2006 MERCEDES-BENZ SPRINTER check engine

Symptom:
NO COMMUNICATION WITH ECM
When Monitored and Set Condition:
NO COMMUNICATION WITH ECM
When Monitored: Ignition On - Continuously
Set Condition: When the CAB fails to receive all messages from the ECM.
POSSIBLE CAUSES
NO COMMUNICATION WITH BUS
ENGINE CONTROL MODULE DTC(S) PRESENT
ENGINE CONTROL MODULE'S POWER/GROUND CIRCUIT(S) SHORTED OR OPEN
CAN C BUS (+)/CAN C BUS (-) CIRCUIT(S) OPEN TO ENGINE CONTROL MODULE
CAN C BUS (+)/CAN C BUS (-) CIRCUIT(S) OPEN TO CAB
ANTI-LOCK BRAKE CONTROLLER
ENGINE CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, read CAB DTCs.
Does the DRBIIItdisplay: NO COMMUNICATION WITH BUS?All
Ye s!Refer to the symptom list for the appropriate diagnostic proce-
dure.
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 2
2 Turn the ignition on.
With the DRBIIIt, read ECM DTCs.
Does the DRBIIItdisplay any DTCs?All
Ye s!Refer to Powertrain Diagnostic information for the related symp-
tom(s).
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 3
3 Turn the ignition on.
With the DRBIIIt, check the TCM, IC, and ATC module for the same or similar No
Communication with Engine Control Module DTC.
Does the DRBIIItdisplay same or similar DTC in TCM, IC, & ATC module?All
Ye s!Go To 4
No!Go To 6
52
BRAKES (CAB)

TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the ECM harness connectors.
Check all of the ECM's power circuits for a short or open condition.
Check all of the ECM's ground circuits for an open condition.
Were any problems found?All
Ye s!Repair the power/ground circuit(s) as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 5
5 Turn the ignition off.
Disconnect the ECM harness connectors.
Measure the resistance between the CAN C Bus (+) circuit and the CAN C Bus (-)
circuit in the ECM harness connector.
Is the resistance 57 to 63 ohms?All
Ye s!Replace the Engine Control Module in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.
No!Repair the CAN C Bus (+)/CAN C Bus (-) circuit(s) for an open.
Perform ABS VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Disconnect the CAB harness connector.
Measure the resistance between the CAN C Bus (+) circuit and the CAN C Bus (-)
circuit in the CAB harness connector.
Is the resistance 57 to 63 ohms?All
Ye s!Replace the Controller Antilock Brake in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.
No!Repair the CAN C Bus (+)/CAN C Bus (-) circuit(s) for an open.
Perform ABS VERIFICATION TEST - VER 1.
53
BRAKES (CAB)
NO COMMUNICATION WITH ECM ÐContinued

Symptom:
SYSTEM OVERVOLTAGE
POSSIBLE CAUSES
INTERMITTENT DTC
DAMAGED CAB/CAB HARNESS CONNECTOR
GROUND CIRCUIT OPEN
ANTI-LOCK BRAKE CONTROLLER
TEST ACTION APPLICABILITY
1NOTE: Repair any Powertrain charging system DTCs before continuing.
Turn the ignition on.
With the DRBIIIt, read DTCs.
With the DRBIIIt, erase DTCs.
Turn the ignition off.
Turn the ignition on.
Start the engine.
With the DRBIIIt, read DTCs.
Does this DTC reset?All
Ye s!Go To 2
No!Go To 4
2 Turn the ignition off.
Disconnect the CAB harness connector.
Inspect the CAB/CAB harness connector for damage.
Is there any broken, bent, pushed out, corroded or spread terminals?All
Ye s!Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 3
3 Turn the ignition off.
Disconnect the CAB harness connector.
Using a 12-volt test light connected to 12-volts, check the CAB harness connector
Ground circuits.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s!Replace the Controller Antilock Brake in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.
No!Repair the Ground circuit for an open.
Perform ABS VERIFICATION TEST - VER 1.
75
BRAKES (CAB)

Symptom:
SYSTEM UNDERVOLTAGE
POSSIBLE CAUSES
INTERMITTENT DTC
DAMAGED CAB/CAB HARNESS CONNECTOR
FUSED OPTIONAL EQUIPMENT RELAY OUTPUT CIRCUIT HIGH RESISTANCE
FUSED B(+) CIRCUIT HIGH RESISTANCE
GROUND CIRCUIT HIGH RESISTANCE
ANTI-LOCK BRAKE CONTROLLER
TEST ACTION APPLICABILITY
1NOTE: An undercharged battery may cause this DTC to set. Repair any
Powertrain charging system DTCs before continuing.
Turn the ignition on.
With the DRBIIIt, read DTCs.
With the DRBIIIt, erase DTCs.
Turn the ignition off.
Turn the ignition on.
Start the engine.
With the DRBIIIt, read DTCs.
Does this DTC reset?All
Ye s!Go To 2
No!Go To 6
2 Turn the ignition off.
Disconnect the CAB harness connector.
Inspect the CAB/CAB harness connector for damage.
Is there any broken, bent, pushed out, corroded or spread terminals?All
Ye s!Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 3
3 Turn the ignition off.
Disconnect the CAB harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, check the Fused Optional Equipment
Relay Output circuit at the CAB harness connector.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s!Go To 4
No!Repair the Fused Optional Equipment Relay Output circuit for
high resistance.
Perform ABS VERIFICATION TEST - VER 1.
77
BRAKES (CAB)

TABLE OF CONTENTS - Continued
*CHECKING THE FUEL PRESSURE SOLENOID CIRCUITS...................233
*CHECKING THE FUEL QUANTITY SOLENOID CIRCUITS....................234
*CHECKING THE POWER AND GROUNDS................................235
*ENGINE CRANKS BUT WILL NOT START.................................239
*ENGINE WILL NOT CRANK.............................................242
VERIFICATION TESTS
VERIFICATION TESTS..................................................246
8.0 COMPONENT LOCATIONS..............................................249
8.1CONTROL MODULES.............................................249
8.2CONTROLS AND SOLENOIDS......................................249
8.3DATA LINK CONNECTOR..........................................250
8.4SENSORS.......................................................251
8.5SWITCHES......................................................253
9.0 CONNECTOR PINOUTS................................................255
ACCELERATOR PEDAL POSITION SENSOR (OBD).........................255
AIRBAG CONTROL MODULE - YELLOW...................................255
BOOST PRESSURE SENSOR (OBD)......................................255
BOOST PRESSURE SERVOMOTOR (OBD)................................256
CAMSHAFT POSITION SENSOR - BLACK.................................256
CONTROLLER ANTILOCK BRAKE........................................257
CRANKCASE HEATER - BLACK..........................................257
CRANKSHAFT POSITION SENSOR - BLACK...............................258
DATA LINK CONNECTOR - BLACK........................................258
EGR VALVE - BLACK...................................................258
ENGINE CONTROL MODULE C1 (OBD)...................................259
ENGINE CONTROL MODULE C2 (OBD)...................................260
ENGINE COOLANT TEMPERATURE SENSOR - BLACK......................260
ENGINE OIL SENSOR - BLACK..........................................261
FUEL INJECTOR NO. 1 - BLACK.........................................261
FUEL INJECTOR NO. 2 - BLACK.........................................261
FUEL INJECTOR NO. 3 - BLACK.........................................261
FUEL INJECTOR NO. 4 - BLACK.........................................262
FUEL INJECTOR NO. 5 - BLACK.........................................262
FUEL PRESSURE SENSOR - BLACK.....................................262
FUEL PRESSURE SOLENOID............................................262
FUEL PUMP (OBD).....................................................262
FUEL PUMP RELAY (OBD)..............................................263
FUEL QUANTITY CONTROL VALVE (OBD).................................263
FUEL TEMPERATURE SENSOR..........................................263
ENGINE CONTROL RELAY (FUSE BLOCK NO. 1)...........................265
FUSES (FUSE BLOCK NO. 1)............................................265
FUSES (FUSE BLOCK NO. 2)............................................267
FUSES (FUSE/RELAY BLOCK)...........................................269
STARTER MOTOR RELAY (FUSE/RELAY BLOCK)...........................269
GLOW PLUG CONTROL MODULE C1 - BLACK.............................270
GLOW PLUG CONTROL MODULE C2 - BLACK.............................270
INTAKE AIR PRESSURE SENSOR (OBD)..................................270
INTAKE AIR TEMPERATURE SENSOR - BLACK............................270
x

3.2.2 ECM OPERATING MODES
As input signals to the ECM change, the ECM
adjusts its response to the output devices. For
example, the ECM must calculate a different fuel
quantity and fuel timing for engine idle condition
than it would for a wide open throttle condition.
There are several different modes of operation that
determine how the ECM responds to the various
input signals.
Ignition Switch On (Engine Off)
When the ignition is turned on the ECM activates
the glow plug relay for a time period that is deter-
mined by engine coolant temperature, intake air
temperature and battery voltage.
Engine Start-Up Mode
The ECM uses the intake air temperature sensor,
engine temperature sensor and the crankshaft po-
sition sensor (engine speed) inputs to determine
fuel injection quantity.
Normal Driving Modes
Engine idle, warm-up, acceleration, deceleration
and wide open throttle modes are controlled based
on all of the sensor inputs to the ECM. The ECM
uses these sensor inputs to adjust fuel quantity and
fuel injector timing. EGR valve control is performed
using feedback from the oxygen sensor. An oxygen
sensor is located in the exhaust manifold to sample
oxygen content exiting the engine cylinders. The
ECM uses the O2 sensor, along with other sensor
inputs, to govern the amount of exhaust gas recir-
culation to reduce HC (HydroCarbons) and CO
(Carbon Monoxide). Engine coolant is routed
through the base of the EGR valve to provide
additional cooling of the exhaust gas, which further
helps the reductions of emissions. The EGR valve
has a self-cleaning function. When the engine is
shut off, the EGR valve rotates twice to reduce
carbon deposits at the valve seat.
Overheat Production Mode
If the engine temperature is above 105ÉC (221ÉF)
and vehicle speed is above 40 km/h (25 MPH) the
ECM will limit fuel quantity for engine protection.
Limp-In Mode
The ECM utilizes different degrees of engine
limp-in. The ECM is able to limit engine rpm,
engine power output (turbo boost reduction), acti-
vate engine cooling fan or all of these functions
based on the type of fault that is detected. Critical
engine performance faults such as accelerator pedal
position sensor fault will result in a fixed idle speed
of approximately 680 rpm regardless of actual pedalposition. Other less critical faults will result in
power reduction throughout the full range of driv-
ing conditions.
Overspeed Detection Mode
If the ECM detects engine RPM that exceeds
5200 RPM, the ECM will set a DTC in memory,
limit engine RPM to no more than 2500 RPM, and
illuminate the MIL until the DTC is cleared.
After-Run Mode
The ECM transfers RAM information to ROM
and performs an Input/Output state check.
3.2.3 MONITORED CIRCUITS
The ECM is able to monitor and identify most
driveability related trouble conditions. Some cir-
cuits are directly monitored through ECM feedback
circuitry. In addition, the ECM monitors the voltage
state of some circuits and compares those states
with expected values. Other systems are monitored
indirectly when the ECM conducts a rationality test
to identify problems.
Although most subsystems of the engine control
module are either directly or indirectly monitored,
there may be occasions when diagnostic trouble
codes are not immediately identified. For a trouble
code to set, a specific set of conditions must occur
and unless these conditions occur, a DTC will not
set.
3.2.4 SKREEM OVERVIEW
The sentry key remote entry module system
(SKREEM) is designed to prevent unauthorized
vehicle operation. The system consists of a sentry
key remote entry module (SKREEM), ignition
key(s) equipped with a transponder chip and the
ECM. When the ignition switch is turned on, the
SKREEM interrogates the ignition key. If the igni-
tion key is Valid or Invalid, the SKREEM sends a
message to the ECM indicating ignition key status.
Upon receiving this message the ECM will termi-
nate engine operation or allow the engine to con-
tinue to operate.
3.2.5 SKREEM ON-BOARD DIAGNOSTICS
The SKREEM has been programmed to transmit
and monitor many different coded messages as well
as CAN Bus messages. This monitoring is called
On-Board Diagnostics. Certain criteria must be met
for a DTC to be entered into SKREEM memory. The
criteria may be a range of; input voltage, CAN Bus
message or coded messages to the SKREEM. If all
the criteria for monitoring a circuit or function are
met and a fault is detected, a DTC will be stored in
the SKREEM memory and the START ERROR indi-
cator will be turned on in the instrument cluster.
2
GENERAL INFORMATION

3.2.6 SKREEM OPERATION
When ignition power is supplied to the SKREEM,
the SKREEM performs an internal self-test. After
the self-test is complete, the SKREEM energizes
the antenna (this activates the transponder chip)
and sends a challenge to the transponder chip. The
transponder chip responds to the challenge by gen-
erating an encrypted response message.
After responding to the coded message, the tran-
sponder sends a transponder ID message to the
SKREEM. The SKREEM compares the transpon-
der ID message to the available valid key codes in
SKREEM memory (8 key maximum at any one
time). After validating the ignition key the
SKREEM sends a CAN Bus message request to the
ECM, then waits for the ECM response. If the ECM
does not respond, the SKREEM will send the re-
quest again. If the ECM does not respond again, the
SKREEM will stop sending the request and store a
trouble code in memory. If the ECM sends a correct
response to the SKREEM, the SKREEM sends a
valid/invalid key message to the ECM. The ECM
will allow or disallow engine operation based on this
message.
Secret Key - an electronically stored value (iden-
tification number) that is unique to each SKREEM.
The secret key is stored in the SKREEM, ECM and
all ignition key transponders.
Challenge - a random number that is generated by
the SKREEM at each ignition key cycle.
The secret key and challenge are the two vari-
ables used in the algorithm that produces the
encrypted response message. The transponder uses
the crypto algorithm to receive, decode and respond
to the message sent by the SKREEM. After re-
sponding to the coded message, the transponder
sends a transponder ID message to the SKREEM.
3.3 DIAGNOSTIC TROUBLE CODES
Each diagnostic trouble code (DTC) is diagnosed
by following a specific procedure. The diagnostic
test procedure contains step-by-step instruction for
determining the cause of the DTC as well as no
trouble code problems. It is not necessary to per-
form all of the tests in this book to diagnose an
individual code.
Always begin diagnosis by reading the DTCs
using the DRBIIIt. This will direct you to the
specific test(s) that must be performed.
3.3.1 HARD CODE
A DTC that comes back within one cycle of the
ignition key is a hard code. This means that the
problem is current every time the ECM/SKREEM
checks that circuit or function. Procedures in this
manual verify if the DTC is a hard code at thebeginning of each test. When the fault is not a hard
code, an intermittent test must be performed.
NOTE: If the DRBIIITdisplays faults for
multiple components (i.e. ECT, MAF, IAT
sensors) identify and check the shared
circuits for possible problems before
continuing (i.e. sensor grounds or 5-volt
supply circuits). Refer to the appropriate
schematic to identify shared circuits.
3.3.2 INTERMITTENT CODE
A DTC that is not current every time the ECM/
SKREEM checks the circuit or function is an inter-
mittent code. Most intermittent DTCs are caused
by wiring or connector problems. Problems that
come and go like this are the most difficult to
diagnose; they must be looked for under specific
conditions that cause them. The following checks
may assist you in identifying a possible intermit-
tent problem.
± Visually inspect the related wire harness con-
nectors. Look for broken, bent, pushed out or
corroded terminals.
± Visually inspect the related wire harness.
Look for chafed, pierced or partially broken
wire.
± Refer to hotlines or technical service bulletins
that may apply.
NOTE: Electromagnetic (radio) interference
can cause an intermittent system
malfunction. This interference can interrupt
communication between the ignition key
transponder and the SKREEM.
3.3.3 ECM DIAGNOSTIC TROUBLE CODES
IMPORTANT NOTE: Before replacing the
ECM for a failed driver, control circuit or
ground circuit, be sure to check the related
component/circuit integrity for failures not
detected due to a double fault in the circuit.
Most ECM driver/control circuit failures are
caused by internal failures to components
(i.e. relays and solenoids) and shorted
circuits (i.e. sensor pull-ups, drivers and
ground circuits). These faults are difficult to
detect when a double fault has occurred and
only one DTC has set.
If the DRBIIItdisplays faults for multiple com-
ponents (i.e. MAF, ECT, ENG OIL, etc.), identify
and check the shared circuits for possible problems
before continuing (i.e. sensor grounds or 5-volt
3
GENERAL INFORMATION

3.3.4 HANDLING NO TROUBLE CODE
PROBLEMS
After reading Section 3.0 (System Description
and Functional Operation), you should have a bet-
ter understanding of the theory and operation of the
on-board diagnostics and how this relates to the
diagnosis of a vehicle that may have a driveability-
related symptom or complaint. When there are no
trouble codes present, refer to the no trouble code
(*) tests.
3.4 USING THE DRBIIIT
Refer to the DRBIIItuser 's guide for instructions
and assistance with reading the DTCs, erasing the
DTCs, lab scope usage and other DRBIIItfunc-
tions.
3.4.1 DRBIIITDOES NOT POWER UP
If the LEDs do not light or no sound is emitted at
start up, check for loose cable connections or a bad
cable. Check the vehicle battery voltage at data link
connector cavity 16. A minimum of 11.0 volts is
required to adequately power the DRBIIIt. Check
for proper ground connection at data link connector
cavities 4 and 5.
If all connections are proper between the
DRBIIItand the vehicle or other devices, and the
vehicle battery is fully charged, an inoperative
DRBIIItmay be the result of a faulty cable or
vehicle wiring. For a blank screen, refer to the
appropriate diagnostic manual.
3.4.2 DISPLAY IS NOT VISIBLE
Low temperatures will affect the visibility of the
display. Adjust the contrast to compensate for this
condition.
4.0 DISCLAIMERS, SAFETY,
WARNINGS
4.1 DISCLAIMERS
All information, illustrations and specifications
contained in this manual are based on the latest
information available at the time of publication.
The right is reserved to make changes at any time
without notice.
4.2 SAFETY
4.2.1 TECHNICIAN SAFETY INFORMATION
WARNING: HIGH-PRESSURE FUEL LINES
DELIVER DIESEL FUEL UNDER EXTREME
PRESSURE FROM THE INJECTION PUMP TO
THE FUEL INJECTORS. THIS MAY BE AS
HIGH AS 23,200 PSI (1600 BAR). USE
EXTREME CAUTION WHEN INSPECTING
FOR HIGH-PRESSURE FUEL LEAKS. FUEL
UNDER THIS AMOUNT OF PRESSURE CAN
PENETRATE SKIN CAUSING PERSONAL
INJURY OR DEATH. INSPECT FOR
HIGH-PRESSURE FUEL LEAKS WITH A
SHEET OF CARDBOARD. WEAR SAFETY
GOGGLES AND ADEQUATE PROTECTIVE
CLOTHING WHEN SERVICING FUEL
SYSTEM.
WARNING: ENGINES PRODUCE CARBON
MONOXIDE THAT IS ODORLESS, CAUSES
SLOWER REACTION TIME AND CAN LEAD
TO SERIOUS INJURY. WHEN THE ENGINE IS
OPERATING, KEEP SERVICE AREA WELL
VENTILATED OR ATTACH THE VEHICLE
EXHAUST SYSTEM TO THE SHOP EXHAUST
REMOVAL SYSTEM.
Set the parking brake and block the wheels before
testing or repairing the vehicle. It is especially
important to block the wheels on front wheel drive
vehicles; the parking brake does not hold the drive
wheels.
When servicing a vehicle, always wear eye pro-
tection and remove any metal jewelry such as
watchbands or bracelets that might make electrical
contact.
When diagnosing powertrain system problems, it
is important to follow approved procedures where
applicable. These procedures can be found in the
8
GENERAL INFORMATION