Part 1 0F 2
INSTRUMENT PANEL SYSTEMThe instrument panel serves as the command center 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, lighting systems, safety systems and many other comfort or convenience items. 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. See the owner's manual in the vehicle glove box for more information on the features, use and operation of all of the instrument panel components and systems.
This is responsible for covering service information for the vehicle instrument panel systems. However, complete service information coverage for all of the systems and components housed in the instrument panel in a single of the service would not be practical. Therefore, the service information for any component will be designated to cover the vehicle system that the component belongs to, even though the component is mounted on or in the instrument panel. If you cannot locate a listing for the component or system you are servicing in the table of contents, or if you are uncertain as to which vehicle system a component belongs to, it is suggested that you refer to the alphabetical Component and System Index found at the back of this service.
INSTRUMENT PANEL
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 riveted 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 construction provides improved energy absorption which, in conjunction with the dual airbag modules and seat belts, helps to improve occupant protection.
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 or heating and air conditioning components can be accessed without complete instrument panel removal. If necessary, the instrument panel can be removed from the vehicle as an assembly.
Removal of the instrument cluster bezel allows access to the instrument cluster, the heating and air conditioning controls, and the radio. Removal of the instrument cluster assembly allows access to the individual illumination and indicator lamp bulbs, and the instrument cluster wiring.
Removal of the steering column opening cover provides access to the steering column mounts, the steering column wiring, the junction block (removal of a snap-fit fuse access panel on the left end of the instrument panel allows access to the fuses and circuit breakers), the [1][2]Central Timer Module ([1][2]CTM), the Infinity speaker filter choke and relay unit, much of the instrument panel wiring, and the gear selector indicator cable (automatic transmission).
Removal of the glove box provides access to the passenger side airbag module, the glove box lamp and switch, the radio antenna coaxial cable, the heating and air conditioning vacuum harness connector, and additional instrument panel wiring.
INSTRUMENT CLUSTER
A single instrument cluster is offered on this model. This cluster is an electromechanical unit that utilizes integrated circuitry and information carried on the Chrysler Collision Detection (CCD) data bus network for control of all gauges and many of the indicator lamps. This cluster also incorporates a digital Vacuum Fluorescent Display (VFD) for the odometer/trip odometer display functions. Some variations of these clusters exist due to optional equipment and regulatory requirements.
This cluster includes the following analog gauges:
- Coolant temperature gauge
- Fuel gauge
- Oil pressure gauge
- Speedometer
- Tachometer
- Voltmeter.
This cluster also includes provisions for the following indicator lamps:
- Airbag indicator lamp
- Anti-lock Brake System (ABS) lamp
- Brake warning lamp
- Check gauges lamp
- Cruise-on indicator lamp (programmable)
- Four-wheel drive indicator lamp
- Headlamp high beam indicator lamp
- Low fuel warning lamp
- Low washer fluid warning lamp
- Malfunction Indicator Lamp (MIL)
- Overdrive-off indicator lamp (automatic transmission - programmable)
- Seat belt reminder lamp
- Service Reminder Indicator (SRI) lamp (Maintenance Required - for certain heavy-duty emissions cycle engines)
- Transmission oil temperature warning lamp (automatic transmission - programmable)
- Turn signal indicator lamps
- Upshift indicator lamp (manual transmission - programmable)
- Wait-to-start indicator lamp (diesel engine)
- Water-in-fuel indicator lamp (diesel engine)
The instrument cluster also includes a provision for mounting the automatic transmission gear selector indicator in the lower right corner of the cluster. Models equipped with a manual transmission have a block-out plate installed in place of this indicator,
The instrument cluster circuitry has a self-diagnostic actuator test capability, which will test each of the CCD bus message-controlled functions of the cluster by lighting the appropriate indicator lamps and positioning the gauge needles at several predetermined locations on the gauge faces in a prescribed sequence. For more information on this function, refer to Instrument Cluster in the Diagnosis and Testing.
The instrument cluster circuitry also sends chime tone requests over a hard wired circuit to the Central Timer Module (CTM) when it monitors certain conditions or inputs. The [1][2]CTM replaces the chime or buzzer module. Refer to Chime Warning System in the Description and Operation of Chime/Buzzer Warning Systems for more information on this feature.
The instrument cluster for this model is serviced only as a complete unit. If a cluster gauge or the cluster circuit board are faulty, the entire cluster must be replaced. The cluster lens, the cluster hood, the rear cluster housing cover, and the incandescent lamp bulbs and holders are available for service replacement.
The instrument cluster is an electromechanical unit that contains integrated circuitry and internal programming to perform a variety of functions. The instrument cluster circuitry monitors hard-wired switch inputs, as well as message inputs received from other vehicle electronic modules on the Chrysler Collision Detection (CCD) data bus network.
The instrument cluster uses these many inputs along with its internal programming to provide hard-wired chime tone requests to the Central Timer Module (CTM), which performs the functions of the chime warning module on this model. The instrument cluster circuitry also has a self-diagnostic capability. Refer to Instrument Cluster in the Diagnosis and Testing of Instrument Panel Systems for more information on this feature.
The only instrument cluster diagnosis found in this consists of confirming the viability of the hard- wired chime request circuit between the instrument cluster circuitry and the [1][2]CTM, and diagnosis of the hard-wired seat belt switch input to the instrument cluster. For diagnosis of the CCD data bus and the data bus message inputs, a DRB scan tool and the proper Diagnostic Procedures are recommended.
Refer to Instrument Cluster in the Removal and Installation of Instrument Panel Systems for the instrument cluster service procedures. Refer to the Diagnosis and Testing of Instrument Panel systems for more information on the remaining hard-wired instrument cluster inputs. The instrument cluster chime warning circuitry cannot be repaired and, if faulty or damaged, the instrument cluster assembly must be replaced.
GAUGE
With the ignition switch in the On or Start positions, voltage is supplied to all gauges through the instrument cluster electronic circuit board. With the ignition switch in the OFF position, voltage is not supplied to the gauges. The gauges do not accurately indicate any vehicle condition unless the ignition switch is in the On or Start positions.
All of the instrument cluster gauges, except the odometer, are air core magnetic units. Two fixed electromagnetic coils are located within the gauge. These coils are wrapped at right angles to each other around a movable permanent magnet. The movable magnet is suspended within the coils on one end of a shaft. The gauge needle is attached to the other end of the shaft.
One of the coils has a fixed current flowing through it to maintain a constant magnetic field strength. Current flow through the second coil changes, which causes changes in its magnetic field strength. The current flowing through the second coil is changed by the instrument cluster electronic circuitry in response to messages received on the Chrysler Collision Detection (CCD) data bus network.
The gauge needle moves as the movable permanent magnet aligns itself to the changing magnetic fields created around it by the electromagnets. The instrument cluster circuitry is programmed to move all of the gauge needles back to the low end of their respective scales after the ignition switch is turned to the OFF position.
INDICATOR LAMP
Indicator lamps are located in the instrument cluster and are served by the cluster circuit board and connectors. Many of the indicator lamps in the instrument cluster are controlled by the instrument cluster circuitry in response to messages received over the Chrysler Collision Detection (CCD) data bus network.
The four-wheel drive indicator lamp, headlamp high beam indicator lamp, low washer fluid warning lamp, turn signal indicator lamps, and wait-to-start indicator lamp are hard wired. The seat belt reminder lamp is controlled by the instrument cluster programming and by CCD data bus messages from the Airbag Control Module (ACM). The brake warning lamp is controlled by a hard wired input from the park brake switch and by CCD data bus messages from the Controller Anti-lock Brake (CAB). The instrument cluster circuitry uses CCD data bus messages from the Powertrain Control Module (PCM), Engine Control Module (ECM), ACM, and CAB to control all of the remaining indicator lamps.
In addition, certain indicator lamps in this instrument cluster are programmable. This feature allows those indicator lamps to be activated or deactivated with a DRB III scan tool through the instrument cluster electronic circuitry for compatibility with certain optional equipment. The programmable indicator lamps for this model include the cruise-on indicator lamp, the overdrive-off indicator lamp, the transmission oil temperature warning lamp and the upshift indicator lamp.
Except for the cruise-on indicator lamp, headlamp high beam indicator lamp, turn signal indicator lamps and the wait-to-start indicator lamp, each of the indicator lamps in the instrument cluster is illuminated by a dedicated Light-Emitting Diode (LED). If an LED should fail, the entire instrument cluster must be replaced. The cruise-on indicator lamp is part of the odometer VFD display. The headlamp high beam indicator lamp, turn signal indicator lamp and the wait-to-start indicator lamp use incandescent bulbs. The incandescent indicator lamps have a replaceable bulb and bulb holder.