Powertrain Control Module; Engine Control Module (Ecm) Location And Mounting; Description - Modes Of Operation; Removal - Dodge 2001 Ram 1500 Owner's Manual

8E - 14 ELECTRONIC CONTROL MODULES
ENGINE CONTROL MODULE (Continued)
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 considered ECM
Outputs. These outputs are for:
• CCD bus (+) circuits
• CCD bus (-) circuits
• CKP and APPS outputs to the PCM
• Data link connection for DRB scan tool
• Five volt sensor supply
• Fuel injection pump
• Fuel injection pump relay
• (FPCM) Fuel Pump Control Module
• Fuel transfer (lift) pump
• Intake manifold air heater relays #1 and #2 con-
trol circuits
• Malfunction indicator lamp (Check engine lamp)
• Oil pressure gauge/warning lamp
• PCM
• Wait-to-start warning lamp
• Water-In-Fuel (WIF) warning lamp

REMOVAL

The ECM is bolted to the engine block behind the
fuel filter (Fig. 16).
Fig. 16 Engine Control Module (ECM) Location and
Mounting
1 - ENGINE CONTROL MODULE (ECM)
2 - HEX HEADED BOLT
3 - 50-WAY CONNECTOR
4 - FUEL TRANSFER PUMP
5 - MOUNTING BOLTS (3)
(1) Record any Diagnostic Trouble Codes (DTC's)
found in the PCM or ECM.
To avoid possible voltage spike damage to either
the Powertrain Control Module (PCM) or ECM, igni-
tion key must be off, and negative battery cables
must be disconnected before unplugging ECM con-
nectors.
(2) Disconnect both negative battery cables at both
batteries.
(3) Remove 50–way electrical connector bolt at
ECM (Fig. 16). Note: Connector bolt is female 4mm
hex head. To remove bolt, use a ball-hex bit or ball-
hex screwdriver such as Snap-On
(5/32" may also be used). As bolt is being removed,
very carefully remove connector from ECM.
(4) Remove three ECM mounting bolts and remove
ECM from vehicle.

INSTALLATION

Do not apply paint to back of ECM. Poor ground
will result.
(1) Clean ECM mounting points at engine block.
(2) Position ECM to engine block and install 3
mounting bolts. Tighten bolts to 24 N·m (18 ft. lbs.).
(3) Check pin connectors in ECM and 50–way con-
nector for corrosion or damage. Repair as necessary.
(4) Clean pins in 50–way electrical connector with
a quick-dry electrical contact cleaner.
(5) Very carefully install 50–way connector to
ECM. Tighten connector hex bolt.
(6) Install battery cables.
(7) Turn key to ON position. Without starting
engine, slowly press throttle pedal to floor and
then slowly release. This step must be done
(one time) to ensure accelerator pedal position
sensor calibration has been learned by ECM. If
not done, possible DTC's may be set.
(8) Use DRB scan tool to erase any stored compan-
ion DTC's from PCM.
POWERTRAIN CONTROL
MODULE
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 OPERATION

As input signals to the Powertrain Control Module
(PCM) change, the PCM adjusts its response to the
output devices. For example, the PCM must calculate
different injector pulse width and ignition timing for
idle than it does for wide open throttle (WOT).
The PCM will operate in two different modes:
Open Loop and Closed Loop.
BR/BE
4mm SDABM4