Introduction; System Coverage; Six-Step Troubleshooting Procedure; Identification Of System - Mercedes-Benz Sprinter 2003 Manual

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 DRBIII is communicating
with the appropriate modules; i.e., if the
DRBIII displays a ''No Response'' or a ''Bus
Signals Open'' condition, you must diagnose that
first.
2. Read DTC's (diagnostic trouble codes) with the
DRBIII .
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:
• verification of complaint
GENERAL INFORMATION
•
verification of any related symptoms
•
symptom analysis
• problem isolation
• repair of isolated problem
•
verification of proper operation
2.0 IDENTIFICATION OF
SYSTEM
The vehicle systems that are part of the ''body''
system are:
•
Airbag
• Automatic Temperature Control
• Communication
•
Instrument Cluster
•
Power Door Locks/RKE
• Vehicle Theft Security System (VTSS)
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 DRBIII utilizes 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:
• Airbag Control Module (ACM)
• Airbag Warning Indicator (SRS)
•
Driver Airbags
• Clockspring
• Passenger Airbag
• Driver Seat Belt Tensioners
•
Passenger 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
secured to the floor under the Driver seat and
1