2002 DODGE RAM Service Repair Manual

Page 377 of 2255

DODGE RAM 2002  Service Repair Manual (2) Push the harness connector locks to release the
locks, (Fig. 11) then remove the connectors from the
CAB.
(3) Disconnect the pump motor connector (Fig. 12)
.
(4) Remove screws attaching CAB to the

Page 378 of 2255

DODGE RAM 2002  Service Repair Manual ENGINE CONTROL MODULE
DESCRIPTION - ECM
The ECM is bolted to the left side of the engine
behind the fuel filter (Fig. 14). It is a separate com-
ponent and can be serviced. The FPCM is internal to
the

Page 379 of 2255

DODGE RAM 2002  Service Repair Manual NOTE: ECM Outputs:
After inputs are received by the ECM, certain sen-
sors, switches and components are controlled or reg-
ulated by the ECM. These are consideredECM
Outputs.These outputs are for:
²C

Page 380 of 2255

DODGE RAM 2002  Service Repair Manual POWERTRAIN CONTROL
MODULE
DESCRIPTION
DESCRIPTION - PCM
The Powertrain Control Module (PCM) is located
in the engine compartment (Fig. 17). The PCM is
referred to as JTEC.
DESCRIPTION - MODES OF OPERA

Page 381 of 2255

DODGE RAM 2002  Service Repair Manual The fuel pump is activated by the PCM through
the fuel pump relay.
Voltage is applied to the fuel injectors with the
ASD relay via the PCM. The PCM will then control
the injection sequence and injecto

Page 382 of 2255

DODGE RAM 2002  Service Repair Manual ACCELERATION MODE
This is an Open Loop mode. The PCM recognizes
an abrupt increase in throttle position or MAP pres-
sure as a demand for increased engine output and
vehicle acceleration. The PCM incr

Page 383 of 2255

DODGE RAM 2002  Service Repair Manual OPERATION
OPERATION - PCM - GAS ENGINES
The PCM operates the fuel system. The PCM is a
pre-programmed, triple microprocessor digital com-
puter. It regulates ignition timing, air-fuel ratio,
emission

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DODGE RAM 2002  Service Repair Manual The PCM can adapt its programming to meet
changing operating conditions.
The PCM receives input signals from various
switches and sensors. Based on these inputs, the
PCM regulates various engine and v