Instrument Cluster - Description
DESCRIPTION
The instrument cluster (2) is located in the instrument panel (1) above the steering column opening and includes the hardware and software necessary to serve as the electronic body control module also known as the Cab Compartment Node (CCN). The remainder of the instrument cluster, including the mounts and the electrical connections, are concealed within the instrument panel behind the cluster bezel. Besides analog gauges and indicators, the CCN module incorporates a single unit for displaying odometer/trip odometer information, engine hours, several warning or reminder indications and certain diagnostic information. The instrument cluster for this vehicle also.
The instrument cluster gauges and indicators are visible through a dedicated opening in the cluster bezel on the instrument panel and are protected by a clear plastic cluster lens that is integral to a cluster lens and hood unit (2). Just behind the cluster lens is the cluster hood. The cluster hood serves as a visor and shields the face of the cluster from ambient light and reflections to reduce glare. A black plastic odometer/trip odometer switch button protrudes through dedicated holes in the cluster lens, located near the lower edge of the cluster just to the left of the speedometer. The molded plastic lens and hood unit has three integral mounting tabs, one each on the lower outboard corners and one on the upper center of the unit. These mounting tabs are used to secure the CCN to the molded plastic instrument panel cluster carrier with three screws.
The rear of the cluster housing and the CCN electronic circuitry are protected by a molded plastic rear cover (1), which is secured to the cluster housing with molded plastic clips, while eight similar clips around the outside perimeter of the rear cover secure it to the cluster lens and hood unit. The rear cover includes clearance holes for the cluster connector receptacles. The connector receptacles on the back of the cluster electronic circuit board connect the CCN to the vehicle electrical system through three take outs with connectors from the instrument panel wire harness.
Sandwiched between the rear cover and the lens and hood unit is the cluster housing (3). The molded plastic cluster housing serves as the carrier for the cluster circuit board and circuitry, the cluster connector receptacles, the gauges, a Light Emitting Diode (LED) for each cluster indicator, an audible tone transducer, the cluster overlay, the gauge pointers, the odometer/trip odometer switch.
The cluster overlay is a laminated plastic unit. The dark, visible, outer surface of the overlay is marked with all of the gauge dial faces and graduations, but this layer is also translucent. The darkness of this outer layer prevents the cluster from appearing cluttered or busy by concealing the cluster indicators that are not illuminated, while the translucence of this layer allows those indicators and icons that are illuminated to be readily visible. The underlying layer of the overlay is opaque and allows light from the LED for each of the various indicators and the LED general illumination behind it to be visible through the outer layer of the overlay only through predetermined stencil-like cutouts. A rectangular opening in the overlay between the Tachometer and the Speedometer through which the Liquid Crystal Display (LCD) unit can be viewed.
Several versions of the CCN module are offered on this vehicle. These versions accommodate all of the variations of optional equipment and regulatory requirements for the various markets in which the vehicle will be offered. The microprocessor-based CCN utilizes integrated circuitry and information carried on the Controller Area Network (CAN) data bus along with several hardwired analog and multiplexed inputs to monitor sensors and switches throughout the vehicle. In response to those inputs, the internal circuitry and programming of the CCN allow it to control and integrate many electronic functions and features of the vehicle through both hardwired outputs and the transmission of electronic message outputs to other electronic modules in the vehicle over the CAN data bus. Communication - Description.
Besides typical instrument cluster gauge and indicator support, the electronic functions and features that the CCN supports or controls include the following:
- Audible Warnings - The CCN electronic circuit board is equipped with an audible tone transducer and programming that allows it to provide various audible alerts to the vehicle operator, including chime tones and beep tones and, emulates the sound of a conventional turn signal or hazard warning flasher. Chime/Buzzer - Description.
- Brake Lamp Control - The CCN provides electronic brake lamp request messages to the Totally Integrated Power Module (TIPM) located in the engine compartment near the battery for brake lamp control, excluding control of the Center High Mounted Stop Lamp (CHMSL), which remains controlled by a direct hardwired output of the brake lamp switch.
- Cargo Lamp Control - The CCN provides direct control of cargo lamp operation with a load shedding (battery saver) feature which will automatically turn OFF the cargo lamp if it remains ON after a timed interval.
- Compass Mini Trip Computer Support - The CCN provides support for the optional Compass Mini Trip Computer (CMTC) by calculating average fuel economy, distance to empty and outside temperature values and storing trip odometer and elapsed ignition-ON time data. The CCN receives data and reset requests from the CMTC and transmits the appropriate information for the CMTC to display using electronic messaging.
- Electronic Transfer Case Interface - On vehicles equipped with an electronic four-wheel drive transfer case, the CCN monitors a hardwired multiplex input from the transfer case mode switch and then provides the appropriate electronic data bus messages to the TIPM for transfer case control. After the transfer case shift is completed, the TIPM provides an electronic message back to the CCN and the CCN responds by activating the appropriate 4WD indicators within the cluster or in the transfer case switch.
- Electronic Vehicle Information Center Support - The CCN provides support for the optional Electronic Vehicle Information Center (EVIC) and the Compass Mini Trip Computer (CMTC) by calculating average fuel economy, distance to empty and outside temperature values and storing trip odometer and elapsed ignition-ON time data.
- Enhanced Accident Response Support - The CCN monitors an input from the Occupant Restraint Controller (ORC) and, following an airbag deployment. The CCN monitors an input from the Powertrain Control Module (PCM) to automatically turn ON the interior lighting after an airbag deployment event, 10 seconds after the vehicle speed is zero. The interior lighting remains illuminated until the ignition switch is turned to the OFF position, at which time the interior lighting returns to normal operation and control. These Enhanced Accident Response System (EARS) features are each dependent upon a functional vehicle electrical system following the vehicle impact event.
- Exterior Lighting Control - The CCN provides electronic head lamp and park lamp request messages to the TIPM for the appropriate exterior lamp control of standard head and park lamps, as well as optional front fog lamps. This includes support for headlamp beam selection and the optical horn feature, also known as flash-to-pass.
- Exterior Lighting Fail-Safe - In the absence of a headlamp switch input, the CCN will turn ON the cluster general illumination lamps and provide electronic headlamp low beam and park lamp request messages to the TIPM for default exterior lamp operation. The TIPM will also provide default park lamp and headlamp low beam operation and the CCN will turn ON the cluster general illumination lighting at full intensity if there is a failure of the electronic data bus communication between the CCN and the TIPM.
- Fuel Level Data Support - The CCN provides a current source for and receives a Bus message input from the fuel level sending unit located on the fuel pump module in the fuel tank. The CCN uses this input to calculate the proper fuel gauge needle position and low fuel indicator operation. Based upon this input, the CCN also calculates fuel level, average fuel economy and distance to empty data, then uses electronic messaging to transmit this data over the CAN data bus for use by other electronic modules in the vehicle.
- Heated Seat Control - The CCN monitors inputs from the ignition switch and electronic engine speed messages from the Powertrain Control Module (PCM) to control a high side driver output to the heated seat switch Light Emitting Diode (LED) indicators. This input allows the heated seat switches to wake up the heated seat module if the switch is actuated. The CCN will de-energize the heated seat switch LED indicators, which deactivates the heated seat system, if the ignition switch is turned to any position except ON or START, or if the engine speed message indicates zero. Heated Seats - Description.
- Horn Control - The CCN monitors an input from the horn switch and provides electronic horn request messages to the TIPM for horn control.
- Instrument Panel Synchronization - The CCN monitors hardwired multiplexed inputs from the headlamp switch on the instrument panel, then transmits electronic panel lamp dimming level messages which allows all other electronic modules on the CAN data bus to coordinate their illumination intensity with that of the CCN. This includes a PARADE mode (also known as funeral mode) that allows all VFD units in the vehicle to be illuminated at full (daytime) intensity while driving during daylight hours with the exterior lamps turned ON.
- Interior Lamp Load Shedding - The CCN provides a battery saver feature which will automatically turn OFF all interior lamps and the cargo lamps if they remain ON after a timed interval of about five minutes.
- Interior Lighting Control - The CCN monitors inputs from the interior lighting switch, the door ajar switches, the cargo lamp switch, the reading lamp switches, and the Wireless Ignition Node (WIN) to provide courtesy lamp control. This includes support for timed illuminated entry with theater-style fade-to-OFF and courtesy illumination DEFEAT features.
- Panel Lamps Dimming Control - The CCN monitors hardwired multiplexed inputs from the headlamp switch on the instrument panel, then provides a hardwired 12-volt Pulse-Width Modulated (PWM) output that synchronizes the dimming level of all panel lamps dimmer controlled lamps with that of the cluster illumination lamps.
- Remote Keyless Entry - The CCN supports the optional Remote Keyless Entry (RKE) system features, including support for the RKE LOCK, UNLOCK (with optional driver-door-only unlock, and unlock-all-doors), PANIC, audible chirp, optical chirp, illuminated entry modes, an RKE programming mode, as well as optional Vehicle Theft Security System (VTSS) arming (when the proper VTSS arming conditions are met) and disarming.
- Remote Radio Switch Interface - The CCN monitors inputs from the optional remote radio switches and then provides the appropriate electronic data bus messages to the radio to select the radio or optional hands-free cellular system operating mode, volume control, preset station scan and station seek features.
- Turn Signal and Hazard Warning Lamp Control - The CCN monitors hard wired multiplexed inputs from the multi-function switch on the steering column, then provides electronic turn and hazard lamp request messages to the TIPM for turn and hazard lamp control. The CCN also provides an audible click at one of two rates to emulate normal and bulb out turn or hazard flasher operation based upon electronic lamp outage messages from the TIPM, and provides an audible turn signal ON chime warning if a turn is signalled continuously for more than about 1.6 kilometers (one mile) and the vehicle speed remains greater than about 24 kilometers-per-hour (15 miles-per-hour).
- Vehicle Theft Security System Control - The CCN monitors inputs from the door ajar switches, the ignition switch, and the WIN, then provides electronic horn and lighting request messages to the TIPM for the appropriate VTSS alarm output features.
- Wiper and Washer System Control - The CCN monitors LIN Bus inputs from the wiper and washer switches in the multi-function switch on the steering column, then provides electronic wiper and washer request messages to the TIPM for the appropriate wiper and washer system features. Wipers and Washers - Description.
The CCN houses either 4 or 6 analog gauges and has provisions for up to 27 indicators. Some of the CCN indicators are automatically configured when the CCN is connected to the vehicle electrical system for compatibility with certain optional equipment or equipment required for regulatory purposes in certain markets. While each CCN may have provisions for indicators to support every available option, the configurable indicators will not be functional in a vehicle that does not have the equipment that an indicator supports.
The CCN includes the following analog gauges:
- Engine Temperature Gauge (4)
- Fuel Gauge (3)
- Oil Pressure Gauge (16) - except ST models.
- Speedometer (5)
- Tachometer (1)
- Voltage Gauge (23) - except ST models.
The CCN includes the following LCD unit:
- Odometer/Trip Odometer/LCD/EVIC Display (20)
The CCN includes provisions for the following indicators:
- Airbag Indicator (29)
- Antilock Brake System (ABS) Indicator (30)
- Brake Indicator (25)
- Cargo Lamp Indicator (24)
- Change Oil Indicator (20) - on domestic market vehicles only, a textual message in LCD or in EVIC if so equipped.
- Charging Indicator (34) - ST models only.
- Cruise Indicator (20) - LCD. Also in Electronic Vehicle Information Center (EVIC) if so equipped.
- Door Ajar Indicator (20) - LCD. Also in Electronic Vehicle Information Center (EVIC) if so equipped.
- Electronic Stability Program (ESP)/Brake Assist System (BAS) Indicator (35) - Also in Electronic Vehicle Information Center (EVIC) if so equipped.
- Fog Lamp Indicator (31)
- Four-Wheel Drive (4WD) Indicator (10)
- Four-Wheel Drive Auto (4WD Auto) Indicator (11)
- Four-Wheel Drive Low (4 LOW) Indicator (7)
- Four-Wheel Drive Low (4 LOCK) Indicator (8)
- Gas Cap Indicator (20) - LCD Also in Electronic Vehicle Information Center (EVIC) if so equipped.
- High Beam Indicator (22)
- Low Fuel Indicator (21) - Also in Electronic Vehicle Information Center (EVIC) if so equipped.
- Low Oil Pressure Indicator (26) - Also in Electronic Vehicle Information Center (EVIC) if so equipped.
- Malfunction Indicator Lamp (MIL) (28)
- No Bus Indicator (20) - LCD. Also in.Electronic Vehicle Information Center (EVIC) if so equipped.
- No Fuse Indicator (20) - LCD. Also in.Electronic Vehicle Information Center (EVIC) if so equipped.
- Seat Belt Indicator (33)
- Security Indicator (15)
- Service Four-Wheel Drive (Serv 4WD) Indicator (12) - Also in Electronic Vehicle Information Center (EVIC) if so equipped.
- Tire Pressure Monitor (TPM) Indicator (27)
- Tow/Haul Indicator (14)
- Traction Control Indicator (13)
- Transmission Overtemp Indicator (32) - Also in Electronic Vehicle Information Center (EVIC) if so equipped.
- Transmission Range Indicator (19)
- Electronic Throttle Control (9) Also in.Electronic Vehicle Information Center (EVIC) if so equipped.
- Turn Signal (Right and Left) Indicators (2)
Each indicator in the CCN, except those located within the LCD unit, is illuminated by a dedicated LED that is soldered onto the CCN electronic circuit board. Cluster illumination is accomplished by dimmable LED back lighting, which illuminates each of the gauges for visibility when the exterior lighting is turned ON. The LED units are not available for service replacement and, if damaged or ineffective, the entire CCN must be replaced.
Hard wired circuitry connects the CCN to 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 connected to each other, to the vehicle electrical system and to the CCN 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 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.
The CCN module for this vehicle is serviced only as a complete unit. The CCN module cannot be adjusted or repaired. If a gauge, an LED indicator, the LCD unit, the electronic circuit board, the circuit board hardware, the cluster overlay, or the CCN housing are damaged or ineffective, the entire CCN module must be replaced. The cluster lens, hood and mask unit are available for separate service replacement.