Dodge Ram 2004, Service Manual

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ignition/battery as-well-as shorted to ground
indicates that two actuator driver circuits are
shorted together.
•
When the test returns passed, then troubleshoot-
ing should proceed to clearing faults and running
the HVAC Door Recalibration system test as a
final check of system health.
3.10 INSTRUMENT CLUSTER
The DR Instrument Cluster is a new type of
control module that includes the hardware and
software necessary to function as the cluster and
the body control module. The Instrument Cluster
houses the Speedometer, Tachometer, Fuel gauge,
Coolant Temperature gauge, Oil Pressure gauge,
and the Voltage gauge. The cluster positions all of
the gauges using PCI bus messages received from
the PCM. The cluster contains certain warning
indicators, depending on engine type and options.
Some of the indicators are hardwire inputs and
some indicators are controlled via PCI bus mes-
sages. The warning chime tone generator is con-
tained within the cluster. The cluster includes a
vacuum fluorescent (VF) display for the PRNDL,
Total and Trip Odometers. The VF will also display
warning messages such as door ajar, low washer
fluid level, engine hours, and no bus communica-
tions. The cluster has the ability to set and store
DTCs, communicate on the PCI bus, display engine
information, and display certain inputs using the
DRBIII
t
.
The following systems are controlled either com-
pletely by the Instrument Cluster or in conjunction
with other inputs received by hardwire or via the
PCI bus:
•
Audible Warnings
• Brake Lamp Control
• Brake Transmission Shift Interlock (BTSI)
• Cargo Lamp Control
• Central Locking
•
Door Lock Inhibit
• Enhanced Accident Response
•
Exterior Lighting Control
• Exterior Lighting Fail-Safe
•
Heated Seat Control
• Horn Control
• Interior Lamp Control
• Interior Lamps - Enhanced Accident Response
• Interior Lamps Load Shedding
•
Lamp Out Indicator Control
• Panel Lamps Dimming Control
•
Parade Mode
• Power Locks
• Remote Keyless Entry (RKE)
• Remote Radio Switch Interface
•
Rolling Door Locks
• Turn Signal and Hazard Warning Lamp Control
•
Vacuum Fluorescent Display Synchronization
• Vehicle Theft Security System (VTSS)
CAUTION: Instrument clusters used in this
model automatically configure themselves
for
compatibility with the features and
optional equipment in the vehicle in which
they are initially installed. The instrument
cluster
is programmed to do this by
embedding the Vehicle Identification Number
(VIN) and other information critical to proper
cluster operation in electronic memory. This
embedded information is learned through
electronic messages received from other
electronic modules in the vehicle over the
Programmable
Communications Interface
(PCI) data bus, and through certain hard
wired inputs received when the cluster is
connected to the vehicle electrically.
Once configured, the instrument cluster
memory may be irreparably damaged and
certain irreversible configuration errors may
occur if the cluster is connected electrically to
another vehicle; or, if an electronic module
from
another vehicle is connected that
provides data to the instrument cluster
(including odometer values) that conflicts with
that which was previously learned and stored.
Therefore, the practice of exchanging
(swapping) instrument clusters and other
electronic modules in this vehicle with those
removed from another vehicle must always
be avoided. Failure to observe this caution
may result in instrument cluster damage,
which is not reimbursable under the terms of
*
the product warranty. Service replacement
instrument clusters are provided with the
correct VIN, and the certified odometer and
engine hours values embedded in cluster
memory, but will otherwise be automatically
configured for compatibility with the features
and optional equipment in the vehicle in
which they are initially installed.
15
GENERAL INFORMATION