
TABLE OF CONTENTS
1.0 INTRODUCTION.........................................................1
1.1SYSTEM COVERAGE...............................................1
1.2SIX-STEP TROUBLESHOOTING PROCEDURE..........................1
2.0 IDENTIFICATION OF SYSTEM.............................................1
3.0 SYSTEM DESCRIPTION AND FUNCTIONAL OPERATION......................1
3.1AIRBAG SYSTEM...................................................1
3.1.1DRIVER AIRBAG............................................2
3.1.2CLOCKSPRING.............................................3
3.1.3PASSENGER AIRBAG.......................................3
3.1.4SEAT BELT TENSIONERS....................................3
3.1.5SPECIAL TOOLS............................................3
3.1.6DIAGNOSTIC TROUBLE CODES..............................4
3.1.6.1ACTIVE CODES............................................4
3.1.6.2STORED CODES...........................................4
3.2COMMUNICATION..................................................4
3.2.1COMMUNICATION K-LINES..................................4
3.2.2CAN BUS..................................................5
3.3HEATING & A/C SYSTEM............................................5
3.3.1AUTOMATIC TEMPERATURE CONTROL (ATC)..................5
3.3.1.1SYSTEM CONTROLS........................................5
3.3.1.2SYSTEM DIAGNOSTICS.....................................5
3.3.2CABIN HEATER MODULE (CHM) & HEATER BOOSTER MODULE
(HBM).....................................................7
3.3.2.1SYSTEM DESCRIPTION.....................................7
3.3.2.2VENTING THE HEATER'S EXHAUST...........................8
3.3.2.3SYSTEM DIAGNOSTICS.....................................8
3.4INSTRUMENT CLUSTER.............................................9
3.5POWER DOOR LOCKS/RKE..........................................9
3.5.1CENTRAL LOCKING.........................................9
3.5.2REMOTE KEYLESS ENTRY (RKE).............................9
3.5.3AUTO DOOR LOCKS.......................................10
3.5.4ACCIDENT RESPONSE.....................................10
3.6VEHICLE THEFT SECURITY SYSTEM (VTSS)..........................10
3.7USING THE DRBIIIT................................................11
3.8DRBIIITERROR MESSAGES.........................................11
3.9DRBIIITDOES NOT POWER UP (BLANK SCREEN)......................11
3.10DISPLAY IS NOT VISIBLE...........................................11
4.0 DISCLAIMERS, SAFETY, WARNINGS......................................11
4.1DISCLAIMERS.....................................................11
4.2SAFETY..........................................................11
4.2.1TECHNICIAN SAFETY INFORMATION.........................11
4.2.2VEHICLE PREPARATION FOR TESTING.......................12
4.2.3SERVICING SUB-ASSEMBLIES..............................12
4.2.4DRBIIITSAFETY INFORMATION.............................12
4.3WARNINGS.......................................................12
4.3.1VEHICLE DAMAGE WARNINGS..............................12
4.3.2ROAD TESTING A COMPLAINT VEHICLE......................12
i

1.0 INTRODUCTION
The procedures contained in this manual include
all the specifications, instructions and graphics
needed to diagnose Sprinter body system problems.
The diagnostics in this manual are based on the
failure condition or symptom being present at the
time of diagnosis.
Please follow the recommendations below when
choosing your diagnostic path.
1. First make sure the DRBIIItis communicating
with the appropriate modules; i.e., if the
DRBIIItdisplays a ``No Response'' or a ``Bus6
Signals Open'' condition, you must diagnose that
first.
2. Read DTC's (diagnostic trouble codes) with the
DRBIIIt.
3. If no DTC's are present, identify the customer
complaint.
4. Once the DTC or customer complaint is identi-
fied, locate the matching test in the Table of
Contents and begin to diagnose the symptom.
All component location views are in Section 8.0.
All connector pinouts are in Section 9.0. All sche-
matics are in Section 10.0. All Charts and Graphs
are in Section 11.0.
An * placed before the symptom description indi-
cates a customer complaint without a DTC.
When repairs are required, refer to the appropri-
ate service information for the proper removal and
repair procedure.
Diagnostic procedures change every year. New
diagnostic systems may be added: carryover sys-
tems may be enhanced. READ THIS MANUAL
BEFORE TRYING TO DIAGNOSE A VEHICLE
DIAGNOSTIC TROUBLE CODE. It is recom-
mended that you review the entire manual to be-
come familiar with all the new and changed diag-
nostic procedures.
This book reflects many suggested changes from
readers of past issues. After using this book, if you
have any comments or suggestions, please fill out
the form in the back of this book and mail it back to
us.
1.1 SYSTEM COVERAGE
This diagnostic procedures manual covers all
Sprinter vehicles.
1.2 SIX-STEP TROUBLESHOOTING
PROCEDURE
Diagnosis of the body system is done in six basic
steps:
²verification of complaint
²verification of any related symptoms
²symptom analysis
²problem isolation
²repair of isolated problem
²verification of proper operation
2.0 IDENTIFICATION OF
SYSTEM
The vehicle systems that are part of the ``body''
system are:
²Airbag
²Automatic Temperature Control
²Communication
²Instrument Cluster
²Power Door Locks/RKE
²Vehicle Theft Security System (VTSS)
²Wiper/Rain Sensor
3.0 SYSTEM DESCRIPTION AND
FUNCTIONAL OPERATION
The body system on the Sprinter consists of a
combination of modules that communicate with
each other using the CAN Bus (controller area
network). Through the CAN Bus, information about
the operation of vehicle components and circuits is
relayed quickly to the appropriate modules. Since
the CAN bus network is for intermodule communi-
cation only, the DRBIIItutilizes K-Lines to estab-
lish communications with each module. It is impor-
tant to note the CAN bus circuits are by no means
tied to the K-Lines. They are completely separate
from each other. For additional information on the
CAN bus and the K-Lines, refer to the Communi-
cation section of this general information.
3.1 AIRBAG SYSTEM
The Sprinter Airbag System contains the follow-
ing components:
²Airbag Control Module (ACM)
²Airbag Warning Indicator (SRS)
²Driver Airbags
²Clockspring
²Passenger Airbag
²Driver Seat Belt Tensioners
²Passenger Seat Belt Tensioners
The Airbag Control Module (ACM) has five major
functions: onboard diagnostics, determine the se-
verity of impacts, squib deployment and Accident
Response, K-Line communications. The ACM is
1
GENERAL INFORMATION

loads are connected to cables and mounted in a
storage case. The cables can be directly connected to
some airbag system connectors. Jumpers are used
to convert the load tool cable connectors to the other
airbag system connectors. The adapters are con-
nected to the module harness connector to open
shorting clips and protect the connector terminal
during testing. When using the load tool follow all of
the safety procedures in the service information for
disconnecting airbag system components. Inspect
the wiring, connector and terminals for damage or
misalignment. Substitute the airbag load tool in
place of a Driver or Passenger Airbag, seat belt
tensioner, clockspring (use a jumper if needed).
Then follow all of the safety procedures in the
service information for connecting airbag system
components. Read the module active DTCs. If the
module reports NO ACTIVE DTCs the defective
components has been removed from the system and
should be replaced. If the DTC is still active, con-
tinue this process until all components in the circuit
have been tested. Then disconnect the module con-
nector and connect the matching adapter to the
module connector. With all airbags disconnected
and the adapter installed the squib wiring can be
tested for open and shorted conditions.
3.1.6 DIAGNOSTIC TROUBLE CODES
Airbag diagnostic trouble codes consist of active
and stored codes. If more than one code exists,
diagnostic priority should be given to the active
codes. Each diagnostic trouble code is diagnosed by
following a specific testing procedure. The diagnos-
tic test procedures contain step-by-step instructions
for determining the cause of the trouble codes. It is
not necessary to perform all of the tests in this book
to diagnose an individual code. Always begin by
reading the diagnostic trouble codes with the
DRBIIIt. This will direct you to the specific test(s)
that must be performed. In certain test procedures
within this manual, diagnostic trouble codes are
used as a diagnostic tool.
3.1.6.1 ACTIVE CODES
If the lamp remains on, there could be an active
DTC in the system. The code becomes active as soon
as the malfunction is detected or key-on, whichever
occurs first. An active trouble code indicates an
on-going malfunction. This means that the defect is
currently there every time the airbag control mod-
ule checks that circuit or component. Some DTCs,
Internal Module and squib DTCs, will keep the
indicator illuminated even if they are no longer
active. If the lamp is on and no active codes are
present, cycling the ignition switch off and then on
will refresh the lamp state. It is impossible to erase
an active code.
3.1.6.2 STORED CODES
Airbag codes are automatically stored in the
ACM's memory as soon as the malfunction is de-
tected. A stored code indicates there was an active
code present at some time. Stored diagnostic trou-
ble code will remain stored until erased by the DRB.
If a malfunction is not active while performing a
diagnostic test procedure, the active code diagnostic
test will not locate the source of the problem. In this
case, the stored code can indicate an area to inspect.
Maintain a safe distance from all airbags while
performing the following inspection. If no obvious
problems are found, erase stored codes, and with
the ignition on wiggle the wire harness and connec-
tors, rotate the steering wheel from stop to stop.
Recheck for codes periodically as you work through
the system. This procedure may uncover a malfunc-
tion that is difficult to locate.
3.2 COMMUNICATION
3.2.1 COMMUNICATION K-LINES
The K-Lines are a group of circuits that connect
each control module to the Data Link Connector
(DLC). Each control module is connected to the DLC
with a single K-Line. The DRBIIItuses the K-Line
to communicate with each control module. With the
use of the K-Lines the DRBIIItis able to read each
control modules DTCs, sensor displays, I/Os etc. If
DRBIIItcommunications with a particular control
module is lost, one of the possible causes could be a
fault in the module's K-Line.
NOTE: It is important to note the DRBIIIT
uses the K-Lines for diagnostic and
monitoring functions and is no way
connected to the CAN data bus network.
The following modules that use the K-line on this
vehicle are:
²Airbag Control Module (ACM)
²Automatic Temperature Control (ATC)
²Cabin Heater Module (CHM)
²Central Timer Module (CTM)
²Controller Antilock Brake (CAB)
²Engine Control Module (ECM)
²Heater Booster Module (HBM)
²Instrument Cluster (IC)
²Shifter Assembly (SA)
²Security System Module (SSM)
²Sentry Key Remote Entry Module (SKREEM)
²Transmission Control Module (TCM)
4
GENERAL INFORMATION

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

1. Connect the DRBIIItto the DLC.
2. Place the shift lever in park.
3. Start the engine.
4. Set the blower to high speed.
5. Set the temperature selector to full cold.
6. Press air conditioning switch on.
7. With the DRBIIItin Sensors, verify that the:
A. ambient temperature is above 59F (15C).
B. refrigerant pressure is between 29 and 348
PSI (2 and 24 bar).
C. evaporator temperature is above 36.5F
(2.5C).
D. coolant temperature is above 158F (70C).
When all of the prerequisites have been met, use
the DRBIIItto record and erase all stored ATC
DTCs, and then select System Tests, and run the
ATC Function Test. When complete, check to see if
any active DTCs are present. If so, refer to the
symptom list in the Heating & A/C category for the
diagnostic procedure(s). If there are no DTCs
present, yet the performance seems less than ideal,
use the DRBIIItto look at all sensor values and the
status of the various inputs and outputs to see if
there is a deficiency detected that has not fully shut
down the system. For additional information, refer
to Sensor Values and Input/Output Status under
Diagnostic Tips in this section and to Section 11.0
for evaporator temperature sensor and air outlet
temperature sensor resistance to temperature spec-
ifications charts. Also, confirm that the water cycle
valve is functioning. Remember that the valve is
normally open. The pulse width signal will offer
insight into the valve's operation. The lower the
percentage number, the more open the valve be-
comes. Confirm that the valve is responding to the
signal from the ATC. If functioning correctly, verify
mode and blend door operation. If okay, the diagno-
sis then becomes purely refrigerant system related.
Attach the appropriate gauges and diagnose the
refrigeration system. Refer to the Service Informa-
tion for refrigerant system diagnostic procedures.
DIAGNOSTIC TIPS
SENSOR VALUES
Ambient Air Temperature
The Instrument Cluster transmits Ambient Air
Temperature Sensor data. In the event of a CAN
Bus communication failure, the last stored value is
displayed as a substitute value.
Interior Temperature
The normal range for the Interior Temperature
Sensor is from 32ÉF to 104ÉF. An implausible tem-
perature value indicates that the Interior Temper-
ature Sensor is bad. The repair in this case would be
to replace the ATC Module since the sensor is
integral to the module.Evaporator Temperature
The normal range for the Evaporator Temperature
Sensor is from 14ÉF to 104ÉF. A substitute value of
14ÉF with no updates indicates an Evaporator Tem-
perature Sensor circuit failure.
Air Outlet Temperature
The normal range for the Air Outlet Temperature
Sensor is from 32ÉF to 203ÉF. A substitute value of
111.1ÉF indicates an Air Outlet Temperature Sensor
circuit failure.
Coolant Temperature
The Engine Control Module transmits Coolant
Temperature Sensor date. In the event of a CAN
Bus communication failure, 257ÉF is displayed as a
substitute value.
Interior Temperature Controller
The normal range for the Blend control is from 62ÉF
to 144ÉF. This value represents the temperature set
by the operator. An implausible temperature value
or a temperature value that fails to change when
rotating the Blend control indicates that the Blend
control is bad. The repair in this case would be to
replace the ATC Module since the Blend control
integral to the module.
Refrigerant Pressure
The normal range for the Refrigerant Pressure
Sensor is from 29 PSI to 406 PSI. A substitute value
of 413 PSI indicates a Refrigerant Pressure Sensor
circuit failure. In addition, the normal range for
Pressure Sensor voltage is 0 volts to 5 volts. A value
of 0.9 volts indicates an open voltage supply circuit,
while a value of -999 indicates an open in all three
sensor circuits.
Water Cycle Valve
The normal range of the Water Cycle Valve is from
0% to 100%. The value indicates the extent to which
the valve is closed. A value of 100% indicates that
the valve is fully closed.
Intense Inst Light
The Instrument Cluster transmits this data. The
normal range for lighting intensity is from 0% to
100%. The value indicates the extent to which the
illumination has dimmed. A value of 0% indicates
bright while a value >0% indicates dimming. In the
event of a CAN Bus communication failure, 0% is
displayed as a substitute value.
INPUT/OUTPUT STATUS
Compressor Clutch
The ATC Module transmits this data. A status of
9ON9indicates that the compressor is operational. A
status of9OFF9indicates the compressor is not
operational.
6
GENERAL INFORMATION

Compres SO Accel (Compressor Shut Off - Due
To Acceleration)
The Engine Control Module transmits this data. A
status of9YES9indicates that the compressor shut
off because of an acceleration request. A status of
9NO9indicates that there is no acceleration request.
If shut off due to an acceleration request, the
compress will switch on again after 20 seconds. In
addition, the original acceleration request can no
longer exist for the ECM to acknowledge a subse-
quent request. In the event of a CAN Bus commu-
nication failure,9NO9is displayed as a substitute
value.
Compres SO W/E-Off (Compressor Shut Off -
Due to Emergency Off)
The Engine Control Module transmits this data. A
status of9YES9indicates that the compressor shut
off because of an emergency off request. A status of
9NO9indicates that there is no emergency off re-
quest. In the event of a CAN Bus communication
failure, the last stored value is displayed as a
substitute value.
Auxiliary Fan
The ATC Module transmits this data. A status of
9ON9indicates that the auxiliary fan is operational.
A status of9OFF9indicates that the auxiliary fan is
not operational. The Auxiliary Fan normally oper-
ates when refrigerant head pressure exceeds 290
PSI and coolant temperature exceeds 221ÉF. In the
event of a CAN Bus communication failure, 257ÉF is
displayed for coolant temperature (in Sensors) and
the Auxiliary Fan will run continuously.
Light PB CTRL Module
This input displays a status of9Bright9for positive
dimmer switch operation and9Dimmed9for nega-
tive dimmer switch operation. In the event of a CAN
Bus communication failure,9Bright9is displayed.
3.3.2 CABIN HEATER MODULE (CHM) &
HEATER BOOSTER MODULE (HBM)
3.3.2.1 SYSTEM DESCRIPTION
WARNING: NEVER OPERATE THE HEATER
IN AN ENCLOSED AREA THAT DOES NOT
HAVE EXHAUST VENTILATION FACILITIES.
ALWAYS VENT THE HEATER'S EXHAUST
WHEN OPERATING THE HEATER. REFER TO
(VENTING THE HEATER'S EXHAUST(
BELOW FOR PROPER EXHAUST VENTING
INSTRUCTIONS. FAILURE TO FOLLOW
THESE INSTRUCTIONS CAN RESULT IN
PERSONAL INJURY OR DEATH.
WARNING: ALLOW THE HEATER ASSEMBLY TO
COOL BEFORE PERFORMING A COMPONENT
INSPECTION/REPAIR/REPLACEMENT. FAILURE
TO FOLLOW THESE INSTRUCTIONS CAN
RESULT IN PERSONAL INJURY OR DEATH.
WARNING: ALWAYS DISCONNECT THE
VEHICLE'S BATTERY PRIOR TO
PERFORMING ANY TYPE OF WORK ON THE
HEATER ASSEMBLY. FAILURE TO FOLLOW
THESE INSTRUCTIONS CAN RESULT IN
PERSONAL INJURY OR DEATH.
WARNING: NEVER ATTEMPT TO REPAIR THE
HEATER ASSEMBLY OR ANY OF ITS
INTERNAL COMPONENTS. ALWAYS
PERFORM HEATER COMPONENT
REPLACEMENT IN ACCORDANCE WITH THE
SERVICE INFORMATION. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN
RESULT IN PERSONAL INJURY OR DEATH.
CAUTION: Always Perform The Heater
Pre-Test (In The Diagnostic Procedures) Prior
To Performing Any Other Test On The Heater
For The Test Result To Be Valid.
NOTE: Do not disconnect the vehicle's
battery or the heater's main power-supply
while the heater is in operation or in
run-down mode. Failure to follow these
instructions may result in excess emissions
from the heater.
NOTE: Failure to prime the Dosing Pump
after draining the fuel line will prevent heater
activation during the first attempt to start the
unit. This may also set a Diagnostic Trouble
Code (DTC) in the control unit's memory. Do
not perform the Dosing Pump Priming
Procedure if an attempt was made to start the
heater without priming the Dosing Pump
first. This will put excess fuel in the heater
module and cause smoke to emit from the
heater's exhaust pipe when heater activation
occurs.
NOTE: Waxed fuel can obstruct the fuel line
and reduce flow. Check for the appropriate
winter grade fuel and replace as necessary.
The Cabin Heater Assembly and Heater Booster
Assembly are supplemental type heaters designed
to pre-heat the engine's coolant in order to supply
the vehicle's occupants with heat prior to the engine
7
GENERAL INFORMATION

reaching operating temperature. The heater's con-
trol unit controls and monitors combustion opera-
tion through various inputs and outputs that are
contained inside the heater assembly. The supple-
mental heater connects to the vehicle's heater hoses
and uses a separate fuel supply line and fuel pump
that connects to the vehicle's fuel tank. Unlike the
Heater Booster, the Cabin Heater Assembly has an
integral coolant pump which allows heater opera-
tion without the vehicle's engine running. In addi-
tion, a programmable timer module can also be
added to this system. Neither the Cabin Heater
Assembly nor the Heater Booster Assembly are
connected to the CAN Bus. Communication be-
tween the heater's control unit and the DRBIIIt
occurs through the Diagnostic Link Connector
(DLC) via a K-Line.
3.3.2.2 VENTING THE HEATER'S EXHAUST
WARNING: NEVER OPERATE THE HEATER
IN AN ENCLOSED AREA THAT DOES NOT
HAVE EXHAUST VENTILATION FACILITIES.
ALWAYS VENT THE HEATER'S EXHAUST
WHEN OPERATING THE HEATER. FAILURE
TO FOLLOW THESE INSTRUCTIONS CAN
RESULT IN PERSONAL INJURY OR DEATH.
WARNING:
ALLOW THE HEATER ASSEMBLY TO
COOL BEFORE PERFORMING A COMPONENT
INSPECTION/REPAIR/REPLACEMENT. FAILURE
TO FOLLOW THESE INSTRUCTIONS CAN
RESULT IN PERSONAL INJURY OR DEATH.
CAUTION: When using a powered exhaust
ventilation system, do not attach the exhaust
ventilation hose directly to the heater's
exhaust pipe. Too much suction can prevent
heater operation.
When using a powered exhaust ventilation sys-
tem, affix the ventilation hose to the heater's ex-
haust pipe or to the vehicle in such a manor that the
end of the ventilation hose remains approximately
three inches away from the end of the heater's
exhaust pipe.
When using a non-powered exhaust ventilation
system, affix the ventilation hose directly to the
heater's exhaust pipe.
3.3.2.3 SYSTEM DIAGNOSTICS
CAUTION: Always Perform The Heater
Pre-Test (In The Diagnostic Procedures) Prior
To Performing Any Other Test For The Test
Result To Be Valid.
Fault detection is through stored Diagnostic
Trouble Codes (DTCs). DTCs are displayed by the
DRBIIIt. The heater's control unit will store up to
five DTCs in its memory. If the control unit detects
a new fault in the system, one that is not already
stored in its memory, it will clear the oldest of the
five stored DTCs, and it will store the new fault's
DTC. If the control unit detects a reoccurrence of a
stored fault, it will overwrite that fault's DTC with
the most recent occurrence.
DIAGNOSTIC TIPS
SENSOR VALUES
Operating Voltage
The normal range for the Operating Voltage is from
10 volts to 15 volts. The value indicates the voltage
at the heater 's Fused B+ terminal.
Heating Capacity
The normal range for the heating capacity is from
0% to 100%. The value indicates the momentary
output of the auxiliary heater in % of the maximum
output.
Coolant Temperature
The value indicates the current coolant tempera-
ture.
Flame Sensor Resistance
The normal range for the Flame Sensor is from 750
ohms to 2270 ohms. The value indicates the mo-
mentary resistance of the Flame Sensor.
INPUT/OUTPUT STATUS
Dosing Pump
A status of9ON9indicates that the Dosing Pump is
operational. A status of9OFF9indicates the Dosing
Pump is not operational.
Glow Pin
A status of9ON9indicates that the Glow Pin is
energized. A status of9OFF9indicates the Glow Pin
is not energized.
Combustion Fan
A status of9ON9indicates that the Combustion Fan
is operational. A status of9OFF9indicates the
Combustion Fan is not operational.
Circulation Pump
A status of9ON9indicates that the Circulation
Pump is operational. A status of9OFF9indicates the
Circulation Pump is not operational.
Front End Blower
A status of9ON9indicates that the Blower Motor is
operational. A status of9OFF9indicates the Blower
Motor is not operational.
8
GENERAL INFORMATION

Static Heater Signal
A status of9ON9indicates that the heater module
sees the9Stationary Heating Mode ON9signal after
switching on the heater with the heater timer or the
auxiliary heater switch. A status of9OFF9indicates
that the9Stationary Heating Mode ON9signal is
not present at the heater module.
Heater Booster Mode Signal
A status of9ON9indicates that the heater module
sees the9Heater Booster Mode ON9signal after
switching on the heater with the auxiliary heater
switch. A status of9OFF9indicates that the9Heater
Booster Mode ON9signal is not present at the
heater module.
3.4 INSTRUMENT CLUSTER
The Instrument Cluster has easy-to-read instru-
ments, is capable of CAN bus communication and
provides a diagnostic function. The Instrument
Cluster with analog speedometer, tachometer, fuel
and coolant temperature gauges comes in two ver-
sions.
²Speedometer with outer miles-per-hour (mph)
scale and inner kilometers-per-hour (km/h) scale.
Coolant temperature is indicated in Fahrenheit
(for US).
²Speedometer with outer kilometers-per-hour
(km/h) scale and inner miles-per-hours (mph)
scale. Coolant temperature is indicated in de-
grees Celsius (for Canada).
Below the speedometer, there is a LCD multi-
function indicator in clear view of the driver. Warn-
ing and indicator lights (based on colored light
emitting diodes) are located in the bottom of the
instrument cluster with the exception of the turn
signal indicator lights, ASR warning light and re-
serve fuel warning light. The warning lights for the
seat belt usage and parking brake/brake fluid level
are located in the line above the bottom line. The
indicator that illuminates up when the parking
brake is applied or the brake fluid level is low is
different for U.S. and Canada.
When the key is turned to the 2nd position in the
ignition, the function of the following indicator
lights is checked automatically: High Beam ON,
Preheating, airbag malfunction. In case of a broken
LED of the airbag malfunction light, the seat belt
usage warning light will flash for 6 seconds after
the function check is finished. The Instrument
Cluster is operated with the help of 4 buttons
located below the multifunction indicator. The back-
lighting for the instrument cluster uses yellow
LED's and can be adjusted electronically to daylight
and darkness.The instrument cluster includes a warning
buzzer, which sounds (in addition to a warning light
in some cases) when:
²The headlights are on with the ignition off and
the door opened.
²The driver 's seat belt is not fastened with the
ignition on.
²The key is in the ignition and the door is open.
²Critical ASSYST information is displayed in the
multifunction indicator.
3.5 POWER DOOR LOCKS/RKE
3.5.1 CENTRAL LOCKING
The Central Locking System locks all vehicle
doors if any door is locked from the inside or
mechanically locked with the key from the outside.
However, unlocking any door, in that manner, will
only unlock that particular door. The Master Door
Lock Switch on the dash enables the operator to
lock/unlock all doors. By pressing the top of the
rocker type switch once, all doors will lock. Pressing
the switch again will unlock all doors. Pressing the
lower part of the switch once will lock all doors
except the driver door. Pressing the lower part
again will unlock all doors except the driver door. If
the Central Locking System automatically unlocks
after the vehicle was attempted to be locked, at
least one door is not properly closed.
There are two LED indicators in the Master Door
Lock Switch. The left indicator is for the driver door
and the right indicator is for all passenger/cargo
doors. These will indicate if a door is ajar or if the
doors are locked. The door ajar switches are part of
the door lock motor and are mounted in the door
latch assembly.
Inside each door lock motor there is a command
switch. The command switch is operated by the
plunger and signals any change in the lock status,
locked or unlocked. Each command switch is wired
to the Central Timer Module (CTM) sometimes
referred to as the Central Locking Module. If all
doors are closed and are unlocked, and any door is
locked by the key or the interior handle, thereby
changing the command switch, all doors will be
locked. If one of the door lock motors does not reach
the end position after a locking command, it will be
detected by the CTM (command switch not in
9Locked9position) and the vehicle will be unlocked.
3.5.2 REMOTE KEYLESS ENTRY (RKE)
The SKREEM is a combination of the Remote
Keyless Entry Module and the SKIM (Sentry Key
Immobilizer Module). It is located behind the In-
strument Cluster and has an antenna that goes up
9
GENERAL INFORMATION