See TRANSMISSION under MISCELLANEOUS CONTROLS.
Transmission Speed Sensor (A/T Models)
See TRANSMISSION under MISCELLANEOUS CONTROLS.
Transmission Temperature Sensor (A/T Models)
See TRANSMISSION under MISCELLANEOUS CONTROLS.
Water-In-Fuel (WIF) Sensor
Water-in-fuel sensor is located in bottom of fuel
filter/water separator. Testing information not available from
manufacturer.
SWITCHES
Brake Switch
1) Remove lower panel for access to brake switch. Brake
switch is located on bracket, near top of brake pedal. Disconnect
electrical connector from brake switch. Pull plunger on brake switch
fully outward. See Fig. 2.
2) Using ohmmeter, check for continuity between terminals No.
5 and 6 on brake switch. See Fig. 2. Continuity should exist. If
continuity exists, go to next step. If continuity does not exist,
replace brake switch.
3) Push plunger on brake switch fully inward. Using ohmmeter,
check for continuity between terminals No. 1 and 2, and 3 and 4 on
brake switch. See Fig. 2. Continuity should exist. If continuity does
not exist, replace brake switch.
Fig. 2: Identifying Brake Switch Terminals
Courtesy of Chrysler Corp.
Park/Neutral Switch (A/T Models)
See TRANSMISSION under MISCELLANEOUS CONTROLS.
TRUCKS & RWD VANS article.
Transmission Governor Pressure Sensor (A/T Models)
Transmission governor pressure sensor is located on
transmission valve body. If problem exists in transmission governor
pressure sensor or wiring circuit, a Diagnostic Trouble Code (DTC)
will be stored in Powertrain Control Module (PCM). See appropriate
governor pressure sensor test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD
VANS article.
Transmission Overdrive Solenoid (A/T Models)
Transmission overdrive solenoid may also be referred to as
overdrive solenoid or 3-4 solenoid. Transmission overdrive solenoid is
located transmission valve body. If problem exists in transmission
overdrive solenoid or wiring circuit, a Diagnostic Trouble Code (DTC)
will be stored in Powertrain Control Module (PCM). See DTC P1740: TCC
OR O/D SOLENOID PERFORMANCE test in SELF-DIAGNOSTICS - JEEP, TRUCKS &
RWD VANS article.
Transmission Relay (A/T Models)
See RELAYS under RELAYS & SOLENOIDS.
Transmission Speed Sensor (A/T Models)
Transmission speed sensor may also be referred to as
transmission output shaft speed sensor. Transmission speed sensor is
located on overdrive case at rear of transmission. Transmission speed
sensor contains a 2-pin connector with a Dark Blue/Black wire and a
Light Green/Black wire. If problem exists in transmission speed sensor
or wiring circuit, a Diagnostic Trouble Code (DTC) will be stored in
Powertrain Control Module (PCM). See DTC P0720: LOW OUTPUT SPEED
SENSOR RPM, ABOVE 15 MPH test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD
VANS article.
Transmission Temperature Sensor (A/T Models)
Transmission temperature sensor is incorporated into governor
pressure sensor on transmission valve body. If problem exists in
transmission temperature sensor or wiring circuit, a Diagnostic
Trouble Code (DTC) will be stored in Powertrain Control Module (PCM)\
.
See appropriate transmission temperature sensor test in SELF-
DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
Transmission Torque Converter Clutch Solenoid (A/T Models)
The transmission Torque Converter Clutch (TCC) solenoid is
located on transmission valve body. If problem exists in TCC solenoid
or wiring circuit, a Diagnostic Trouble Code (DTC) will be stored in
Powertrain Control Module (PCM). See DTC P0743: TORQUE CONVERTER
CLUTCH SOLENOID/TRANSMISSION RELAY CIRCUIT test in SELF-DIAGNOSTICS -
JEEP, TRUCKS & RWD VANS article.
I - S YSTE M /C O M PO NEN T T E STS - R W D - G ASO LIN E
1999 D odge P ic ku p R 1500
1999 ENGINE PERFORMANCE
CHRY - System & Component Testing - Trucks & RWD Vans - Gas
Dodge: Dakota, Durango, Ram Pickup, Ram Van, Ram Wagon
Jeep Cherokee, Grand Cherokee, Wrangler
INTRODUCTION
Before testing individual components or systems, perform
procedures in BASIC DIAGNOSTIC PROCEDURES - TRUCKS & RWD VANS -
GASOLINE article. Since many computer controlled and monitored
components set a fault message if they malfunction, also perform
procedures in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
NOTE: Testing of individual components does not isolate possible
shorts or opens in wiring harness of electronically
controlled systems. Perform all voltage tests using a Digital
Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance\
unless otherwise instructed in procedure. Use an ohmmeter to
isolate wiring harness shorts or opens.
COMPUTERIZED ENGINE CONTROLS
POWERTRAIN CONTROL MODULE (PCM)
PCM power and ground circuits may be checked by performing
TEST NS-1 in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article. For
PCM location, see PCM LOCATION table.
PCM LOCATION
\
\
\
\
\
\
\
Application Location
Dakota & Durango ................. Right Front Fender, Near Firewall
Ram Pickup, Ram Van & Ram Wagon ...... On Firewall, Near Wiper Motor
\
\
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\
\
ENGINE SENSORS, SOLENOIDS & SWITCHES
SENSORS
Camshaft Position (CMP) Sensor
See appropriate DTC P0340: NO CAM SIGNAL AT PCM test in SELF-
DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
Crankshaft Position (CKP) Sensor
See appropriate DTC P0320: NO CRANK REFERENCE SIGNAL AT PCM
test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
Engine Coolant Temperature (ECT) Sensor
See appropriate DTC P0117: ECT SENSOR VOLTAGE TOO LOW and DTC
P0118: ECT SENSOR VOLTAGE TOO HIGH tests in SELF-DIAGNOSTICS - JEEP,
TRUCKS & RWD VANS article.
Heated Oxygen Sensor (HO2S)
See appropriate DTC for oxygen sensor in SELF-DIAGNOSTICS -
JEEP, TRUCKS & RWD VANS article.
Intake Air Temperature (IAT) Sensor
See appropriate DTC P0112: IAT SENSOR VOLTAGE LOW and DTC
P0113: IAT SENSOR VOLTAGE HIGH tests in SELF-DIAGNOSTICS - JEEP,
TRUCKS & RWD VANS article.
Manifold Absolute Pressure (MAP) Sensor
See appropriate DTC P0107: MAP SENSOR VOLTAGE TOO LOW and DTC
P0108: MAP SENSOR VOLTAGE TOO HIGH tests in SELF-DIAGNOSTICS - JEEP,
TRUCKS & RWD VANS article.
Transmission Temperature (TRANS Temp) Sensor
See appropriate DTC P0711: TRANSMISSION TEMPERATURE SENSOR,
NO TEMPERATURE RISE AFTER START, DTC P0712: TRANSMISSION TEMPERATURE
SENSOR VOLTAGE TOO LOW, and DTC P0713: TRANSMISSION TEMPERATURE SENSOR
VOLTAGE TOO HIGH tests in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS
article.
Throttle Position (TP) Sensor
See appropriate DTC P0122: THROTTLE POSITION SENSOR VOLTAGE
LOW and DTC P0123: THROTTLE POSITION SENSOR VOLTAGE HIGH tests in
SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
Vehicle Speed Sensor (VSS)
See appropriate DTC P0500: NO VEHICLE SPEED SENSOR SIGNAL
test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
SOLENOIDS
Evaporative (EVAP) Purge Solenoid
See appropriate DTC P0443: EVAP PURGE SOLENOID CIRCUIT test
in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
Leak Detection Pump (LDP) Solenoid
See appropriate DTC P1495: LEAK DETECTION PUMP SOLENOID
CIRCUIT test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
Speed Control (S/C) Solenoid
See appropriate DTC P1595: SPEED CONTROL SOLENOID CIRCUITS
test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
Transmission Governor Pressure Solenoid
See appropriate DTC P0748: GOVERNOR PRESSURE
SOLENOID/TRANSMISSION RELAY CIRCUITS test in SELF-DIAGNOSTICS - JEEP,
TRUCKS & RWD VANS article.
Transmission 3-4 Solenoid
See appropriate DTC P0783: TRANSMISSION 3-4 SHIFT SOLENOID,
NO RPM DROP AT 3-4 SHIFT test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD
VANS article.
SWITCHES
Leak Detection Pump (LDP) Switch
See appropriate DTC P1494: LEAK DETECTION PUMP SWITCH OR
MECHANICAL FAULT test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS
article.
Park/Neutral (P/N) Switch
See appropriate DTC P1899: PARK/NEUTRAL SWITCH STUCK IN PARK
OR IN GEAR test in SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.
Power Steering (PS) Switch
See appropriate DTC P0551: POWER STEERING SWITCH FAILURE test
Check the following:
* Check secondary ignition system
* Check engine vacuum
* Check fuel pressure
* Check Engine Coolant Temperature (ECT) sensor calibration
* Check Throttle Position (TP) sensor calibration
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check Idle Air Control (IAC) motor operation
* Check engine mechanical condition
* Check evaporative system
* Check EGR system
* Check coolant temperature sensor and connector
* Check Intake Air Temperature (IAT) sensor calibration
STARTS BUT STALLS
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check fuel pressure
* Check Engine Coolant Temperature (ECT) sensor calibration
* Check Throttle Position (TP) sensor calibration
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check Idle Air Control (IAC) motor operation
HESITATION OR STUMBLE
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check engine vacuum
* Check fuel pressure
* Check Engine Coolant Temperature (ECT) sensor calibration
* Check Throttle Position (TP) sensor calibration
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check oxygen sensor switching
* Check oxygen sensor heater
* Check Idle Air Control (IAC) motor operation
* Check engine mechanical condition
* Check evaporative system
* Check EGR system
* Check Intake Air Temperature (IAT) sensor calibration
* Check Park/Neutral Position (PNP) switch.
SURGING
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check engine vacuum
* Check fuel pressure
* Check Engine Coolant Temperature (ECT) sensor calibration
* Check Throttle Position (TP) sensor calibration
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check oxygen sensor switching
* Check Idle Air Control (IAC) motor operation
* Check evaporative system.
LACK OF POWER
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check fuel pressure
* Check Engine Coolant Temperature (ECT) sensor calibration
* Check Throttle Position (TP) sensor calibration
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check oxygen sensor switching
* Check Idle Air Control (IAC) motor operation
* Check EGR system.
KNOCKING
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check fuel pressure
* Check Engine Coolant Temperature (ECT) sensor calibration
* Check Throttle Position (TP) sensor calibration
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check oxygen sensor switching
* Check Idle Air Control (IAC) motor operation
* Check evaporative system.
ENGINE MISFIRE
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check fuel pressure
* Check minimum idle airflow
* Check oxygen sensor switching
* Check Idle Air Control (IAC) motor operation
* Check EGR system.
BACKFIRE
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check fuel pressure
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check oxygen sensor switching
* Check EGR system.
ROUGH OR ERRATIC IDLE
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check engine vacuum
* Check fuel pressure
* Check Engine Coolant Temperature (ECT) sensor calibration
* Check Throttle Position (TP) sensor calibration
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check oxygen sensor switching
* Check oxygen sensor heater
* Check Idle Air Control (IAC) motor operation
* Check engine mechanical condition
* Check evaporative system
* Check EGR system
* Check Intake Air Temperature (IAT) motor operation
* Check Park/Neutral Position (PNP) switch.
POOR FUEL ECONOMY
Check the following:
* Check secondary ignition system
* Check PCM power and ground circuits
* Check engine vacuum
* Check fuel pressure
* Check Engine Coolant Temperature (ECT) sensor calibration
* Check Throttle Position (TP) sensor calibration
* Check Manifold Absolute Pressure (MAP) calibration
* Check minimum idle airflow
* Check oxygen sensor switching
* Check oxygen sensor heater
* Check Idle Air Control (IAC) motor operation
* Check engine mechanical condition
* Check evaporative system
* Check EGR system
* Check Intake Air Temperature (IAT) motor operation
* Check Park/Neutral Position (PNP) switch.
INTERMITTENTS
INTERMITTENT PROBLEM DIAGNOSIS
Intermittent fault testing requires duplicating circuit or
component failure to identify the problem. These procedures may lead
to PCM setting a Diagnostic Trouble Code (FTC) which may help in
diagnosis.
If problem vehicle does not produce FTC, monitor voltage or
resistance values using a DVOM while attempting to reproduce
conditions causing intermittent fault. A status change on DVOM
indicates a fault has been located.
Use a DVOM to pinpoint faults. When monitoring voltage,
ensure ignition switch is in ON position or engine is running. Ensure
ignition switch is in OFF position or negative battery cable is
disconnected when monitoring circuit resistance. Status changes on
DVOM during test procedures indicate area of fault.
TEST PROCEDURES
Intermittent Simulation
To reproduce the conditions creating an intermittent fault,
use the following methods:
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. 2. 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. See Fig. 3. CCD Bus circuits connect the
various vehicle control modules. These circuits are connected between
ECM and PCM to allow communication between modules. Inputs and outputs
are at each module.
Fig. 3: Locating Powertrain Control Module (PCM)
Courtesy of Chrysler Corp.
ENGINE CONTROL MODULE (ECM)
Engine Control Module (ECM) uses input signals from various
switches and sensors to control output devices in order to achieve
optimum engine performance for all operating conditions. Components
are grouped into 2 categories. The first category covers INPUT
DEVICES, which control or produce voltage signals monitored by the
ECM. The second category covers OUTPUT SIGNALS, which are components
controlled by the ECM. See ECM INPUT DEVICES and ECM OUTPUT SIGNALS.
POWERTRAIN CONTROL MODULE (PCM)
Powertrain Control Module (PCM) is a preprogrammed, dual
microprocessor digital computer which does not directly regulate or
control diesel fuel system operation, but does operate or control the
following systems:
* A/C System Operation
* Automatic Shutdown (ASD) Relay
* Certain Transmission Shift Features (A/T Only)
* Certain Warning Lights