ECU DODGE RAM 1999 Service Manual Online

Fig. 1: Identifying Typical Transfer Case Shift Linkage Components
Courtesy of Chrysler Corp.
Ram Pickup
1) Place transfer case shift lever in 2H position. Use wire
or bungie cord to secure transfer case shift lever in 2H position.
2) Raise and support vehicle. Loosen lock bolt at adjusting
swivel on shift rod. See Fig. 1. Ensure shift rod slides freely in
adjusting swivel. If shift rod fails to slide freely in adjusting
swivel, lubricate shift rod as necessary.
3) Ensure shift lever on transfer case is still in 2H
position. Lower vehicle. Position shift lever so that distance from
instrument panel to 2H position dot in shift lever insert is 5.75 in.
(146.000 mm). Tighten lock bolt to 90 INCH lbs. (10 N.m). Check shif\
t
linkage operation.

3800 engines were suffering from exactly this. The point is that a
lack of detail could cause misdiagnosis.
As you might have guessed, a lab scope would not miss this.
RELATIONSHIP BETWEEN DWELL & DUTY CYCLE READINGS TABLE (1)









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Dwell Meter (2) Duty Cycle Meter
1
.................................................... 1%
15 .................................................. 25%
30 .................................................. 50%
45 .................................................. 75%
60 ................................................. 100%
( 1) - These are just some examples for your understanding.
It is okay to fill in the gaps.
( 2) - Dwell meter on the six-cylinder scale.









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THE TWO TYPES OF INJECTOR DRIVERS
OVERVIEW
There are two types of transistor driver circuits used to
operate electric fuel injectors: voltage controlled and current
controlled. The voltage controlled type is sometimes called a
"saturated switch" driver, while the current controlled type is
sometimes known as a "peak and hold" driver.
The basic difference between the two is the total resistance
of the injector circuit. Roughly speaking, if a particular leg in an
injector circuit has total resistance of 12 or more ohms, a voltage
control driver is used. If less than 12 ohms, a current control driver
is used.
It is a question of what is going to do the job of limiting
the current flow in the injector circuit; the inherent "high"
resistance in the injector circuit, or the transistor driver. Without
some form of control, the current flow through the injector would
cause the solenoid coil to overheat and result in a damaged injector.
VOLTAGE CONTROLLED CIRCUIT ("SATURATED SWITCH")
The voltage controlled driver inside the computer operates
much like a simple switch because it does not need to worry about
limiting current flow. Recall, this driver typically requires injector
circuits with a total leg resistance of 12 or more ohms.
The driver is either ON, closing/completing the circuit
(eliminating the voltage-drop), or OFF, opening the circuit (causing \
a
total voltage drop).
Some manufacturers call it a "saturated switch" driver. This
is because when switched ON, the driver allows the magnetic field in
the injector to build to saturation. This is the same "saturation"
property that you are familiar with for an ignition coil.
There are two ways "high" resistance can be built into an
injector circuit to limit current flow. One method uses an external
solenoid resistor and a low resistance injector, while the other uses
a high resistance injector without the solenoid resistor. See the left
side of Fig. 1.
In terms of injection opening time, the external resistor
voltage controlled circuit is somewhat faster than the voltage
controlled high resistance injector circuit. The trend, however, seems
to be moving toward use of this latter type of circuit due to its
lower cost and reliability. The ECU can compensate for slower opening

Ram Van & Ram Wagon
1) Place window glass halfway between up and down positions.
Verify glass can be moved slightly from side to side, front to rear,
and up and down. If glass does not move freely, check window glass,
tracks and regulator for sticking or binding. Repair as necessary and
recheck system operation. If glass moves freely, go to next step.
2) Disconnect negative battery cable. Disconnect and remove
power window switch in door with inoperative window. See POWER WINDOW
SWITCH under REMOVAL & INSTALLATION. Connect negative battery cable.
Turn ignition on. Measure voltage between passenger power window
switch wiring harness connector terminal (Tan wire) or driver power
window switch wiring harness connector terminal (Tan wire) and ground.\
See WIRING DIAGRAMS. If battery voltage is not present, repair open
Tan wire as necessary. If battery voltage exists, and inoperative
window is on driver side, go to step 4). If battery voltage exists,
and inoperative window is on passenger side, go to next step.
NOTE: Passenger's power window switch is grounded through driver's
power window switch.
3) Disconnect negative battery cable. Check continuity
between ground and passenger's power window switch harness connector
terminals No. 2 (Brown/White wire) and No. 4 (Violet/White wire). Se\
e
WIRING DIAGRAMS. If continuity exists on both circuits, go to step 5).
If continuity does not exist on either or both circuits, repair open
circuit.
4) Check power window switch. See POWER WINDOW SWITCH under
COMPONENT TESTS. Replace faulty power window switch as necessary. If
switch is okay, go to next step.
5) Using an ohmmeter, check continuity of each circuit
between inoperative power window switch wiring harness connector and
corresponding power window motor wiring harness connector terminal.
See WIRING DIAGRAMS. If continuity does not exist in one or more
circuits, repair open circuit(s) as necessary. Recheck system
operation. If continuity exists in all circuits, power window switch
and switch circuits are okay. Check power window motor. See POWER
WINDOW MOTOR under COMPONENT TESTS.
REMOVAL & INSTALLATION
CAUTION: When battery is disconnected, vehicle computer and memory
systems may lose memory data. Driveability problems may exist
until computer systems have completed a relearn cycle. See
COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION
before disconnecting battery.
DOOR TRIM PANEL
Removal & Installation (Caravan, Town & Country, & Voyager)
1) Using a trim stick, pry courtesy light from door trim.
Disconnect courtesy light connector. Remove door assist handle (if
equipped). Remove door pull cup (if equipped). Remove screws attachin\
g
trim panel to door below map pocket (if equipped). Using a trim stick,\
remove screw cover from switch panel.
2) Remove screws securing switch panel to door trim and
remove panel. Using a trim stick, remove seat/mirror memory switch (if
equipped). Remove screw securing door trim to door panel from behind
inside latch release handle.
3) Disengage clips holding door trim to door frame around
perimeter of panel. Tilt top of trim panel away from door to gain
access to latch linkage. Disengage clip holding linkage rod to inside
latch release handle. Separate linkage rod from latch handle. Remove

door trim panel. To install, reverse removal procedure.
Removal & Installation (Dakota & Durango)
Lower window to full down position, if possible. Remove
screws attaching trim panel to door. Lift panel up and outward to
release retainers. Disconnect door handle linkage and all wiring.
remove trim panel. To install, reverse removal procedure.
Removal & Installation (Ram Pickup)
Lower window to full down position, if possible. Remove
screws attaching trim panel to door. Remove window switch. Using trim
tool, disconnect clips around edge of door. Lift panel up and outward
to release retainers. Disconnect door handle linkage and all wiring.
remove trim panel. To install, reverse removal procedure.
Removal & Installation (Ram Van & Ram Wagon)
Remove screw attaching trim panel pull cup to door. Remove
screw attaching door handle bezel to door. Remove screws attaching
trim panel to door. Using trim tool, disconnect clips around edge of
trim panel. Remove trim panel. To install, reverse removal procedure.
"D" PILLAR TRIM PANEL
Removal & Installation (Caravan, Town & Country, & Voyager -
Left Side)
1) Remove rear header trim cover. Remove liftgate sill plate.
On long wheelbase models, remove second rear seat belt turning loop.
On short wheelbase models, remove bolt securing second rear seat belt
lower anchor to quarter panel.
2) On all models, remove jack storage cover. Remove "D" panel
retaining screws. Using a trim stick, gently pry around perimeter of
"D" pillar trim panel and separate trim panel from inner quarter
panel. Disconnect rear speaker connector (if equipped).
3) On short wheelbase models, pass seat belt through slot in
"D" pillar. On all models, remove "D" pillar trim panel. To install,
reverse removal procedure.
Removal & Installation (Caravan, Town & Country, & Voyager -
Right Side)
1) Remove rear header trim cover. Remove liftgate sill plate.
On long wheelbase models, remove second rear seat belt turning loop.
On short wheelbase models, remove bolt securing second rear seat belt
lower anchor to quarter panel. Remove quarter panel trim bolster.
2) On all models, remove "D" panel retaining screws.
Disengage hidden "D" pillar trim panel clips. Separate "D" pillar trim
panel from "D" pillar. Disconnect rear speaker connector (if
equipped). Remove trim panel. To install, reverse removal procedure.
POWER WINDOW MOTOR
Removal & Installation (Caravan, Town & Country, & Voyager)
1) Disconnect negative battery cable. Remove door trim panel.
See DOOR TRIM PANEL. Remove watershield. Tape window in its existing
position. Cut and discard window motor tie wrap. Disconnect window
motor connector. Remove window motor mounting screws/nuts.
2) Remove window motor and cables from door and allow to hang
from door. Do not remove drum and cables at this time. Install NEW
window motor in door. Tighten screws/nuts to 30-40 INCH lbs. (3.4-4.5
N.m). Remove drum cover plate from faulty window motor. See Fig. 7.
Lift cable guide, drum and cables from motor.
CAUTION: DO NOT allow drum to separate from cable guide, by dropping
drum or letting cables unwind.

Disconnect power vent motor connector. Remove nut securing crank to
vent glass. See Fig. 10. Remove bolts securing power vent motor to "D"
pillar. Remove power vent motor. Remove crank from motor. To install,
cycle motor to open position. Install crank in open position to new
motor. To complete installation, reverse removal procedure.
Fig. 10: Removing Power Vent Motor (Caravan, Town & Country, &
Voyager)
Courtesy of Chrysler Corp.
POWER WINDOW SWITCH
Removal & Installation (Caravan, Town & Country, & Voyager)
Disconnect negative battery cable. Using a trim stick, remove
screw cover from switch panel. Remove screws securing switch panel to
door trim. Disconnect wiring connector. Remove switch assembly from
panel. Remove door lock switch retaining screws. To install, reverse

removal procedure.
Removal & Installation (Ram Van & Ram Wagon)
Disconnect negative battery cable. Remove door trim panel.
See DOOR TRIM PANEL. Remove mirror flag bezel. Remove screws attaching
window switch mounting plate to mirror flag bezel. Using a thin
screwdriver, gently pry snap clips at sides of window switch
receptacle from rear of mounting plate. Pull switch out of receptacle.
To install, reverse removal procedure. Tighten mounting screws to 20
INCH lbs. (2.2 N.m).
Removal & Installation (Dakota & Ram Pickup)
Disconnect negative battery cable. Using a trim stick, gently
pry upper edge of switch bezel to release retainer securing bezel to
door trim panel. Pull switch and bezel away from door trim panel and
disconnect switch wire connector. To install, reverse removal
procedure.
Removal & Installation (Durango)
Disconnect negative battery cable. Remove door trim panel.
See DOOR TRIM PANEL. On driver's door, remove screws from back side of
door trim panel and remove switch and bezel. On passenger's doors,
gently pry snap clips at sides of window switch receptacle on back of
door trim panel switch bezel. On all doors, remove power window switch
from bezel. To install, reverse removal procedure.
WIRING DIAGRAMS