2002 DODGE RAM climate control

²Airbag Control Module- The Airbag Control
Module (ACM) is located in a stamped mounting
bracket on the floor panel transmission tunnel, below
the center of the instrument panel.
²Airbag Indicator- The airbag indicator is inte-
gral to the ElectroMechanical Instrument Cluster
(EMIC), which is located on the instrument panel in
front of the driver.
²Clockspring- The clockspring is located near
the top of the steering column, directly beneath the
steering wheel.
²Driver Airbag- The driver airbag is located in
the center of the steering wheel, beneath the driver
airbag trim cover.
²Driver Knee Blocker- The driver knee blocker
is a molded plastic structural unit secured to the
back side of and integral to the instrument panel
steering column opening cover.
²Passenger Airbag- The passenger airbag is
located on the instrument panel, beneath the passen-
ger airbag door on the instrument panel above the
glove box on the passenger side of the vehicle.
²Passenger Airbag On/Off Switch- The pas-
senger airbag on/off switch is located in a dedicated
opening in the upper right corner of the instrument
panel cluster bezel, to the right of the center panel
outlets of the climate control system.
²Passenger Knee Blocker- The passenger knee
blocker is a structural reinforcement that is integral
to and concealed within the glove box door.
The ACM and the EMIC each contain a central
processing unit and programming that allow them to
communicate with each other using the Chrysler Col-
lision Detection (CCD) data bus network. This
method of communication is used for control of the
airbag indicator on all models. (Refer to 8 - ELEC-
TRICAL/ELECTRONIC CONTROL MODULES/
COMMUNICATION - DESCRIPTION).Hard wired circuitry connects the airbag system
components to each other through the electrical sys-
tem of the vehicle. These hard wired circuits are
integral to several wire harnesses, which are routed
throughout the vehicle and retained by many differ-
ent methods. These circuits may be connected to each
other, to the vehicle electrical system, and to the air-
bag system components through the use of a combi-
nation of soldered splices, splice block connectors,
and many different types of wire harness terminal
connectors and insulators. Refer to the appropriate
wiring information. The wiring information includes
wiring diagrams, proper wire and connector repair
procedures, further details on wire harness routing
and retention, as well as pin-out and location views
for the various wire harness connectors, splices and
grounds.OPERATION
The airbag system is referred to as a supplemental
restraint system because it was designed and is
intended to enhance the protection for the front seat
occupants of the vehicleonlywhen used in conjunc-
tion with the seat belts. It is referred to as a passive
system because the vehicle occupants are not
required to do anything to make it work. The pri-
mary passenger restraints in this or any other vehi-
cle are the standard equipment factory-installed seat
belts. Seat belts are referred to as an active restraint
because the vehicle occupants are required to physi-
cally fasten and properly adjust these restraints in
order to benefit from them. The vehicle occupants
must be wearing their seat belts in order to obtain
the maximum safety benefit from the factory-in-
stalled airbag system.
The airbag system electrical circuits are continu-
ously monitored and controlled by a microprocessor
and software contained within the Airbag Control
Module (ACM). An airbag indicator in the ElectroMe-
chanical Instrument Cluster (EMIC) lights for about
seven seconds as a bulb test each time the ignition
switch is turned to the On or Start positions. Follow-
ing the bulb test, the airbag indicator is turned on or
off by the ACM to indicate the status of the airbag
system. If the airbag indicator comes on at any time
other than during the bulb test, it indicates that
there is a problem in the airbag system electrical cir-
cuits. Such a problem may cause the airbags not to
deploy when required, or to deploy when not
required.
The clockspring on the top of the steering column
allows a continuous electrical circuit to be main-
tained between the stationary steering column and
the driver airbag inflator, which rotates with the
steering wheel. The passenger airbag on/off switch
allows the passenger side airbag to be disabled when
Fig. 1 SRS Logo
8O - 2 RESTRAINTSBR/BE
RESTRAINTS (Continued)

SYMBOLS
International symbols are used throughout the wir-
ing diagrams. These symbols are consistent with
those being used around the world (Fig. 3).
TERMINOLOGY
This is a list of terms and definitions used in the
wiring diagrams.
LHD .................Left Hand Drive Vehicles
RHD................Right Hand Drive Vehicles
ATX . . Automatic Transmissions-Front Wheel Drive
MTX....Manual Transmissions-Front Wheel Drive
AT ....Automatic Transmissions-Rear Wheel Drive
MT .....Manual Transmissions-Rear Wheel Drive
SOHC...........Single Over Head Cam Engine
DOHC..........Double Over Head Cam Engine
Built-Up-Export........ Vehicles Built For Sale In
Markets Other Than North America
Except-Built-Up-Export . . Vehicles Built For Sale In
North America
DESCRIPTION - CIRCUIT INFORMATION
Each wire shown in the diagrams contains a code
which identifies the main circuit, part of the main
circuit, gage of wire, and color (Fig. 4).
WIRE COLOR CODE CHART
COLOR CODE COLOR
BL BLUE
BK BLACK
BR BROWN
DB DARK BLUE
DG DARK GREEN
GY GRAY
LB LIGHT BLUE
LG LIGHT GREEN
OR ORANGE
PK PINK
RD RED
TN TAN
VT VIOLET
WT WHITE
YL YELLOW
* WITH TRACER
DESCRIPTION - CIRCUIT FUNCTIONS
All circuits in the diagrams use an alpha/numeric
code to identify the wire and it's function. To identify
which circuit code applies to a system, refer to the
Circuit Identification Code Chart. This chart shows
the main circuits only and does not show the second-
ary codes that may apply to some models.
CIRCUIT IDENTIFICATION CODE CHART
CIRCUIT FUNCTION
A BATTERY FEED
B BRAKE CONTROLS
C CLIMATE CONTROLS
D DIAGNOSTIC CIRCUITS
E DIMMING ILLUMINATION
CIRCUITS
F FUSED CIRCUITS
G MONITORING CIRCUITS
(GAUGES)
H OPEN
I NOT USED
J OPEN
K POWERTRAIN CONTROL
MODULE
L EXTERIOR LIGHTING
M INTERIOR LIGHTING
N NOT USED
O NOT USED
P POWER OPTION (BATTERY
FEED)
Q POWER OPTIONS (IGNITION
FEED)
R PASSIVE RESTRAINT
S SUSPENSION/STEERING
T TRANSMISSION/TRANSAXLE/
TRANSFER CASE
U OPEN
V SPEED CONTROL, WIPER/
WASHER
W OPEN
X AUDIO SYSTEMS
Y OPEN
Z GROUNDS
8W - 01 - 4 8W-01 WIRING DIAGRAM INFORMATIONBR/BE
WIRING DIAGRAM INFORMATION (Continued)

INSTRUMENT PANEL SYSTEM
TABLE OF CONTENTS
page page
INSTRUMENT PANEL SYSTEM
DESCRIPTION........................105
OPERATION..........................106
ASH RECEIVER
REMOVAL............................107
INSTALLATION........................107
CLUSTER BEZEL
REMOVAL............................108
INSTALLATION........................108
CUBBY BIN
REMOVAL............................108
INSTALLATION........................109
CUP HOLDER
REMOVAL............................109
INSTALLATION........................110
GLOVE BOX
REMOVAL
REMOVAL..........................110
DISASSEMBLY - GLOVE BOX...........110
ASSEMBLY - GLOVE BOX................111INSTALLATION........................111
GLOVE BOX LATCH STRIKER
REMOVAL............................111
INSTALLATION........................112
GLOVE BOX OPENING UPPER TRIM
REMOVAL............................112
INSTALLATION........................112
INSTRUMENT PANEL TOP COVER
REMOVAL............................113
INSTALLATION........................113
STEERING COLUMN OPENING COVER
REMOVAL............................113
INSTALLATION........................114
STORAGE BIN
REMOVAL............................114
INSTALLATION........................114
INSTRUMENT PANEL ASSEMBLY
REMOVAL............................115
INSTALLATION........................117
INSTRUMENT PANEL SYSTEM
DESCRIPTION
The instrument panel is located at the front of the
passenger compartment. This instrument panel is
molded from a blend of various plastics that are
mechanically attached to the vehicle. Colors are
molded into the plastic components to minimize
appearance degradation from scratches or abrasions.
The panel components are internally ribbed and riv-
eted to steel reinforcements for additional structural
integrity and dimensional stability. The instrument
panel surface components are designed to deform
upon impact without breaking. This type of construc-
tion provides improved energy absorption which, in
conjunction with the dual airbags and seat belts,
helps to improve occupant protection.
The top of the instrument panel is secured to the
top of the dash panel near the base of the windshield
using screws. An end bracket integral to each end of
the instrument panel structure is secured to each
cowl side inner panel with a screw. A stamped metal
bracket supports the center of the instrument panel
by securing it to the top of the floor panel transmis-
sion tunnel below the instrument panel with screws.
The instrument cluster, radio, heater-air conditioner
control, passenger airbag, glove box, electrical junc-tion block, Central Timer Module (CTM), accessory
switches, ash receiver, cigar lighter, accessory power
outlet, park brake release handle, inside hood release
handle, as well as numerous other components are
secured to and supported by this unit.
The instrument panel for this vehicle includes the
following major features:
²Cluster Bezel- This molded plastic bezel is
secured with snap clips to the instrument panel sup-
porting structure. It trims out the edges of the head-
lamp switch, instrument cluster, radio, heater-air
conditioner controls, passenger airbag on-off switch,
and the heated seat switches on vehicles so equipped.
On vehicles without the heated seat option, a small
storage cubby bin is provided in the cluster bezel.
This bezel also incorporates three completely adjust-
able panel outlets for the climate control system, and
fills the opening between the instrument cluster and
the top of the steering column where it passes
through the instrument panel.
²Cup Holder/Storage Bin- Vehicles equipped
with an automatic transmission feature a latching
fold-down, adjustable cup holder located on the lower
instrument panel between the glove box and the ash
receiver. Vehicles equipped with a manual transmis-
sion have a lighted storage bin on the instrument
panel in place of the cup holder.
BR/BEINSTRUMENT PANEL SYSTEM 23 - 105

²Glove Box- The hinged bin-type glove box in
the passenger side of the instrument panel features a
recessed paddle-operated latch handle. Three molded
hook formations on the lower edge of the glove box
door are engaged with and pivot on three hinge pins
integral to the lower edge of the instrument panel
support structure. The glove box door also serves as
the passenger side knee blocker. A honeycomb struc-
ture between the inner and outer glove box door pan-
els helps to absorb the impact load and distribute it
to the instrument panel structure.
²Steering Column Opening Cover- The steer-
ing column opening cover serves as the driver side
knee blocker. This molded plastic cover has an inte-
gral ribbed plastic liner concealed behind it, for
increased strength and integrity. The steering column
opening cover transfers impact loads to the instru-
ment panel structural support.
²Top Cover- The instrument panel top cover or
base trim is the molded, grained, and color impreg-
nated plastic outer skin of the instrument panel
structural support.
Hard wired circuitry connects the electrical compo-
nents on the instrument panel to each other through
the electrical system of the vehicle. These hard wired
circuits are integral to several wire harnesses, which
are routed throughout the vehicle and retained by
many different methods. These circuits may be con-
nected to each other, to the vehicle electrical system
and to the instrument panel components through the
use of a combination of soldered splices, splice block
connectors and many different types of wire harness
terminal connectors and insulators. Refer to the
appropriate wiring information. The wiring informa-
tion includes complete circuit diagrams, proper wire
and connector repair procedures, further details on
wire harness routing and retention, as well as pin-
out and location views for the various wire harness
connectors, splices, and grounds.
OPERATION
The instrument panel serves as the command cen-
ter of the vehicle, which necessarily makes it a very
complex unit. The instrument panel is designed to
house the controls and monitors for standard and
optional powertrains, climate control systems, audio
systems, safety systems, and many other comfort or
convenience items. When the components of the
instrument panel structural support are properly
assembled and secured in the vehicle they provide
superior instrument panel stiffness and integrity to
help reduce buzzes, squeaks, and rattles. This type of
construction also provides improved energy absorp-
tion which, in conjunction with the dual airbags and
seat belts, helps to improve occupant protection.The instrument panel is also designed so that all of
the various controls can be safely reached and the
monitors can be easily viewed by the vehicle operator
when driving, while still allowing relative ease of
access to each of these items for service. Modular
instrument panel construction allows all of the
gauges and controls to be serviced from the front of
the panel. In addition, most of the instrument panel
electrical components can be accessed without com-
plete instrument panel removal. However, if neces-
sary, the instrument panel can be removed from the
vehicle as an assembly.
The steering column opening cover with its inte-
gral knee blocker located on the driver side of the
instrument panel works in conjunction with the air-
bag system in a frontal vehicle impact to keep the
driver properly positioned for an airbag deployment.
In addition, removal of this component provides
access to the steering column mounts, the steering
column wiring, the Junction Block (JB) (removal of a
snap-fit fuse access panel on the left end of the
instrument panel allows access to the fuses and cir-
cuit breakers), the Central Timer Module (CTM), the
Infinity speaker filter choke and relay unit, much of
the instrument panel wiring, and the gear selector
indicator cable (automatic transmission).
In a frontal collision, the glove box door on the pas-
senger side of the instrument panel provides the
same function for the front seat passenger as the
knee blocker does for the driver. The glove box door
also incorporates a recessed latch handle. Removal of
the glove box provides access to the passenger airbag,
the glove box lamp and switch, the radio antenna
coaxial cable, the heating and air conditioning vac-
uum harness connector, and additional instrument
panel wiring.
Removal of the instrument panel cluster bezel
allows access to the headlamp switch, instrument
cluster, radio, passenger airbag on-off switch, heated
seat switches (if equipped), and the heating and air
conditioning control. Removal of the instrument clus-
ter allows access to the cluster illumination and indi-
cator bulbs, and more of the instrument panel
wiring. Complete instrument panel removal is
required for service of most components internal to
the heating and air conditioning system housing,
including the heater core and the evaporator.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of all of the components and systems mounted on or
in the instrument panel.
23 - 106 INSTRUMENT PANEL SYSTEMBR/BE
INSTRUMENT PANEL SYSTEM (Continued)

(1) The relay common feed terminal cavity (30) is
connected to fused battery feed. There should be bat-
tery voltage at the cavity for relay terminal 30 at all
times. If OK, go to Step 2. If not OK, repair the open
circuit to the fuse in the PDC as required.
(2) The relay normally closed terminal (87A) is not
used in this application. Go to Step 3.
(3) The relay normally open terminal cavity (87) is
connected to the compressor clutch coil. There should
be continuity between this cavity and the A/C com-
pressor clutch relay output circuit cavity of the com-
pressor clutch coil wire harness connector. If OK, go
to Step 4. If not OK, repair the open circuit as
required.
(4) The relay coil battery terminal (86) is con-
nected to the fused ignition switch output (run/start)
circuit. There should be battery voltage at the cavity
for relay terminal 86 with the ignition switch in the
On position. If OK, go to Step 5. If not OK, repair the
open circuit to the fuse in the junction block as
required.
(5) The coil ground terminal cavity (85) is switched
to ground through the Powertrain Control Module
(PCM). There should be continuity between this cav-
ity and the A/C compressor clutch relay control cir-
cuit cavity of the PCM wire harness connector C
(gray) at all times. If not OK, repair the open circuit
as required.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Power Distribution
Center (PDC) (Fig. 17).
(3) Refer to the label on the PDC for compressor
clutch relay identification and location.(4) Unplug the compressor clutch relay from the
PDC and remove it.
INSTALLATION
(1) Install the compressor clutch relay by aligning
the relay terminals with the cavities in the PDC and
pushing the relay firmly into place.
(2) Install the PDC cover.
(3) Connect the battery negative cable.
(4) Test the relay operation.
A/C-HEATER CONTROL
DESCRIPTION
Both the heater-only and a/c heater systems use a
combination of electrical and vacuum controls. These
controls provide the vehicle operator with a number
of setting options to help control the climate and
comfort within the vehicle. Refer to the owner's man-
ual in the vehicle glove box for more information on
the features, use, and suggested operation of these
controls.
OPERATION
The heater-only or a/c heater control panel is
located to the right of the instrument cluster on the
instrument panel. The control panel contains a rota-
ry-type temperature control knob, a rotary-type mode
control switch knob, and a rotary-type blower motor
speed switch knob. On models with the optional
heated mirror system, a momentary push button
switch and indicator lamp are located near the bot-
tom of the a/c heater control panel. Refer to Heated
Mirrors for more information on this feature.
The heater-only or a/c heater control panel cannot
be repaired. If faulty or damaged, the entire unit
must be replaced. The control knobs and the illumi-
nation lamps are available for service replacement.
DIAGNOSIS AND TESTING - A/C HEATER
CONTROL
Satisfactory heater and air conditioner perfor-
mance depends upon proper operation and adjust-
ment of all operating controls and refrigeration
system components. For circuit descriptions and dia-
grams, (Refer to Appropriate Wiring Information).
These inspections, tests, and adjustments should be
used to locate the cause of a malfunction.
Operation must be tested as described in the fol-
lowing sequence:
(1) Inspect and adjust the serpentine drive bel-
t(Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE
BELTS - DIAGNOSIS AND TESTING).
(2) Start the engine and hold the idle speed at
1,300 rpm.
Fig. 17 POWER DISTRIBUTION CENTER
1 - COVER
2 - POWER DISTRIBUTION CENTER
24 - 18 CONTROLSBR/BE
A/C COMPRESSOR CLUTCH RELAY (Continued)

(M)Malfunction Indicator Lamp (MIL) illuminated during engine operation if this DTC was recorded
(depending if required by CARB and/or EPA). MIL is displayed as an engine icon on instrument panel.
(G)Generator lamp illuminated
Generic Scan
Tool P-CodeDRB Scan Tool Display Brief Description of DTC
P1686 No SKIM BUS Messages Received No CCD/J1850 messages received from the Smart Key
Immobilizer Module (SKIM).
P1687 No MIC BUS Message (No Cluster
BUS Message)No CCD/J1850 messages received from the Mechanical
Instrument Cluster (MIC) module.
P1688 (M) Internal Fuel Injection Pump Controller
FailureInternal problem within the fuel injection pump. Low power,
engine derated, or engine stops.
P1689 (M) No Communication Between ECM and
Injection Pump ModuleData link circuit failure between ECM and fuel injection
pump. Low power, engine derated, or engine stops.
P1690 (M) Fuel Injection Pump CKP Sensor Does
Not Agree With ECM CKP SensorProblem in fuel sync signal. Possible injection pump timing
problem. Low power, engine derated, or engine stops.
P1691 Fuel Injection Pump Controller
Calibration ErrorInternal fuel injection pump failure. Low power, engine
derated, or engine stops.
P1692 DTC Set In ECM A9Companion DTC9was set in both the ECM and PCM.
P1693 (M) DTC Detected in Companion Module A fault has been generated in the companion engine control
module.
P1693 (M) DTC Detected in PCM/ECM or DTC
Detected in ECMA9Companion DTC9was set in both the ECM and PCM.
P1694 Fault In Companion Module No CCD/J1850 messages received from the powertrain
control module-Aisin transmission
P1694 (M) No BUS (CCD) Messages received
from ECMBus communication failure to PCM.
P1695 No CCD/J1850 Message From Body
Control ModuleNo CCD/J1850 messages received from the body control
module.
P1696 PCM Failure EEPROM Write Denied Unsuccessful attempt to write to an EEPROM location by the
control module.
P1697 PCM Failure SRI Mile Not Stored Unsuccessful attempt to update Service Reminder Indicator
(SRI or EMR) mileage in the control module EEPROM.
P1698 No CCD/J1850 Message From TCM No CCD/J1850 messages received from the electronic
transmission control module (EATX) or the Aisin transmission
controller.
P1698 No CCD Messages received from
PCMBus communication failure to PCM. A9Companion DTC9was
set in both the ECM and PCM.
P1699 No Climate Control Bus Messages
P1719 Skip Shift Solenoid Circuit An open or shorted condition detected in the transmission
2-3 gear lock-out solenoid control circuit.
P1740 TCC or OD Sol Perf A rationality error has been detected in either the TCC
solenoid or overdrive solenoid systems.
P1740 (M) TCC OR O/D Solenoid Performance Problem detected in transmission convertor clutch and/or
overdrive circuits (diesel engine with 4-speed auto. trans.
only).
P1756 (M) GOV Press Not Equal to Target @
15-20 PSIThe requested pressure and the actual pressure are not
within a tolerance band for the Governor Control System
which is used to regulate governor pressure to control shifts
for 1st, 2nd, and 3rd gear. (Mid Pressure Malfunction)
BR/BEEMISSIONS CONTROL 25 - 15
EMISSIONS CONTROL (Continued)