Dodge R1500 1999 Service Manual page 282

1999 ENGINE PERFORMANCE
CHRY - Basic Diagnostic Procedures - Trucks - Diesel
Ram Pickup
INTRODUCTION
The following diagnostic steps will help prevent overlooking
a simple problem. This is also where to begin diagnosis for a no-start
condition.
The first step in diagnosing any driveability problem is
verifying the customer's complaint with a test drive under the
conditions the problem reportedly occurred.
Before entering self-diagnostics, perform a careful and
complete visual inspection. Most engine control problems result from
mechanical breakdowns or poor electrical connections. Before
condemning the computerized system, perform each test listed in this
article.
Two different module systems are used for powertrain control
of diesel engine. The Engine Control Module (ECM), located on left
side of engine, is used to control the fuel system. See Fig. 1. The
Fuel Pump Control Module (FPCM) located on pump, is a separate
component of ECM.
The Powertrain Control Module (PCM), located at right rear of
engine compartment, is used for charging system, transmission and
speed control functions. CCD Bus circuits connect the various vehicle
control modules. These circuits are connected between ECM and PCM to
allow communication between modules.
Fig. 1: Locating Fuel System & Various Engine Components
Courtesy of Chrysler Corp.
PRELIMINARY INSPECTION & ADJUSTMENTS
F - BASIC TESTING - DIESEL
1999 Dodge Pickup R1500