1999 DODGE RAM wiring

WAIT-TO-START Warning Light
WAIT-TO-START warning light is located on instrument panel,
just below the speedometer. WAIT-TO-START warning light will come on
for a short period and then go off as a bulb and wiring circuit test
each time ignition switch is turned to the ON position. If Engine
Control Module (ECM) determines intake manifold air temperature is
less than 59
F (15C) by input signal received from intake manifold
air temperature sensor, ECM delivers output signal to operate WAIT-TO-
START warning light and intake manifold air heater for a preheat
cycle.
WAIT-TO-START warning light will remain on until intake
manifold air heater preheat cycle is complete. WAIT-TO-START warning
light will flash on and off if intake manifold air temperature sensor
signal to ECM is not within a specified value and Diagnostic Trouble
Code (FTC) will be stored in ECM memory.
WATER-IN-FUEL Warning Light
WATER-IN-FUEL warning light is located on instrument panel,
just below tachometer. WATER-IN-FUEL warning light will come on for a
short period and then go off as a bulb and wiring circuit test each
time ignition switch is turned to the ON position. If Engine Control
Module (ECM) determines water exists in fuel/water separator by input
signal from Water-In-Fuel (WIF) sensor, ECM will deliver output signal\
to turn on the WATER-IN-FUEL warning light.
ECM/PCM OUTPUT SIGNALS
A/C Clutch Relay
The Engine Control Module (ECM) controls A/C compressor
operation by controlling ground circuit for A/C clutch relay. ECM de-
energizes A/C clutch relay if engine coolant temperature is more than
257
F (125C). The A/C clutch relay is located in power distribution
center at driver's side front corner of engine compartment, near the
battery.
Automatic Shutdown (ASD) Relay
The Engine Control Module (ECM) controls ASD operation by
controlling ground circuit for ASD relay. ASD provides voltage to
operate generator field control for charging system. ASD relay is
located in power distribution center at driver's side front corner of
engine compartment, near the battery. Automatic Shutdown (ASD) relay
may also be referred to as Auto Shutdown (ASD) relay.
CCD Bus
These circuits are connected between Engine Control Module
(ECM) and Powertrain Control Module (PCM) to allow communication
between modules.
Cruise Control System
Engine Control Module (ECM) regulates cruise control system
operation by controlling vacuum at cruise control servo. Vacuum is
controlled by use of vacuum and vent solenoids in cruise control
servo.
Data Link Connector
Engine Control Module (ECM) provides output information at
Data Link Connector (DLC) when using scan tool to perform various
tests on the ECM and electronic control system. Data link connector is
a 16-pin connector located at lower edge of driver's side of
instrument panel, just above the accelerator pedal.
5-Volt Sensor Supply Output
Powertrain Control Module (PCM) supplies a 5-volt reference

signal to the transmission solenoid assembly for transmission
temperature sensor.
Generator Field
Engine Control Module (ECM) provides output signals to
generator field for regulating charging system voltage at 12.9-15.0
volts. ECM contains an internal electronic voltage regulator for
controlling the charging system voltage.
Generator Light
If Engine Control Module (ECM) senses a low charging system
condition, generator light on instrument panel (if equipped) will be
turned on. Generator light may also come on momentarily at low idle
speed when all accessories are on.
Malfunction Indicator Light (MIL)
The MIL is located on the instrument panel, just below
tachometer and may also be referred to as the CHECK ENGINE light. MIL
comes on for a short period and then goes off as a bulb and wiring
circuit test each time ignition switch is turned to the ON position.
If Engine Control Module (ECM) receives an incorrect signal or
receives no signal from certain sensors or components, ECM will turn
on the MIL to warn the driver that a malfunction exists in the
electronic system.
Overdrive Indicator Light (A/T Models)
Engine Control Module (ECM) delivers output signal to operate\
transmission overdrive indicator (O/D OFF) light in accordance with
position of the transmission overdrive switch. If overdrive is turned
off with transmission overdrive switch, transmission overdrive
indicator light will be turned on. Transmission overdrive indicator
light is located on instrument panel, just below the speedometer.
Tachometer
Engine Control Module (ECM) delivers output signal to operate\
tachometer on instrument panel to indicate engine RPM.
Transmission Overdrive Solenoid (A/T Models)
Engine Control Module (ECM) delivers output signal to
transmission overdrive solenoid for controlling transmission overdrive
shifts. Transmission overdrive solenoid is located on transmission
valve body.
Transmission Relay (A/T Models)
Transmission relay may be referred to as transmission control
relay or transmission 12-volt supply relay. Transmission relay ground
circuit is controlled by the Engine Control Module (ECM). When ground
circuit is completed, transmission relay supplies voltage to solenoid
assembly on the transmission. Transmission relay is located in power
distribution center at driver's side front corner of engine
compartment, near the battery.
Transmission Temperature Warning Light (A/T Models With
Heavy-Duty Transmission)
Engine Control Module (ECM) delivers output signal to turn on\
transmission temperature warning light if transmission fluid
temperature is determined to be greater than 280
F (138C) by the
transmission temperature sensor. Transmission temperature warning
light is located on instrument panel, just below the tachometer.
Transmission Torque Converter Clutch Solenoid (A/T Models)
Engine Control Module (ECM) delivers an output signal to
operate transmission torque converter clutch solenoid for torque

using DLC and a scan tool. The DLC also provides a means to
communicate with various vehicle control modules, check system
operating conditions and to operate various system components.
MALFUNCTION INDICATOR LIGHT (MIL)
The MIL is located on the instrument panel, just below
tachometer and may also be referred to as the CHECK ENGINE light. MIL
comes on for a short period and then goes off as a bulb and wiring
circuit test each time ignition switch is turned to the ON position.
If Engine Control Module (ECM) receives an incorrect signal or
receives no signal from certain sensors or components, ECM will turn
on the MIL to warn the driver that a malfunction exists in the
electronic system.
MISCELLANEOUS CONTROLS
TRANSMISSION
Transmission Overdrive Solenoid (A/T Models)
Engine Control Module (ECM) operates transmission overdrive
solenoid for controlling transmission overdrive shifts. Transmission
overdrive solenoid is located on transmission valve body.
Transmission Torque Converter Clutch Solenoid (A/T Models)
Engine Control Module (ECM) operates transmission torque
converter clutch solenoid for torque converter lock-up. ECM uses
various input signals such as transmission temperature, output shaft
speed, central module timer, engine speed, APPS and brake switch
position to determine operation of transmission torque converter
clutch solenoid. Torque converter clutch solenoid is located on
transmission valve body.


E - T H EO RY/O PER ATIO N - R W D - G ASO LIN E

1999 D odge P ic ku p R 1500
1999 ENGINE PERFORMANCE
CHRY - Theory & Operation - Trucks & RWD Vans - Gasoline
Dakota, Durango, Ram Pickup, Ram Van, Ram Wagon
INTRODUCTION
This article covers the basic description and operation of
engine performance related systems and components. Read this article
before working on unfamiliar systems.
COMPUTERIZED ENGINE CONTROLS
POWERTRAIN CONTROL MODULE (PCM)
The PCM is a digital computer that controls ignition timing,
air/fuel ratio, fuel injector pulse width, ignition coil(s), spark
advance, emission control devices, cooling fan, charging system, idle
speed, cruise control (if equipped), fuel pump and tachometer. For PCM\
location, see PCM LOCATION. PCM uses data from various input sources
to control output devices in order to achieve optimum engine
performance for all operating conditions.
PCM has voltage converters that convert battery voltage to
regulated 5-volt output. The 5-volt output powers battery temperature
sensor, Camshaft Position (CMP) sensor on models equipped with
Distributorless Ignition System (DIS) or distributor on models without\
DIS, Crankshaft Position (CKP) sensor, Engine Coolant Temperature
(ECT) sensor, Intake Air Temperature (IAT) sensor, logic circuits,
Manifold Absolute Pressure (MAP) sensor, Throttle Position (TP) sens\
or
and Vehicle Speed Sensor (VSS) on some models.
PCM LOCATION









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Application Location
Dakota & Durango ................. Right Front Fender, Near Firewall
Ram Pickup, Ram Van & Ram Wagon .... On Firewall, Near Wiper Motor









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NOTE: Components are grouped into 2 categories. The first category,
INPUT DEVICES, includes components that control or produce
voltage signals monitored by the PCM. The second category,
OUTPUT SIGNALS, includes components controlled by the PCM
(this is accomplished by the PCM grounding individual
circuits).
INPUT DEVICES
Vehicles are equipped with different combinations of input
devices. Not all devices are used on all models. To determine
component location and input usage on a specific model, see
appropriate wiring diagram in WIRING DIAGRAMS article. Available input
signals include:
A/C Switch
Switch signals PCM that A/C has been selected. PCM then
activates A/C compressor clutch relay and maintains idle speed at a
preprogrammed RPM. This is done through control of Idle Air Control

Power Steering Pressure Switch
On 2.5L Dakota only, power steering pressure switch sends a
signal to PCM. PCM will raise idle speed to prevent stalling during
high power steering pressure (375-575 psi), low RPM conditions.
Serial Communication Interface (SCI) Receive
SCI receive circuit is a serial communication link used when
diagnosing vehicle using scan tool. PCM receives data and device
activation commands from scan tool on this circuit.
Throttle Position (TP) Sensor
TP sensor monitors opening angle of throttle blade. TP sensor
will vary output voltage from about .26 volt at minimum throttle
opening (idle), to about 4.5 volts at Wide Open Throttle (WOT). PCM
uses this information and other sensor inputs to determine engine
operation. In response, PCM will adjust fuel injection pulse width and
ignition timing.
Transmission Governor Pressure Sensor (A/T Models)
Sensor sends PCM a signal indicating governor pressure. PCM
uses signal as feedback for governor solenoid control.
Transmission Overdrive/Override (OD/OR) Switch (A/T Models)
On models with Overdrive (OD), PCM regulates 3-4 OD upshift
and downshift through OD solenoid. Transmission OD/OR switch is
mounted in instrument panel.
OD/OR switch is normally closed. If OD/OR switch is depressed
and it opens, transmission will not enter OD. Transmission will
downshift if it is in OD and OD/OR switch is depressed.
OD/OR switch circuit includes a transmission fluid
temperature sensor. If this sensor opens, transmission will not shift
into overdrive, or will downshift if already in overdrive.
Transmission Temperature Sensor (A/T Models)
Transmission temperature sensor monitors transmission fluid
temperature and sends an input signal to PCM. Input signal is used for
controlling torque converter clutch operation, overdrive shifts, low
temperature shift compensation, wide open throttle shift strategy and
governor pressure. Transmission temperature sensor is located in
transmission valve body, incorporated into governor pressure sensor.
If transmission fluid temperature is more than 260
F (126C),
PCM forces a 4-3 downshift and engages torque converter clutch until
fluid cools. Once fluid cools to less than 230
F (110C), PCM allows a
3-4 shift. PCM prevents torque converter clutch engagement and
overdrive operation when fluid temperature is less than 50
F (10C).
Vehicle Speed Sensor (VSS)
VSS generates 8 pulses per sensor revolution. VSS input is
used by PCM to determine vehicle speed and distance traveled, and to
maintain set speed during cruise control operation.
PCM interprets speed sensor input along with TP sensor closed
throttle input. This enables PCM to determine if a closed throttle
deceleration or normal throttle idle (vehicle stopped) condition
exists. During deceleration, PCM controls IAC motor to maintain a
desired MAP value. During idle (vehicle stopped), PCM controls IAC
motor to maintain a desired idle speed.
OUTPUT SIGNALS
NOTE: Each vehicle may be equipped with different combinations of
computer-controlled components. The following components may
NOT be used on all models. To determine component location
and output usage on a specific model, see appropriate wiring

diagram in appropriate WIRING DIAGRAMS article. For theory
and operation on each output component, refer to indicated
system.
A/C Clutch Relay
See A/C CLUTCH RELAY under MISCELLANEOUS CONTROLS.
Auto Shutdown (ASD) Relay
See AUTO SHUTDOWN (ASD) RELAY & FUEL PUMP RELAY under
MISCELLANEOUS CONTROLS.
Distributorless Ignition System (DIS)
See DISTRIBUTORLESS IGNITION SYSTEM (DIS) under IGNITION
SYSTEM.
Evaporative Canister Purge Control Solenoid (EVAP-CPCS)
See EVAPORATIVE (EVAP) EMISSIONS SYSTEM under EMISSION
SYSTEMS.
Fuel Injectors
See FUEL CONTROL under FUEL SYSTEM.
Fuel Pump Relay
See AUTO SHUTDOWN (ASD) RELAY & FUEL PUMP RELAY under
MISCELLANEOUS CONTROLS.
Generator
See GENERATOR under MISCELLANEOUS CONTROLS.
Idle Air Control (IAC) Motor
See IDLE SPEED under FUEL SYSTEM.
Ignition Coil
See IGNITION SYSTEM.
In-Tank Fuel Pump
See FUEL DELIVERY under FUEL SYSTEM.
Limp-In Mode
See LIMP-IN MODE under MISCELLANEOUS CONTROLS.
Malfunction Indicator Light (MIL)
See MALFUNCTION INDICATOR LIGHT under SELF-DIAGNOSTIC SYSTEM.
Radiator Fan Relay
See RADIATOR FAN RELAY under MISCELLANEOUS CONTROLS.
Serial Communications Interface (SCI) Transmit
See SERIAL COMMUNICATIONS INTERFACE (SCI) under SELF-
DIAGNOSTIC SYSTEM.
Shift Indicator Light
See SHIFT INDICATOR LIGHT under MISCELLANEOUS CONTROLS.
Speed Control Servo
See SPEED CONTROL SERVO under MISCELLANEOUS CONTROLS.
Tachometer
See TACHOMETER under MISCELLANEOUS CONTROLS.
Torque Converter Clutch (TCC) Solenoid
See TORQUE CONVERTER CLUTCH (TCC) SOLENOID under
MISCELLANEOUS CONTROLS.

TR AN SM IS SIO N R EM OVA L & IN STA LLA TIO N

1999 D odge P ic ku p R 1500
1998-99 TRANSMISSION SERVICING
CHRY - Trans Removal & Installation - Trucks & RWD Vans
Dakota, Ram Pickup, Ram Van/Wagon
WARNING: 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.
MANUAL TRANSMISSION
NOTE: For manual transmission replacement procedures, see
appropriate article in CLUTCHES.
AUTOMATIC TRANSMISSION
DAKOTA & DURANGO
Removal
1) Disconnect negative battery cable. Raise and support
vehicle. Disconnect and remove necessary skid plates and exhaust
components for transmission removal. Remove engine-to-transmission
struts (if equipped). These struts are located between front of
transmission and engine.
2) Ensure area around transmission oil cooler lines fitting
are clean. Disengage retainer on quick-disconnect cooler line fitting.
Pull cooler line from transmission oil cooler.
CAUTION: Crankshaft position sensor must be removed from transmission
housing before removing transmission to prevent damage to
crankshaft position sensor.
3) Remove starter. Disconnect electrical connector for
crankshaft position sensor. On 2.5L, crankshaft position sensor is
mounted on driver's side of transmission housing. See Fig. 1. On 3.9L,
5.2L and 5.9L, crankshaft position sensor is mounted on passenger's
side of transmission housing. See Fig. 2.
4) Remove crankshaft position sensor bolts or nuts. Remove
crankshaft position sensor from transmission housing. Remove dipstick,
dipstick tube and "O" ring from transmission.
5) Remove torque converter cover. Place reference mark on
flexplate and torque converter for installation reference. Rotate
crankshaft clockwise and remove torque converter bolts.
6) Place reference mark on drive shaft flanges for
installation reference. Remove drive shaft from transmission. On 4WD
models, disconnect drive shaft from transfer case. Disconnect shift
rod for transfer case from transfer case shift lever.
7) On all models, disconnect necessary control cables, wiring
harnesses, and shift linkage or cable from transmission. Support rear
of engine with jack stand. Using transmission jack, slightly raise
transmission to release pressure from rear mount and rear crossmember.
8) Remove bolts securing rear support and rear mount to
transmission and rear crossmember. Raise transmission slightly. Slide
exhaust hanger arm from bracket on rear support. Remove rear support
and rear mount.
9) Remove rear crossmember located below the transmission. On
4WD models, disconnect electrical connectors from transfer case. On

Courtesy of Chrysler Corp.
Installation
1) To install, reverse removal procedure. Ensure torque
converter is fully seated in transmission by measuring distance from
cylinder block surface on transmission housing to front edge on torque
converter bolt lug on front of torque converter. Distance should be .
50" (12.7 mm) if torque converter is fully seated.
CAUTION: Proper length torque converter bolts must be used. If
replacing any torque converter bolts, ensure proper length
bolt is used.
2) Tighten bolt/nuts to specification. See TORQUE
SPECIFICATIONS. Ensure reference mark on torque converter and
flexplate, and drive shaft flanges are aligned. Adjust shift cable or
linkage, throttle valve cable and transfer case shift linkage if
necessary. See AUTOMATIC TRANSMISSION - TRUCKS & RWD VANS article.
3) Use NEW "O" ring when installing dipstick tube. Before
installing oil cooler lines on transmission, ensure all fittings are
clean. Install oil cooler line into quick-disconnect fitting. Push oil
cooler line inward until a click is heard. Pull on oil cooler line to
ensure oil cooler line is locked in place. Fill transmission with
Mopar ATF Plus Type 7176.
RAM PICKUP
Removal
1) Disconnect negative battery cable. Raise and support
vehicle. Disconnect and remove necessary skid plates and exhaust
components for transmission removal. Remove engine-to-transmission
struts (if equipped). These struts are located between front of
transmission and engine.
2) Ensure area around transmission oil cooler lines fitting
are clean. Disengage retainer on quick-disconnect cooler line fitting.
Pull cooler line from transmission oil cooler. Remove starter.
CAUTION: On 3.9L, 5.2L and 5.9L gasoline models, crankshaft position
sensor must be removed from transmission housing before
removing transmission to prevent damage to crankshaft
position sensor.
3) On 3.9L, 5.2L and 5.9L gasoline models, disconnect
electrical connector for crankshaft position sensor. Crankshaft
position sensor is mounted on passenger's side of transmission
housing. See Fig. 2.
4) Remove crankshaft position sensor bolts. Remove crankshaft
position sensor from transmission housing. Remove dipstick, dipstick
tube and "O" ring from transmission.
5) Remove torque converter cover. Place reference mark on
flexplate and torque converter for installation reference. Rotate
crankshaft clockwise and remove torque converter bolts.
6) Place reference mark on drive shaft flanges for
installation reference. Remove drive shaft from transmission. On 4WD
models, disconnect drive shaft from transfer case. Disconnect shift
rod for transfer case from transfer case shift lever.
7) On all models, disconnect necessary control cables, wiring
harnesses, and shift linkage from transmission. Support rear of engine
with jack stand. Using transmission jack, slightly raise transmission
to release pressure from rear mount and rear crossmember.
8) Remove bolts securing rear support and rear mount to
transmission and rear crossmember. Raise transmission slightly. Slide
exhaust hanger arm from bracket on rear support. Remove rear support