sensor DODGE RAM 2002 Service Service Manual
[x] Cancel search | Manufacturer: DODGE, Model Year: 2002, Model line: RAM, Model: DODGE RAM 2002Pages: 2255, PDF Size: 62.07 MB
Page 387 of 2255
RIGHT SEAT HEATER INOPERATIVE
(1) If a heated seat heats but one or both indicator
lamps (LED's) on the heated seat switch fail to illu-
minate, check the driver circuit with the inoperative
LED for a short to ground. If OK, replace the heated
seat switch. If NOT OK repair the short to ground as
required and than replace the heated seat switch.
NOTE: IF THE RIGHT SEAT CUSHION IS ALREADY
WARM THE FOLLOWING STEP WILL NOT PROVE
CONCLUSIVE.
(2) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #3 for battery voltage when the right heated
seat switch is turned ªONº, voltage should be
present, If OK go to Step 3 If NOT OK, test the right
heated seat switch (Refer to 8 - ELECTRICAL/
HEATED SEATS/PASSENGER HEATED SEAT
SWITCH - DIAGNOSIS AND TESTING). If the
switch tests OK, check for continuity between the
switch and control module on the MUX circuit, If OK
replace the heated seat control module. If NOT OK,
repair the open or shorted MUX circuit as required.
NOTE: BE CERTAIN THE BATTERY IS FULLY
CHARGED BEFORE TESTING. FAILURE TO DO SO
CAN RESULT IN INCORRECT READINGS.
(3) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #10 for battery voltage, while observing the
voltmeter depress the right heated seat switchlow
setting twice, voltage should toggle between
approx.12v and 8v, If OK go to Step 4. If NOT OK
check for continuity between the switch and control
module on the low heat driver circuit, If OK replace
the heated seat control module.
(4) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #11 for battery voltage, while observing the
voltmeter depress the right heated seat switchhigh
setting twice, voltage should toggle between
approx.12v and 8v, If OK go to Step 5. If NOT OK
check for continuity between the switch and control
module on the high heat driver circuit, If OK replace
the heated seat control module.
(5) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #2 for approx. 5v, voltage should be present, If
OK go to Step 6. If NOT OK replace the heated seat
control module.
(6) Back-probe the heated seat module wire har-
ness connector, do not disconnect. Check cavity #7 for
a range in voltage from 1.72v (warm seat) ± 3.0v
(cold seat). It should be within this range, If OK
replace the heated seat module. If NOT OK test theHeated Seat Sensor. If NOT OK, replace the right
heated seat element and sensor assembly. If the
heated seat sensor tests OK, check for continuity
between the right heated seat cushion connector and
control module connector on the 5v supply circuit, If
NOT OK, repair the open or shorted 5v supply circuit
as required. If OK check for continuity between the
right heated seat cushion connector and control mod-
ule connector on the temperature sensor input cir-
cuit. If NOT OK, repair the open or shorted
temperature sensor input circuit as required. If OK
replace the heated seat control module.
LEFT SEAT HEATER INOPERATIVE
(1) If a heated seat heats but one or both indicator
lamps (LED's) on the heated seat switch fail to illu-
minate, check the driver circuit with the inoperative
LED for a short to ground. If OK, replace the heated
seat switch. If NOT OK repair the short to ground as
required and than replace the heated seat switch.
NOTE: IF THE LEFT SEAT CUSHION IS ALREADY
WARM THE FOLLOWING STEP WILL NOT PROVE
CONCLUSIVE.
(2) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #5 for battery voltage when the left heated
seat switch is turned ªONº, voltage should be
present, If OK go to Step 3 If NOT OK, test the left
heated seat switch (Refer to 8 - ELECTRICAL/
HEATED SEATS/DRIVER HEATED SEAT SWITCH
- DIAGNOSIS AND TESTING). If the switch tests
OK, check for continuity between the switch and con-
trol module on the MUX circuit, If OK replace the
heated seat control module. If NOT OK, repair the
open or shorted MUX circuit as required.
(3) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #12 for battery voltage, while observing the
voltmeter depress the left heated seat switchlow
setting twice, voltage should toggle between
approx.12v and 8v, If OK go to Step 4. If NOT OK
check for continuity between the switch and control
module on the low heat driver circuit, If OK replace
the heated seat control module.
(4) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #14 for battery voltage, while observing the
voltmeter depress the left heated seat switchhigh
setting twice, voltage should toggle between
approx.12v and 8v, If OK go to Step 5. If NOT OK
check for continuity between the switch and control
module on the high heat driver circuit, If OK replace
the heated seat control module.
8E - 22 ELECTRONIC CONTROL MODULESBR/BE
HEATED SEAT MODULE (Continued)
Page 388 of 2255
(5) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #2 for approx. 5v, 5 voltage should be present,
If OK go to Step 6. If NOT OK replace the heated
seat control module.
(6) Back-probe the heated seat module wire har-
ness connector, do not disconnect. Check cavity #8 for
a range in voltage from 1.72v (warm seat) ± 3.0v
(cold seat). It should be within this range, If OK
replace the heated seat control module. If NOT OK,
test the Heated Seat Sensor. If NOT OK, replace the
left heated seat element and sensor assembly. If the
heated seat sensor tests OK, check for continuity
between the left heated seat cushion connector and
control module connector on the 5v supply circuit, If
NOT OK, repair the open or shorted 5v supply circuit
as required. If OK check for continuity between the
left heated seat cushion connector and control mod-
ule connector on the temperature sensor input cir-
cuit. If NOT OK, repair the open or shorted
temperature sensor input circuit as required. If OK
replace the heated seat control module.
BOTH SEATS INOPERATIVE
If both seats (driver and passenger) fail to heat
and the indicator lamps on the heated seat switches
for both seats fail to operate, test the heated seat
relay and/or fuses. Refer toRelay Diagnosis and
Testingin the Power Distribution section for heated
seat relay diagnosis and testing procedures. If the
heated seat relay checks OK, go to Step 1.
(1) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check for
continuity between the ground circuit cavity #13 of
the heated seat module connector and a good ground.
If OK go to Step 2. If NOT OK, repair the open or
shorted ground circuit as required.
(2) Back-probe the heated seat module wire har-
ness connector (Fig. 20) , do not disconnect. Check
cavity #4 and #6 for battery voltage, voltage should
be present, If OK go to Step 3. If NOT OK repair the
open or shorted fused B(+) circuit as required.
(3) Back-probe the heated seat module wire har-
ness connector, do not disconnect. Check cavity #2 for
approx. 5v, voltage should be present, replace the
heated seat control module with a known good mod-
ule and verify system operation.
REMOVAL
(1) Working under the center front seat console,
cut the tiestrap and remove the two push-on retain-
ers that secure the mounting tabs of the heated seat
module to the of the mounting bracket.
(2) Position the driver seat to the full forward and
inclined position and working under the center of the
front seat, from behind the seat, disconnect the seat
wire harness connector from the connector receptacle
on the back of the heated seat module (Fig. 21).
(3) Remove the heated seat module from under the
front seat.
INSTALLATION
(1) Working under the front seat connect the seat
wire harness connector to the connector receptacle on
the back of the heated seat module.
(2) Position the driver seat in the full rearward
and reclined position, and working under the front of
the seat, install the two push-on retainers onto the
heated seat module mounting tabs to secure the mod-
ule to the top of the mounting bracket or install
tiestrap.
Fig. 21 Heated Seat Module Remove/Install
1 - MOUNTING BRACKET
2 - HEATED SEAT MODULE
3 - MOUNTING TABS
4 - PUSH-ON RETAINERS
BR/BEELECTRONIC CONTROL MODULES 8E - 23
HEATED SEAT MODULE (Continued)
Page 409 of 2255
VOLTAGE DROP TEST
WARNING: MODELS EQUIPPED WITH THE DIESEL
ENGINE OPTION ALSO HAVE AN AUTOMATIC
SHUTDOWN (ASD) RELAY LOCATED IN THE
POWER DISTRIBUTION CENTER (PDC), IN THE
ENGINE COMPARTMENT. HOWEVER, REMOVAL OF
THE ASD RELAY MAY NOT PREVENT THE DIESEL
ENGINE FROM STARTING. BE CERTAIN TO ALSO
DISCONNECT THE FUEL SHUTDOWN SOLENOID
WIRE HARNESS CONNECTOR ON MODELS WITH A
DIESEL ENGINE. FAILURE TO DO SO MAY RESULT
IN PERSONAL INJURY.
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing this
test, be certain that the following procedures are
accomplished:
²The battery is fully-charged and load tested
(Refer to 8 - ELECTRICAL/BATTERY SYSTEM/BAT-
TERY - STANDARD PROCEDURE).
²Fully engage the parking brake.
²If the vehicle is equipped with an automatic
transmission, place the gearshift selector lever in the
Park position. If the vehicle is equipped with a man-
ual transmission, place the gearshift selector lever in
the Neutral position and block the clutch pedal in the
fully depressed position.
²Verify that all lamps and accessories are turned
off.
²To prevent a gasoline engine from starting,
remove the Automatic ShutDown (ASD) relay. The
ASD relay is located in the Power Distribution Cen-
ter (PDC), in the engine compartment. See the fuse
and relay layout label affixed to the underside of the
PDC cover for ASD relay identification and location.
To prevent a diesel engine from starting, disconnect
the fuel shutdown solenoid wire harness connector
(Fig. 20).
(1) Connect the positive lead of the voltmeter to
the battery negative terminal post. Connect the neg-
ative lead of the voltmeter to the battery negative
cable terminal clamp (Fig. 21). Rotate and hold the
ignition switch in the Start position. Observe the
voltmeter. If voltage is detected, correct the poor con-
nection between the battery negative cable terminal
clamp and the battery negative terminal post.
NOTE: If the vehicle is equipped with a dual battery
system, Step 1 must be performed twice, once for
each battery.
(2) Connect the positive lead of the voltmeter to
the battery positive terminal post. Connect the nega-
tive lead of the voltmeter to the battery positive cable
terminal clamp (Fig. 22). Rotate and hold the ignition
switch in the Start position. Observe the voltmeter. Ifvoltage is detected, correct the poor connection
between the battery positive cable terminal clamp
and the battery positive terminal post.
Fig. 20 Fuel Shutdown Solenoid Connector - Diesel
Engine
1 - AIR TEMPERATURE SENSOR
2 - SENSOR ELECTRICAL CONNECTOR
3 - SOLENOID ELECTRICAL CONNECTOR
4 - FUEL SHUTDOWN SOLENOID
5 - INTAKE MANIFOLD (UPPER HALF)
Fig. 21 Test Battery Negative Connection
Resistance - Typical
1 - VOLTMETER
2 - BATTERY
8F - 20 BATTERY SYSTEMBR/BE
BATTERY CABLE (Continued)
Page 412 of 2255
BATTERY TRAY
DESCRIPTION
The battery is mounted in a molded plastic tray
(Fig. 25) with an integral support located in the left
front corner of the engine compartment. A U-nut held
in a molded formation on each side of the battery
tray provides anchor points for the battery hold down
bolts. The battery tray is secured on the outboard
side to the inner fender shield by two hex screws
with washers, and from underneath the integral bat-
tery tray support is secured to the left front wheel-
house inner panel by two stud plates. Each stud
plate has two studs and is secured by two nuts with
washers. The stud plate that secures the front of the
battery tray support to the wheelhouse inner panel is
installed through the wheelhouse panel from the top.
The stud plate that secures the rear of the battery
tray support to the wheelhouse inner panel is
installed through the wheelhouse panel from the bot-
tom.
A hole in the bottom of the battery tray is fitted
with a battery temperature sensor (Refer to 8 -
ELECTRICAL/CHARGING/BATTERY TEMPERA-
TURE SENSOR - DESCRIPTION). Models that are
equipped with an optional vehicle speed control sys-tem have the speed control servo secured to the inte-
gral battery tray support.
Models that are equipped with the diesel engine
option have a second battery tray located in the right
front corner of the engine compartment. This second
battery tray and its mounting are mirror image of
the standard equipment left battery tray. However,
the right battery tray and support have no provisions
for a battery temperature sensor or a speed control
servo mounting bracket.
OPERATION
The battery tray provides a secure mounting loca-
tion and supports the battery. On some vehicles, the
battery tray also provides the anchor point/s for the
battery holddown hardware. The battery tray and
the battery holddown hardware combine to secure
and stabilize the battery in the engine compartment,
which prevents battery movement during vehicle
operation. Unrestrained battery movement during
vehicle operation could result in damage to the vehi-
cle, the battery, or both.
REMOVAL
(1) Remove the battery from the battery tray
(Refer to 8 - ELECTRICAL/BATTERY SYSTEM/BAT-
TERY - REMOVAL).
(2) If the left battery tray is being removed,
remove the battery temperature sensor from the left
battery tray (Refer to 8 - ELECTRICAL/CHARGING/
BATTERY TEMPERATURE SENSOR - REMOVAL).
(3) Remove the two screws with washers that
secure the outboard side of the battery tray to the
inner fender shield (Fig. 26).
(4) From the engine compartment, remove the two
nuts with washers that secure the rear of the battery
tray support to the two studs that extend through
the top of the front wheelhouse inner panel.
(5) From inside the front fender wheelhouse,
remove the two nuts with washers that secure the
front of the battery tray support to the two studs
that extend through the underside of the front wheel-
house inner panel.
(6) From inside the front fender wheelhouse,
remove the stud plate that secures the rear of the
battery tray support from the underside of the front
wheelhouse inner panel.
(7) From the engine compartment, remove the bat-
tery tray and the stud plate that secures the front of
the battery tray support from the front wheelhouse
inner panel as a unit.
(8) If the vehicle is equipped with the optional
vehicle speed control package, the speed control servo
must be removed from the left battery tray support
to complete battery tray removal.
Fig. 25 Battery Tray - Typical
1 - STUD PLATE (2)
2 - NUT AND WASHER (4)
3 - FRONT WHEELHOUSE INNER PANEL
4 - SPEED CONTROL SERVO
5 - TRAY
6 - SCREW AND WASHER (2)
7 - BATTERY TREMPERATURE SENSOR
8 - U-NUT (2)
9 - FENDER INNER SHIELD
BR/BEBATTERY SYSTEM 8F - 23
Page 413 of 2255
INSTALLATION
(1) Clean and inspect the battery tray (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM - CLEANING).
(2) If the vehicle is equipped with the optional
vehicle speed control package, the speed control servo
must be installed onto the left battery tray support
to complete battery tray installation.(3) Install the stud plate onto the front of the bat-
tery tray support.
(4) From the engine compartment, position the
battery tray and the stud plate that secures the front
of the battery tray support onto the front wheelhouse
inner panel as a unit.
(5) From inside the front fender wheelhouse,
loosely install the two nuts with washers that secure
the front of the battery tray support to the two studs
that extend through the underside of the front wheel-
house inner panel.
(6) From inside the front fender wheelhouse, posi-
tion the stud plate that secures the rear of the bat-
tery tray support onto the underside of the front
wheelhouse inner panel.
(7) From the engine compartment, loosely install
the two nuts with washers that secure the rear of the
battery tray support to the two studs that extend
through the top of the front wheelhouse inner panel.
(8) Install and tighten the two screws with wash-
ers that secure the outboard side of the battery tray
to the inner fender shield. Tighten the screws to 15.8
N´m (140 in. lbs.).
(9) Final tighten the four nuts with washers that
secure the battery tray support to the stud plates on
the front wheelhouse inner panel. Tighten the nuts
to 15.8 N´m (140 in. lbs.).
(10) If the left battery tray is being installed,
install the battery temperature sensor onto the left
battery tray (Refer to 8 - ELECTRICAL/CHARGING/
BATTERY TEMPERATURE SENSOR - INSTALLA-
TION).
(11) Install the battery onto the battery tray (Refer
to 8 - ELECTRICAL/BATTERY SYSTEM/BATTERY -
INSTALLATION).
Fig. 26 Left Battery Tray Remove/Install - Typical for
Right Battery Tray
1 - STUD PLATE (2)
2 - NUT AND WASHER (4)
3 - FRONT WHEELHOUSE INNER PANEL
4 - SPEED CONTROL SERVO
5 - TRAY
6 - SCREW AND WASHER (2)
7 - BATTERY TREMPERATURE SENSOR
8 - U-NUT (2)
9 - FENDER INNER SHIELD
8F - 24 BATTERY SYSTEMBR/BE
BATTERY TRAY (Continued)
Page 414 of 2255
CHARGING
TABLE OF CONTENTS
page page
CHARGING
DESCRIPTION.........................25
OPERATION...........................25
DIAGNOSIS AND TESTING - CHARGING
SYSTEM............................25
SPECIFICATIONS
GENERATOR RATINGS.................26
SPECIFICATIONS - TORQUE -
GENERATOR/CHARGING SYSTEM........27
BATTERY TEMPERATURE SENSOR
DESCRIPTION.........................27OPERATION...........................27
REMOVAL.............................27
INSTALLATION.........................28
GENERATOR
DESCRIPTION.........................28
OPERATION...........................28
REMOVAL.............................28
INSTALLATION.........................30
VOLTAGE REGULATOR
DESCRIPTION.........................30
OPERATION...........................30
CHARGING
DESCRIPTION
The charging system consists of:
²Generator
²Electronic Voltage Regulator (EVR) circuitry
within the Powertrain Control Module (PCM)
²Ignition switch
²Battery (refer to 8, Battery for information)
²Battery temperature sensor
²Check Gauges Lamp (if equipped)
²Voltmeter (refer to 8, Instrument Panel and
Gauges for information)
²Wiring harness and connections (refer to 8, Wir-
ing Diagrams for information)
OPERATION
The charging system is turned on and off with the
ignition switch. The system is on when the engine is
running and the ASD relay is energized. When the
ASD relay is on, voltage is supplied to the ASD relay
sense circuit at the PCM. This voltage is connected
through the PCM and supplied to one of the genera-
tor field terminals (Gen. Source +) at the back of the
generator.
The amount of direct current produced by the gen-
erator is controlled by the EVR (field control) cir-
cuitry contained within the PCM. This circuitry is
connected in series with the second rotor field termi-
nal and ground.
A battery temperature sensor, located in the bat-
tery tray housing, is used to sense battery tempera-
ture. This temperature data, along with data from
monitored line voltage, is used by the PCM to vary
the battery charging rate. This is done by cycling theground path to control the strength of the rotor mag-
netic field. The PCM then compensates and regulates
generator current output accordingly.
All vehicles are equipped with On-Board Diagnos-
tics (OBD). All OBD-sensed systems, including EVR
(field control) circuitry, are monitored by the PCM.
Each monitored circuit is assigned a Diagnostic Trou-
ble Code (DTC). The PCM will store a DTC in elec-
tronic memory for certain failures it detects. Refer to
On-Board Diagnostics in 25, Emission Control Sys-
tem for more DTC information and a list of codes.
The Check Gauges Lamp (if equipped) monitors:
charging system voltage,engine coolant tempera-
ture and engine oil pressure. If an extreme condition
is indicated, the lamp will be illuminated. This is
done as reminder to check the three gauges. The sig-
nal to activate the lamp is sent via the CCD bus cir-
cuits. The lamp is located on the instrument panel.
Refer to 8, Instrument Panel and Gauges for addi-
tional information.
DIAGNOSIS AND TESTING - CHARGING
SYSTEM
The following procedures may be used to diagnose
the charging system if:
²the check gauges lamp (if equipped) is illumi-
nated with the engine running
²the voltmeter (if equipped) does not register
properly
²an undercharged or overcharged battery condi-
tion occurs.
Remember that an undercharged battery is often
caused by:
²accessories being left on with the engine not
running
BR/BECHARGING 8F - 25
Page 416 of 2255
SPECIFICATIONS - TORQUE - GENERATOR/
CHARGING SYSTEM
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Generator Mounting Bolts
- Gas Engine41 30-
Generator Upper Mounting
Bolt - Diesel Engine54 40 -
Generator Pivot Bolt/Nut -
Diesel Engine54 40 -
Generator Mounting
Bracket-to-Engine Bolt -
Diesel Engine24 18 -
Generator B+ Cable
Eyelet Nut12 9 108
BATTERY TEMPERATURE
SENSOR
DESCRIPTION
The Battery Temperature Sensor (BTS) is attached
to the battery tray located under the battery.
OPERATION
The BTS is used to determine the battery temper-
ature and control battery charging rate. This temper-
ature data, along with data from monitored line
voltage, is used by the PCM to vary the battery
charging rate. System voltage will be higher at colder
temperatures and is gradually reduced at warmer
temperatures.
The PCM sends 5 volts to the sensor and is
grounded through the sensor return line. As temper-
ature increases, resistance in the sensor decreases
and the detection voltage at the PCM increases.
The BTS is also used for OBD II diagnostics. Cer-
tain faults and OBD II monitors are either enabled
or disabled, depending upon BTS input (for example,
disable purge and enable Leak Detection Pump
(LDP) and O2 sensor heater tests). Most OBD II
monitors are disabled below 20ÉF.
REMOVAL
The battery temperature sensor is located under
the vehicle battery (Fig. 1) and is attached (snapped
into) a mounting hole on battery tray. On models
equipped with a diesel engine (dual batteries), only
one sensor is used. The sensor is located under the
battery on drivers side of vehicle.
(1) Remove battery. Refer to 8, Battery for proce-
dures.Fig. 1 Battery Temperature Sensor Location
1 - BATT. TEMP. SENSOR
2 - BATTERY HOLD DOWN STRAP
3 - PIGTAIL HARNESS
4 - U-NUT
5 - U-NUT
6 - ELEC. CONNEC.
BR/BECHARGING 8F - 27
CHARGING (Continued)
Page 417 of 2255
(2) Disconnect sensor pigtail harness from engine
wire harness.
(3) Pry sensor straight up from battery tray
mounting hole.
INSTALLATION
The battery temperature sensor is located under
the vehicle battery (Fig. 1) and is attached (snapped
into) a mounting hole on battery tray. On models
equipped with a diesel engine (dual batteries), only
one sensor is used. The sensor is located under the
battery on drivers side of vehicle.
(1) Feed pigtail harness through mounting hole in
top of battery tray and press sensor into top of tray
(snaps in).
(2) Connect pigtail harness.
(3) Install battery. Refer to 8A, Battery for proce-
dures.
GENERATOR
DESCRIPTION
The generator is belt-driven by the engine using a
serpentine type drive belt. It is serviced only as a
complete assembly. If the generator fails for any rea-
son, the entire assembly must be replaced.
OPERATION
As the energized rotor begins to rotate within the
generator, the spinning magnetic field induces a cur-
rent into the windings of the stator coil. Once the
generator begins producing sufficient current, it also
provides the current needed to energize the rotor.
The Y type stator winding connections deliver the
induced alternating current to 3 positive and 3 neg-
ative diodes for rectification. From the diodes, recti-
fied direct current is delivered to the vehicle
electrical system through the generator battery ter-
minal.
Although the generators appear the same exter-
nally, different generators with different output rat-
ings are used on this vehicle. Be certain that the
replacement generator has the same output rating
and part number as the original unit. Refer to Gen-
erator Ratings in the Specifications section at the
back of this group for amperage ratings and part
numbers.
Noise emitting from the generator may be caused
by: worn, loose or defective bearings; a loose or defec-
tive drive pulley; incorrect, worn, damaged or misad-
justed fan drive belt; loose mounting bolts; a
misaligned drive pulley or a defective stator or diode.
REMOVAL
WARNING: DISCONNECT NEGATIVE CABLE FROM
BATTERY BEFORE REMOVING BATTERY OUTPUT
WIRE (B+ WIRE) FROM GENERATOR. FAILURE TO
DO SO CAN RESULT IN INJURY OR DAMAGE TO
ELECTRICAL SYSTEM.
(1) Disconnect negative battery cable at battery.
Diesel Engines: Disconnect both negative battery
cables at both batteries.
(2) Remove generator drive belt. Refer to 7, Cool-
ing System for procedure.
(3) Gasoline Engines: Remove generator pivot and
mounting bolts/nut (Fig. 2) or (Fig. 3).
(4) Diesel Engines: Loosen (but do not remove)
generator mounting bracket-to-engine bolt (Fig. 4).
(5) All Engines: Remove upper generator mounting
bolt and lower mounting bolt/nut.
(6) Remove B+ terminal mounting nut at rear of
generator (Fig. 5) or (Fig. 6). Disconnect terminal
from generator.
(7) Disconnect field wire connector at rear of gen-
erator by pushing on connector tab.
(8) Remove generator from vehicle.
Fig. 2 Remove/Install GeneratorÐ5.9L Engines
1 - MOUNTING BOLT
2 - GENERATOR
3 - MOUNTING BRACKET
4 - MOUNTING BOLT/NUT
8F - 28 CHARGINGBR/BE
BATTERY TEMPERATURE SENSOR (Continued)
Page 419 of 2255
INSTALLATION
(1) Position generator to engine and snap field
wire connector into rear of generator.
(2) Install B+ terminal eyelet to generator stud.
Tighten mounting nut to 12 N´m (108 in. lbs.) torque.
(3) Install generator mounting fasteners and
tighten as follows:
²Generator mounting boltÐAll gas powered
enginesÐ41 N´m (30 ft. lbs.) torque.
²Generator pivot bolt/nutÐAll gas powered
enginesÐ41 N´m (30 ft. lbs.) torque.
²Generator mounting boltÐDiesel powered
enginesÐ54 N´m (40 ft. lbs.) torque.
²Generator pivot bolt/nutÐDiesel powered
enginesÐ54 N´m (40 ft. lbs.) torque.
CAUTION: Never force a belt over a pulley rim
using a screwdriver. The synthetic fiber of the belt
can be damaged.
CAUTION: When installing a serpentine accessory
drive belt, the belt MUST be routed correctly. The
water pump will be rotating in the wrong direction if
the belt is installed incorrectly, causing the engine
to overheat. Refer to belt routing label in engine
compartment, or refer to Belt Schematics in Group
7, Cooling System.
(4) Install generator drive belt. Refer to 7, Cooling
System for procedure.
(5) Install negative battery cable(s) to battery(s).
VOLTAGE REGULATOR
DESCRIPTION
The Electronic Voltage Regulator (EVR) is not a
separate component. It is actually a voltage regulat-
ing circuit located within the Powertrain Control
Module (PCM). The EVR is not serviced separately. If
replacement is necessary, the PCM must be replaced.
OPERATION
The amount of direct current produced by the gen-
erator is controlled by EVR circuitry contained
within the PCM. This circuitry is connected in series
with the generators second rotor field terminal and
its ground.
Voltage is regulated by cycling the ground path to
control the strength of the rotor magnetic field. The
EVR circuitry monitors system line voltage (B+) and
battery temperature (refer to Battery Temperature
Sensor for more information). It then determines a
target charging voltage. If sensed battery voltage is
0.5 volts or lower than the target voltage, the PCM
grounds the field winding until sensed battery volt-
age is 0.5 volts above target voltage. A circuit in the
PCM cycles the ground side of the generator field up
to 100 times per second (100Hz), but has the capabil-
ity to ground the field control wire 100% of the time
(full field) to achieve the target voltage. If the charg-
ing rate cannot be monitored (limp-in), a duty cycle
of 25% is used by the PCM in order to have some
generator output. Also refer to Charging System
Operation for additional information.
8F - 30 CHARGINGBR/BE
GENERATOR (Continued)
Page 436 of 2255
HEATED SEAT SYSTEM
TABLE OF CONTENTS
page page
HEATED SEAT SYSTEM
DESCRIPTION..........................5
OPERATION............................6
DIAGNOSIS AND TESTING - HEATED SEAT
SYSTEM.............................6
DRIVER SEAT HEATER SWITCH
DESCRIPTION..........................7
OPERATION............................8
DIAGNOSIS AND TESTING - HEATED SEAT
SWITCH.............................8
REMOVAL.............................9
INSTALLATION.........................10
HEATED SEAT ELEMENT
DESCRIPTION.........................10
OPERATION...........................11
DIAGNOSIS AND TESTING - HEATED SEAT
ELEMENT AND SENSOR................11REMOVAL.............................13
INSTALLATION.........................13
HEATED SEAT RELAY
DESCRIPTION.........................14
OPERATION...........................15
DIAGNOSIS AND TESTING - HEATED SEAT
RELAY..............................15
REMOVAL.............................16
INSTALLATION.........................16
PASSENGER SEAT HEATER SWITCH
DESCRIPTION.........................16
OPERATION...........................17
DIAGNOSIS AND TESTING - HEATED SEAT
SWITCH............................17
REMOVAL.............................18
INSTALLATION.........................19
HEATED SEAT SYSTEM
DESCRIPTION
Individually controlled electrically heated front
seats are available factory-installed optional equip-
ment on the Ram quad cab models that are also
equipped with the optional SLT Plus (leather) trim
package. Vehicles with this option can be visually
identified by the two separate heated seat switches
mounted in a bezel located in the lower right corner
of the instrument cluster bezel, next to the radio
receiver (Fig. 1). The heated seat system allows the
front seat driver and passenger to select from two
different levels of supplemental electrical seat heat-
ing, or no seat heating to suit their individual com-
fort requirements. The heated seat system for this
vehicle includes the following major components,
which are described in further detail later in this sec-
tion:
²Heated Seat Switches- Two heated seat
switches are used per vehicle, including two Light-
Emitting Diode (LED) indicator lamps and an incan-
descent back lighting bulb for each switch. One
switch for the driver and one for the passenger front
seats. The switches are mounted in the instrument
panel, next to the radio.
²Heated Seat Module- also referred to as the
Seat Heat Interface Module (SHIM), this module con-
tains the solid state electronic control and diagnostic
logic circuitry for the heated seat system. One heated
seat module is used per vehicle and is mounted
under the center front seat cushion. Refer to the
Electronic Control Modules section of the service
manual for heated seat module information.
Fig. 1 Heated Seat System Switches
1 - Radio Receiver
2 - Heated Seat Switches
BR/BEHEATED SEAT SYSTEM 8G - 5