INSTRUMENT CLUSTER FUNCTION
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• The instrument cluster is a hybrid electronic cluster (HEC). The instrument cluster performs transmission and reception of information via standard corporate protocol (SCP) (J1850) or CAN. To perform diagnosis, it is necessary to understand the following items:
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― Input signal origin
― All information necessary in order for equipment to operate.
― Which module (s) receive (s) the input or command message.
― Does the module which received the input, control the output of the equipment, or does it output a message over the SCP (J1850) or CAN line to another module?
― Which module controls the output of the feature.
• The instrument cluster diagnoses and verifies that all warning/indicator miniature bulbs and monitored systems are functioning correctly. When the ignition switch is in the ON position with the engine off, the following warning indicators will illuminate:
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― MIL
― Generator warning light
― Oil pressure warning light
― ABS warning light
― Seat belt warning light
― Air bag system warning light
― Brake system warning light
― Fuel-level warning light
― Security light (vehicles with immobilizer system)
― O/D OFF indicator light
Gauge Indication System
• The gauge indication systems use stepping motor-type gauges mounted in the instrument cluster. No adjustment, calibration, or maintenance is necessary for any of the gauges. The gauges cannot be installed separately.
Speedometer
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• The instrument cluster receives the vehicle speed signal from the powertrain control module (PCM) via the SCP (J1850) or CAN line network. If the instrument cluster receives no signal, the speedometer will default to 0.0 km/h (0.0 mph).
Odometer
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• The vehicle is equipped with two odometers. The primary odometer shows cumulative distance. The second odometer is the trip and tenths odometer.
Tachometer
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• The tachometer is electrically operated and indicates engine speed in a range of 0 to 8,000 rpm. The tachometer receives the signal via the SCP (J1850) or CAN line from the PCM. If the rpm information sent to the instrument cluster is invalid or missing, the instrument cluster will default the tachometer to 0.0 rpm.
Fuel gauge
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• The instrument cluster receives the fuel signal via hard-wired circuitry from the fuel pump unit. The fuel pump unit changes resistance according to the amount of fuel in the fuel tank and varies the current flow through the fuel gauge. A low resistance will result in a lower gauge indication, while a high resistance will result in a higher gauge indication. The fuel gauge is controlled by the instrument cluster microprocessor and varies the position according to data received from the fuel pump unit.
Water temperature gauge
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• The instrument cluster receives the engine coolant temperature signal from the PCM via the SCP (J1850) or CAN line and displays the information on the water temperature gauge. If the instrument cluster receives no signal the water temperature gauge will default to the COLD position.
Oil pressure warning light
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• The oil pressure warning light is hard-wired to the oil pressure switch. The oil pressure switch is a normally closed switch. When the engine is off or has no oil pressure the switch is closed, providing a ground path to turn on the light. When the engine is running and there is oil pressure present, the switch is opened and no ground is provided.
Generator warning light
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• The generator warning light is hard-wired to the generator and illuminates when the generator output is insufficient to maintain the battery charged.
Air bag system warning light
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• The air bag warning light is hard-wired to the SAS control module. When the air bag system is operating correctly, the air bag warning light illuminates for approx. 6 s when the ignition switch is turned to the ON position. It only illuminates after starting if a malfunction is present in the air bag system.
Malfunction indicator lamp
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• When the ignition switch is in the ON position the bulb will diagnose. During vehicle operation, the malfunction indicator lamp (MIL) illuminates when the PCM has detected a malfunction. If a malfunction is detected the PCM sends a signal to the instrument cluster via the SCP (J1850) or CAN line and turns on the MIL lamp.
High-beam indicator light
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• The high beam indicator is hard-wired to the steering column light switch and illuminates when the headlights are placed in the high beam position or the flash-to-pass position.
Turn indicator light
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• The RH or LH turn indicator lights are hard-wired to the steering column light switch and illuminate intermittently relative to the position of the turn signal switch on the steering column.
Brake system warning light
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• The brake system warning light has multiple functions. It illuminates when the parking brake is applied, when the brake fluid level is low or when a fault is detected in the anti-lock brake system (ABS). It utilizes both hard-wired circuitry and the instrument cluster microprocessor. The bulb diagnosis occurs for approx. 3 s after turning the ignition switch to the ON position. The brake system warning light will go out following diagnosis if the brake fluid level is correct, the parking brake is released, and no ABS malfunction is detected.
ABS warning light (with ABS)
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• The ABS warning light illuminates when the ABS HU/CM detects a malfunction in the system. If a malfunction is detected, the ABS HU/CM sends a signal to the instrument cluster and the instrument cluster illuminates the ABS warning light.
Seat belt warning light
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• The seat belt warning light illuminates when the driver seat belt is not fastened. The driver seat belt retractor switch (part of the retractor) is hard-wired to the instrument cluster and provides the input into the instrument cluster signaling when the seat belt is connected. The instrument cluster then illuminates the bulb depending on the seat belt retractor position.
Security light (with immobilizer system)
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• The security light located in the instrument cluster is controlled by a signal sent via the SCP (J1850) or CAN line from the PCM.
4WD indicator light (4WD)
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• The 4WD indicator light is hard-wired to the 4WD control module and illuminates when the four-wheel drive is selected.
Door ajar warning light
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• The door ajar indicator is hard-wired to the generic electronic module (GEM) and will illuminate when any of the doors, or the liftgate, are opened.
Fuel-level warning light
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• The fuel-level warning light diagnoses for 3 s when the ignition is turned to the ON position. The indicator will then remain on if the fuel level is less than approx. 10 L.
O/D OFF indicator light
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• The O/D OFF indicator light will illuminate when the transaxle overdrive has been turned off. The instrument cluster receives a switch status signal via the SCP (J1850) or CAN line from the PCM.
Selector indicator light
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• The instrument cluster selector indicator light is a liquid crystal display (LCD) that displays the transmission range selected. Two sets of input signals are necessary for the indicator to operate correctly. The instrument cluster receives the transaxle range signal via hard-wired circuitry from the transmission range selector and displays the appropriate range in the LCD. The park interlock solenoid provides the second input. If the park interlock input is not present, the P range will not be highlighted in the LCD display.
Cruise control indicator light
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• The cruise control indicator light will illuminate when the cruise control system is operated.
Warning Systems
• The warning chime module is built into the instrument cluster. The system consists of the following components:
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― Instrument cluster
― Seat belt retractor switch, an integral part of the driver seat belt retractor
― Door lock switch
― Ignition switch
― Light switch
Seat belt warning chime
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• The seat belt warning chime alerts that the seat belt is not fastened. The seat belt chime will sound when the driver seat belt is not fastened and the ignition switch is turned from the off to the ON or START position. The seat belt warning chime will stop when the seat belt is fastened or when the ignition is turned off.
• The seat belt warning chime input signals are:
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― The ignition switch position
― Driver’s seat belt retractor switch
R-position warning alarm
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• The reverse warning chime sounds when the vehicle is in reverse gear while the ignition switch is in the ON position.
• The reverse warning chime inputs signals are:
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― Ignition switch in the ON position
― Transaxle range switch
Door ajar warning chime
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• The door ajar warning chime sounds when the front driver side door or front passenger side door becomes ajar while the ignition switch is in the ON position.
• The door ajar warning chime will stop when the door is closed or when the ignition switch is turned off.
• The door ajar warning chime input signals are:
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― Ignition switch in the ON position
― Door switch
Headlight on warning chime
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• The headlight on warning chime sounds if the parking lamps or the headlights are left on after the key has been removed from the ignition switch lock cylinder and the driver door is opened.
• The warning chime will stop when any of the above conditions are removed.
• The headlight-on warning chime input signals are:
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― Ignition switch
― Light switch
― Door switch (driver-side)
Key in ignition warning chime
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• The warning sounds if the key is left in the ignition switch lock cylinder when the driver door is opened and the ignition switch is in the OFF or ACC position.
• The warning chime will stop when any of the above conditions are removed.
• The key in ignition warning chime input signals are:
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― Ignition switch
― Door switch (driver-side)