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Dodge Dakota (R1). Manual - part 323

DOOR AJAR INDICATOR

DESCRIPTION

A door ajar indicator is standard equipment on all

instrument

clusters.

However,

vehicles

not

equipped with this optional feature, this indicator is
electronically disabled. The door ajar indicator is
located in the Information Center area of the instru-
ment cluster, to the left of center. The door ajar indi-
cator consists of a stenciled cutout of the words
“DOOR AJAR” in the opaque layer of the instrument
cluster overlay. The dark outer layer of the overlay
prevents the indicator from being clearly visible
when it is not illuminated. A red lens behind the cut-
out in the opaque layer of the overlay causes the
“DOOR AJAR” text to appear in red through the
translucent outer layer of the overlay when the indi-
cator is illuminated from behind by a Light Emitting
Diode (LED) soldered onto the instrument cluster
electronic circuit board. The door ajar indicator is
serviced as a unit with the instrument cluster.

OPERATION

The door ajar indicator gives an indication to the

vehicle operator that one or more of the passenger
compartment doors may be open or not completely
latched. This indicator is controlled by a transistor
on the instrument cluster circuit board based upon
cluster

programming

and

electronic

messages

received by the cluster from the Central Timer Mod-
ule (CTM) over the Programmable Communications
Interface (PCI) data bus. The door ajar indicator
Light Emitting Diode (LED) receives battery current
on the instrument cluster electronic circuit board
through the fused ignition switch output (run-start)
circuit whenever the ignition switch is in the On or
Start positions; therefore, the LED will always be off
when the ignition switch is in any position except On
or Start. The LED only illuminates when it is pro-
vided a path to ground by the instrument cluster
transistor. The instrument cluster will turn on the
door ajar indicator for the following reasons:

• Bulb Test - Each time the ignition switch is

turned to the On position the door ajar indicator is
illuminated for about two seconds as a bulb test.

• Door Ajar Lamp-On Message - Each time the

cluster receives a door ajar lamp-on message from
the CTM indicating that a door is open or not com-
pletely latched, the door ajar indicator will be illumi-
nated. The indicator remains illuminated until the
cluster receives an door ajar lamp-off message from
the CTM, or until the ignition switch is turned to the
Off position, whichever occurs first.

• Actuator Test - Each time the cluster is put

through the actuator test, the door ajar indicator will
be turned on, then off again during the bulb check

portion of the test to confirm the functionality of the
cluster control circuitry.

The CTM continually monitors the door ajar

switches to determine the status of the doors. The
CTM then sends the proper door ajar lamp-on and
lamp-off messages to the instrument cluster. For fur-
ther diagnosis of the door ajar indicator or the
instrument cluster circuitry that controls the indica-
tor,

(Refer

ELECTRICAL/INSTRUMENT

CLUSTER

DIAGNOSIS AND

TESTING).

For

proper diagnosis of the door ajar switches and cir-
cuits, (Refer to 8 - ELECTRICAL/LAMPS/LIGHTING
- INTERIOR/DOOR AJAR SWITCH - DIAGNOSIS
AND TESTING). For proper diagnosis of the CTM,
the PCI data bus, or the message inputs to the
instrument cluster that control the door ajar indica-
tor, a DRBIII

t scan tool is required. Refer to the

appropriate diagnostic information.

ENGINE TEMPERATURE
GAUGE

DESCRIPTION

An engine coolant temperature gauge is standard

equipment on all instrument clusters. The engine
coolant temperature gauge is located in the lower left
quadrant of the instrument cluster, below the voltage
gauge. The engine coolant temperature gauge con-
sists of a movable gauge needle or pointer controlled
by the instrument cluster circuitry and a fixed 90
degree scale on the cluster overlay that reads left-to-
right from “C” (or Cold) to “H” (or Hot) for all
engines. An International Control and Display Sym-
bol icon for “Engine Coolant Temperature” is located
on the cluster overlay, in the center of the gauge
directly above the hub of the gauge needle. The
engine coolant temperature gauge graphics are white
against a black field except for a single red gradua-
tion at the high end of the gauge scale, making them
clearly visible within the instrument cluster in day-
light. When illuminated from behind by the panel
lamps dimmer controlled cluster illumination lighting
with the exterior lamps turned On, the white graph-
ics appear blue-green and the red graphics appear
red. The orange gauge needle is internally illumi-
nated. Gauge illumination is provided by replaceable
incandescent bulb and bulb holder units located on
the instrument cluster electronic circuit board. The
engine coolant temperature gauge is serviced as a
unit with the instrument cluster.

OPERATION

The engine coolant temperature gauge gives an

indication to the vehicle operator of the engine cool-
ant temperature. This gauge is controlled by the

8J - 18

INSTRUMENT CLUSTER

instrument cluster circuit board based upon cluster
programming and electronic messages received by
the cluster from the Powertrain Control Module
(PCM)

over

the

Programmable

Communications

Interface (PCI) data bus. The engine coolant temper-
ature gauge is an air core magnetic unit that receives
battery current on the instrument cluster electronic
circuit board through the fused ignition switch out-
put (run-start) circuit whenever the ignition switch is
in the On or Start positions. The cluster is pro-
grammed to move the gauge needle back to the low
end of the scale after the ignition switch is turned to
the Off position. The instrument cluster circuitry
controls the gauge needle position and provides the
following features:

• Engine Temperature Message - Each time

the cluster receives a message from the PCM indicat-
ing the engine coolant temperature is between the
low end of normal [about 54° C (130° F) for gasoline
engines, or 65° C (149° F) for diesel engines] and the
high end of normal [about 129° C (264° F) for gaso-
line engines, or 120° C (248° F) for diesel engines],
the gauge needle is moved to the actual temperature
position on the gauge scale.

• Engine Temperature Low Message - Each

time the cluster receives a message from the PCM
indicating the engine coolant temperature is below
the low end of normal [about 54° C (130° F) for gas-
oline engines, or 65° C (149° F) for diesel engines],
the gauge needle is held at the “C” increment at the
far left end of the gauge scale. The gauge needle
remains at the far left end of the scale until the clus-
ter receives a message from the PCM indicating that
the engine temperature is above about 54° C (130° F)
for gasoline engines, or 65° C (149° F) for diesel
engines, or until the ignition switch is turned to the
Off position, whichever occurs first.

• Engine Temperature High Message - Each

time the cluster receives a message from the PCM
indicating the engine coolant temperature is above
about 122° C (251° F) for gasoline engines, or 108° C
(226° F) for diesel engines, the gauge needle is moved
to the appropriate position on the gauge scale, the
check gauges indicator is illuminated, and a single
chime tone is sounded. The check gauges indicator
remains illuminated until the cluster receives a mes-
sage from the PCM indicating that the engine tem-
perature is below about 119° C (246° F) for gasoline
engines, or 104° C (219° F) for diesel engines, or
until the ignition switch is turned to the Off position,
whichever occurs first. The chime tone feature will
only repeat during the same ignition cycle if the
check gauges indicator is cycled off and then on
again by the appropriate engine temperature mes-
sages from the PCM.

• Message Failure - If the cluster fails to receive

an engine temperature message, it will hold the
gauge needle at the last indication until a new mes-
sage is received, or until the ignition switch is turned
to the Off position, whichever occurs first.

• Actuator Test - Each time the cluster is put

through the actuator test, the gauge needle will be
swept to several calibration points on the gauge scale
in a prescribed sequence in order to confirm the func-
tionality of the gauge and the cluster control cir-
cuitry.

The PCM continually monitors the engine coolant

temperature sensor to determine the engine operat-
ing temperature. The PCM then sends the proper
engine coolant temperature messages to the instru-
ment cluster. For further diagnosis of the engine cool-
ant temperature gauge or the instrument cluster
circuitry that controls the gauge, (Refer to 8 - ELEC-
TRICAL/INSTRUMENT CLUSTER - DIAGNOSIS
AND TESTING). If the instrument cluster turns on
the check gauges indicator due to a high engine tem-
perature gauge reading, it may indicate that the
engine or the engine cooling system requires service.
For proper diagnosis of the engine coolant tempera-
ture sensor, the PCM, the PCI data bus, or the mes-
sage inputs to the instrument cluster that control the
engine coolant temperature gauge, a DRBIII

t scan

tool is required. Refer to the appropriate diagnostic
information.

FUEL GAUGE

DESCRIPTION

A fuel gauge is standard equipment on all instru-

ment clusters. The fuel gauge is located in the lower
right quadrant of the instrument cluster, below the
oil pressure gauge. The fuel gauge consists of a mov-
able gauge needle or pointer controlled by the instru-
ment cluster circuitry and a fixed 90 degree scale on
the cluster overlay that reads left-to-right from E (or
Empty) to F (or Full). An International Control and
Display Symbol icon for “Fuel” is located on the clus-
ter overlay, in the center of the gauge directly above
the hub of the gauge needle. An arrowhead pointed
to the left side of the vehicle is imprinted on the clus-
ter overlay next to the “Fuel” icon in the fuel gauge
to provide the driver with a reminder as to the loca-
tion of the fuel filler access. The fuel gauge graphics
are white against a black field except for a single red
graduation at the low end of the gauge scale, making
them clearly visible within the instrument cluster in
daylight. When illuminated from behind by the panel
lamps dimmer controlled cluster illumination lighting
with the exterior lamps turned On, the white graph-
ics appear blue-green and the red graphics appear

INSTRUMENT CLUSTER

8J - 19

ENGINE TEMPERATURE GAUGE (Continued)

red. The orange gauge needle is internally illumi-
nated. Gauge illumination is provided by replaceable
incandescent bulb and bulb holder units located on
the instrument cluster electronic circuit board. The
fuel gauge is serviced as a unit with the instrument
cluster.

OPERATION

The fuel gauge gives an indication to the vehicle

operator of the level of fuel in the fuel tank. This
gauge is controlled by the instrument cluster circuit
board based upon cluster programming and elec-
tronic messages received by the cluster from the
Powertrain Control Module (PCM) over the Program-
mable Communications Interface (PCI) data bus. The
fuel gauge is an air core magnetic unit that receives
battery current on the instrument cluster electronic
circuit board through the fused ignition switch out-
put (run-start) circuit whenever the ignition switch is
in the On or Start positions. The cluster is pro-
grammed to move the gauge needle back to the low
end of the scale after the ignition switch is turned to
the Off position. The instrument cluster circuitry
controls the gauge needle position and provides the
following features:

• Percent Tank Full Message - Each time the

cluster receives a message from the PCM indicating
the percent tank full, the cluster programming
applies an algorithm to calculate the proper gauge
needle position, then moves the gauge needle to the
proper position on the gauge scale. The algorithm is
used to dampen gauge needle movement against the
negative effect that fuel sloshing within the fuel tank
can have on accurate inputs from the fuel tank send-
ing unit to the PCM.

• Less Than 12.5 Percent Tank Full Message -

Each time the cluster receives messages from the
PCM indicating the percent tank full is 12.5 (one-
eighth) or less for 10 consecutive seconds and the
vehicle speed is zero, or for 60 consecutive seconds
and the vehicle speed is greater than zero, the gauge
needle is moved to the proper position on the gauge
scale, the low fuel indicator is illuminated, and a sin-
gle chime tone is sounded. The low fuel indicator
remains illuminated until the cluster receives mes-
sages from the PCM indicating that the percent tank
full is greater than 12.5 (one-eighth) for 10 consecu-
tive seconds and the vehicle speed is zero, or for 60
consecutive seconds and the vehicle speed is greater
than zero, or until the ignition switch is turned to
the Off position, whichever occurs first. The chime
tone feature will only repeat during the same igni-
tion cycle if the low fuel indicator is cycled off and
then on again by the appropriate percent tank full
messages from the PCM.

• Less Than Empty Percent Tank Full Mes-

sage - Each time the cluster receives a message from
the PCM indicating the percent tank full is less than
empty, the gauge needle is moved to the far left (low)
end of the gauge scale and the low fuel indicator is
illuminated immediately. This message would indi-
cate that the fuel tank sender input to the PCM is a
short circuit.

• More Than Full Percent Tank Full Message

- Each time the cluster receives a message from the
PCM indicating the percent tank full is more than
full, the gauge needle is moved to the far left (low)
end of the gauge scale and the low fuel indicator is
illuminated immediately. This message would indi-
cate that the fuel tank sender input to the PCM is an
open circuit.

• Message Failure - If the cluster fails to receive

a percent tank full message, it will hold the gauge
needle at the last indication until a new message is
received, or until the ignition switch is turned to the
Off position, whichever occurs first.

• Actuator Test - Each time the cluster is put

The PCM continually monitors the fuel tank send-

ing unit, then sends the proper messages to the
instrument cluster. For further diagnosis of the fuel
gauge or the instrument cluster circuitry that con-
trols the gauge, (Refer to 8 - ELECTRICAL/INSTRU-
MENT CLUSTER - DIAGNOSIS AND TESTING).
For proper diagnosis of the fuel tank sending unit,
the PCM, the PCI data bus, or the message inputs to
the instrument cluster that control the fuel gauge, a
DRBIII

t scan tool is required. Refer to the appropri-

ate diagnostic information.

GEAR SELECTOR INDICATOR

DESCRIPTION

An electronic automatic transmission gear selector

indicator is standard factory-installed equipment on
this model, when it is also equipped with an optional
automatic transmission. The gear selector indicator
information is displayed in a Vacuum-Fluorescent
Display (VFD), which is visible through a small win-
dow cutout located in the lower right quadrant of the
cluster overlay. The gear selector indicator displays
the following characters from left to right: “P,” “R,”
“N,” “D,” “2,” and “1.” Respectively, these characters
represent the park, reverse, neutral, drive, second
gear, and first gear positions of the transmission gear
selector lever on the steering column. The VFD illu-

8J - 20

INSTRUMENT CLUSTER

FUEL GAUGE (Continued)

minates a rectangular box around the character that
represents the currently selected lever position.

During daylight hours (exterior lamps Off) the gear

selector indicator VFD is illuminated at full bright-
ness for clear visibility. At night (exterior lamps are
On) the VFD lighting level is adjusted with the other
cluster illumination lamps using the panel lamps
dimmer thumbwheel on the headlamp switch. How-
ever, a “Parade” mode position of the panel lamps
dimmer thumbwheel allows the VFD to be illumi-
nated at full brightness while the exterior lamps are
turned On during daylight hours. The gear selector
indicator VFD is serviced as a unit with the instru-
ment cluster.

OPERATION

The electronic gear selector indicator gives an indi-

cation to the vehicle operator of the transmission
gear that has been selected with the automatic trans-
mission gear selector lever. This gauge is controlled
by the instrument cluster circuit board based upon
cluster programming. The cluster circuitry automati-
cally configures itself for the proper automatic trans-
mission

model

based

upon

the

hard

wired

transmission range sensor mux circuit input to the
cluster. Each time the cluster is disconnected from
battery current for more than about five minutes, it
must configure itself again for the automatic trans-
mission model that is in the vehicle when it is recon-
nected to battery current. The gear selector indicator
information is displayed by a dedicated Vacuum Flu-
orescent Display (VFD) on the instrument cluster
electronic circuit board, and the VFD will not display
the gear selector indicator information after the igni-
tion switch is turned to the Off position. The instru-
ment cluster circuitry configures the gear selector
indicator VFD based upon the following inputs from
the transmission range sensor:

• Open Circuit - If the transmission range sensor

mux circuit is open, the cluster circuitry controls the
gear selector indicator display based upon electronic
messages received from the electronic Transmission
Control Module (TCM) over the Programmable Com-
munications Interface (PCI) data bus. If the input is
open circuit and no electronic messages are received
from the TCM within two seconds, the instrument
cluster circuitry will cycle the indicated gear selector
position from P, to R, to N, to D to 2 repeatedly and
continuously until the condition is resolved or until
the ignition switch is turned to the Off position,
whichever occurs first.

• Resolved Circuit - If the transmission range

sensor mux circuit is resolved, the cluster circuitry
controls the gear selector indicator display based
upon the resistance value of the hard wired input
from the transmission range sensor. If the cluster

has configured itself for the transmission range sen-
sor input and detects a short to ground in the trans-
mission range sensor mux input, the cluster will
indicate all positions in the VFD; or, if this input is
open circuit, the cluster will blink all positions in the
VFD. The VFD display for the short-to-ground and
open circuit conditions will continue until the condi-
tion is resolved or until the ignition switch is turned
to the Off position, whichever occurs first.

• Actuator Test - Each time the cluster is put

through the actuator test, the VFD will display all of
its characters at once, then step through each char-
acter segment individually during the VFD portion of
the test to confirm the functionality of the VFD and
the cluster control circuitry.

On models with a TCM, the TCM continually mon-

itors the transmission range sensor, then sends the
proper gear selector indicator messages to the instru-
ment cluster. On models without a TCM, the instru-
ment cluster continually monitors the hard wired
transmission range sensor multiplexed input. For
further diagnosis of the gear selector indicator or the
instrument cluster circuitry that controls this func-
tion, (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). On mod-
els without a TCM, for further diagnosis of the trans-
mission

range

sensor,

(Refer

TRANSMISSION/TRANSAXLE/AUTOMATIC

42RE/TRANSMISSION RANGE SENSOR - DIAG-
NOSIS AND TESTING) or (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC

46RE/

TRANSMISSION RANGE SENSOR - DIAGNOSIS
AND TESTING). On models with a TCM, for proper
diagnosis of the transmission range sensor, the TCM,
the PCI data bus, or the message inputs to the
instrument cluster that control the gear selector indi-
cator, a DRBIII

t scan tool is required. Refer to the

appropriate diagnostic information.

HIGH BEAM INDICATOR

DESCRIPTION

A high beam indicator is standard equipment on

all instrument clusters. The high beam indicator is
located near the upper edge of the instrument cluster
overlay, between the tachometer and the speedome-
ter. The high beam indicator consists of a stenciled
cutout of the International Control and Display Sym-
bol icon for “High Beam” in the opaque layer of the
instrument cluster overlay. The dark outer layer of
the overlay prevents the indicator from being clearly
visible when it is not illuminated. A blue lens behind
the cutout in the opaque layer of the overlay causes
the icon to appear in blue when it is illuminated
from behind by a replaceable incandescent bulb and

INSTRUMENT CLUSTER

8J - 21

GEAR SELECTOR INDICATOR (Continued)

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