts AC
0 - 500 volts DC
Ohms (resistance)* 0 - 1.12 megaohms
Frequency Measured
Frequency Generated0-10kHz
Temperature -58 - +1100ÉF
-50 - +600ÉC
* Ohms cannot be measured if voltage is present.
Ohms can be measured only in a non-powered
circuit.
± Voltage between any terminal and ground
must not exceed 500v DC or 500v peak AC.
± Use caution when measuring voltage above
25v DC or 25v AC.
± Use the low current shunt to measure circuits
up to 10A. Use the high current clamp to
measure circuits exceeding 10A.
± When testing for the presence of voltage or
current, make sure the meter is functioning
correctly. Take a reading of a known voltage or
current before accepting a zero reading.
± When measuring current, connect the meter in
series with test load.
± When using the meter function, keep the
DRBIIItaway from spark plug or coil wires to
avoid measuring error from outside interfer-
ence.
4.3 WARNING
4.3.1 VEHICLE DAMAGE WARNINGS
Before disconnecting any control module, make
sure the ignition is ``off ''. Failure to do so could
damage the module.
When testing voltage or continuity at any control
module, use the terminal side (not the wire end) of
the connector. Do not probe a wire through the
insulation; this will damage it and eventually cause
it to fail because of corrosion.
Be careful when performing electrical tests so as
to prevent accidental shorting of terminals. Such
mistakes can damage fuses or components. Also, a
second code could be set, making diagnosis of the
original problem more difficult.
4.3.2 ROAD TESTING A COMPLAINT
VEHICLE
Some complaints will require a test drive as part
of the repair verification procedure. The purpose of
the test drive is to try to duplicate the diagnostic
code or symptom condition.
CAUTION: Before road testing a vehicle, be
sure that all components are reassembled.
During the test drive, do not try to read the
DRBIIITscreen while in motion. Do not hang
the DRBIIITfrom the rear view mirror or
operate it yourself. Have an assistant
available to operate the DRBIIIT.
4.4 DIAGNOSIS
1. Your diagnostic test procedure must begin with a
thorough visual inspection of the system in ques-
tion for damaged components or disconnected
connectors. For ABS, the brake lamps must be
operational prior to continuing.
2. Connect the DRBIIItto the data link connector
located under the dash. If the DRBIIItdoes not
power up, check the power and ground supplies
to the connector.
3. Select the system in question. Turn the ignition
on. If the DRBIIItdisplays ``No Responseº, refer
to Communication in the Body Diagnostic Pro-
cedures manual to diagnose the symptom.
4. Read and record all diagnostic trouble codes. If
any additional codes are present, proceed to the
appropriate test.
5. For ABS, if there are no diagnostic trouble codes
present, select ``Inputs/Outputs'' and read the
Brake Switch and Brake Lamp Switch inputs as
you press and release the brake pedal. If the
6
GENERAL INFORMATION

service manual. Following these procedures is very
important to the safety of the individuals perform-
ing the diagnostic tests.
4.2.2 VEHICLE PREPARATION FOR
TESTING
Make sure the vehicle being tested has a fully
charged battery. If it does not, false diagnostic codes
or error messages may occur.
4.2.3 SERVICING SUB-ASSEMBLIES
Some components of the powertrain system are
intended to be serviced as an assembly only. At-
tempting to remove or repair certain system sub-
components may result in personal injury and/or
improper system operation. Only those components
with approved repair and installation procedures in
the service manual should be serviced.
4.2.4 DRBIIITSAFETY INFORMATION
WARNING: EXCEEDING THE LIMITS OF THE
DRBIIITMULTIMETER IS DANGEROUS. IT
CAN EXPOSE YOU TO SERIOUS OR
POSSIBLE FATAL INJURY. CAREFULLY
READ AND UNDERSTAND THE CAUTIONS
AND SPECIFICATION LIMITS.
Follow the vehicle manufacturer 's service specifi-
cations at all times.
± Do not use the DRBIIItif it has been dam-
aged.
± Do not use the test leads if the insulation is
damaged or if metal is exposed.
± To avoid electrical shock, do not touch the test
leads, tip or the circuit being tested.
± Choose the proper range and function for the
measurement. Do not try voltage or current
measurements that may exceed the rated ca-
pacity.
± Do not exceed the limits shown in the table
below:
FUNCTION INPUT LIMIT
Volts 0±500 peak volts AC
0±500 volts DC
Ohms (Resistance)* 0±1.12 megaohms
Frequency Measure
Frequency Generated0±10 kHz
Temperature ±58 ± +1100ÉF
±50 ± +600ÉC
* Ohms cannot be measured if voltage is present.
Ohms can be measured only on a non-powered
circuit.± Voltage between any terminal and ground
must not exceed 500v DC or 500v peak AC.
± Use caution when measuring voltage above
25v DC or 25v AC.
± The circuit being tested must be protected by a
10 amp fuse or circuit breaker.
± Use the low current shunt to measure circuits
up to 10 amps. Use the high current shunt to
measure circuits exceeding 10 amps.
± When testing for the presence of voltage or
current, make sure the meter is functioning
correctly. Take a reading of a known voltage or
current before accepting a zero reading.
± When measuring current, connect the meter in
series with the load.
± Disconnect the live test lead before disconnect-
ing the common test lead.
4.3 WARNINGS AND CAUTIONS
4.3.1 ROAD TEST WARNINGS
Some complaints will require a test drive as part
of the repair verification procedure. The purpose of
the test drive is to try to duplicate the diagnostic
code or symptom condition.
CAUTION: Before road testing a vehicle, be
sure that all components are reassembled.
During the test drive, do not hang the DRBIIIT
from the rear view mirror. Do not attempt to
read the DRBIIITwhile driving. Have an
assistant available to operate the DRBIIIT.
4.3.2 VEHICLE DAMAGE CAUTIONS
Before disconnecting any control module, make
sure the ignition is off. Failure to do so could
damage the module. When testing voltage or circuit
integrity at any control module, use the terminal
side (not the wire end) of the harness connector. Do
not probe through the insulation; this will damage
it and eventually cause it to fail because of corro-
sion.
Be careful when performing electrical test so as to
prevent accidental shorting of terminals. Such a
mistake can damage fuses or components. Also, a
second code could be set, making diagnosis of the
original problem more difficult.
5.0 REQUIRED TOOLS AND
EQUIPMENT
DRBIIIt(diagnostic read-out box) scan tool
vacuum gauge
ammeter
9
GENERAL INFORMATION

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

REAR WINDOW DEFOGGER
RELAY
DESCRIPTION
The left and right rear window defogger (EBL)
relays are International Standards Organization
(ISO)-type relays (Fig. 3). Relays conforming to the
ISO specifications have common physical dimensions,
current capacities, terminal functions and patterns.
The EBL relays are electromechanical devices that
switch battery current through fuse 10 (30 amp)
located in the fuse/relay block under the driver seat
to the rear window defogger grids and when
equipped, switches battery current to the outside
mirror heating grids. The EBL relays are energized
when the relay coils are provided battery current by
the rear window defogger module.
The EBL relays are located in the fuse/relay block
under the driver seat. Refer to the fuse and relay
map located on the inner surface of the fuse/relay
block cover for the left and right rear window defog-
ger (EBL) relay locations.The black, molded plastic case is the most visible
component of the two rear window defogger (EBL)
relays. Five male spade-type terminals extend from
the bottom of the base to connect each relay to the
vehicle electrical system, and the ISO designation for
each terminal is molded into the base adjacent to
each terminal.
OPERATION
The left and right rear window defogger (EBL)
relays are electromechanical switches that uses a low
current input from the rear window defogger module
to control the high current output to the rear window
defogger grids. The movable common feed contact
point is held against the fixed normally closed con-
tact point by spring pressure. When the relay coil is
energized, an electromagnetic field is produced by the
coil windings. This electromagnetic field draws the
movable relay contact point away from the fixed nor-
mally closed contact point, and holds it against the
fixed normally open contact point. When the relay
coil is de-energized, spring pressure returns the mov-
able contact point back against the fixed normally
closed contact point. The resistor or diode is con-
nected in parallel with the relay coil in the relay, and
helps to dissipate voltage spikes and electromagnetic
interference that can be generated as the electromag-
netic field of the relay coil collapses.
The EBL relay terminals are connected to the vehi-
cle electrical system through receptacles in the fuse/
relay block. The inputs and outputs of the EBL
relays include:
²The common feed terminal (30) receives a bat-
tery current input from fuse 10 (30 amp) in the fuse/
relay block through a fused B(+) circuit at all times.
Fig. 2 Grid Line Test
1 - VOLTMETER
2 - VOLTAGE FEED (A)
3 - FEED WIRE
4 - MID-POINT (C)
5 - HEATED WINDOW GRID
6 - GROUND WIRE
7 - GROUND (B)
Fig. 3 Rear Window Defogger (EBL) Relays
1 - REAR WINDOW DEFOGGER (EBL) RELAY (2)
2 - TERMINAL PATTERN
VAHEATED GLASS 8G - 3