Principles of Operation

PRINCIPLES OF OPERATION

The instrument cluster uses inputs that are both hardwired to individual components and messages that are sent from the other modules over the high speed or medium speed controller area networks (HS-CAN or MS-CAN) to control the warning chime functions.

It is very important to understand:
- where the input (command) originates.
- all the information (messages) necessary in order for a feature to operate.
- which module(s) receive(s) the input or command message.
- if the module that received the input (message) controls the output of the feature, or if it outputs a message over the CAN to another module.
- which module controls the output of the feature.

Instrument Cluster Messages

NOTE: Whenever a message is suspected as missing, confirmed by a missing message DTC, it is important to look for other symptoms that may also be present in the instrument cluster and throughout the vehicle. Once a DTC is set in the instrument cluster it may be helpful to review the complete message list available in Information Bus (Module Communications Network) to see what other modules also rely on the same message and run the self-test for those modules. If the message is missing from other modules, the same DTC may also be set in those modules. Confirmation of missing messages common to multiple modules may indicate that the originating module is the source of the concern or the communication network may be experiencing some problems.

The instrument cluster uses input messages from other modules to control the gauges, informational indicators, warning indicators and warning chime output over the communication networks. If a required message is missing or invalid for less than 5 seconds, the gauge or indicator that requires the message remains at the last commanded state based upon the last known good message. For example, if the door ajar status message is missing for less than 5 seconds and the door ajar indicator was on, the indicator remains in the ON state until the next good message is received. If the message remains missing or invalid for greater than 5 seconds, the instrument cluster sets a U-code diagnostic trouble code (DTC) and the output becomes a default action for the indicator or gauge. Each indicator or gauge utilizes a different default strategy depending on the nature of the indication. Refer to Instrument Cluster normal operation descriptions located before each individual pinpoint test for further description of the default action specific to each indicator or gauge. If the messaged input to the cluster returns at any time, the normal function of the gauge or indicator resumes.

Warning Chime Characteristics
Each warning chime has unique characteristics that help to identify and differentiate each warning chime. The warning chimes use volume, chime frequency, length of time the chime sounds and the number of chime tones to identify which chime is sounding. The instrument cluster prioritizes the chimes according to a preset hierarchy programmed into the instrument cluster software. When more than one chime request is received by the instrument cluster, the most important chime sounds. If a lower priority chime is currently sounding, the higher priority request takes over and replaces the lower priority chime.

There are 3 different chimes as listed below:
- Repetitive
- Single tone
- Tic-toc

The following table provides a summary of the chime characteristics including the chime priority.

Instrument Cluster Chime Characteristics/Priority (Part 1):

Instrument Cluster Chime Characteristics/Priority (Part 2):

Safety Belt Warning Chime
The safety belt warning chime warns that the safety belt is not fastened. The safety belt warning chime sounds when the driver or passenger safety belt (when a passenger is detected) is not fastened and the ignition lock cylinder is turned from the OFF/LOCK or ACC to the ON or START position.

The safety belt warning chime stops sounding when the safety belt is fastened, when the ignition switch is turned from the ON or START position to the OFF/LOCK or ACC position, or when the chime has sounded for approximately 6 seconds.

The safety belt warning chime inputs are:
- Ignition switch RUN/START status.
- Driver or passenger safety belt warning chime request communicated by the restraints control module (RCM) to the instrument cluster through the high speed controller area network (HS-CAN).

Belt-Minder(R)
The Belt-Minder(R) is configurable. To configure without using a scan tool, refer to Belt-Minder(R) Deactivating/Activating.

The Belt-Minder(R) feature supplements the current safety belt warning function and is enabled after the current safety belt warning is complete. The Belt-Minder(R) reminds the driver that the driver or passenger safety belt is unbuckled by intermittently sounding a chime and illuminating the safety belt warning lamp in the instrument cluster once the vehicle speed has exceeded 5 km/h (3 mph), and remains active for 5 minutes from the time it is started. While activated, the Belt-Minder(R) chime and indicator flash and chime simultaneously from on for 6 seconds to off for 30 seconds.

NOTE: The Belt-Minder(R) is disabled for one ignition switch ON cycle if the safety belt is buckled then unbuckled within 20 seconds during that specific cycle.

The Belt-Minder(R) warning chime inputs are the:
- Ignition switch RUN/START status
- Driver or passenger safety belt warning chime request communicated by the RCM to the instrument cluster through the high speed controller area network (HS-CAN).

Air Bag Secondary Warning Chime
The air bag secondary warning chime warns that the air bag warning indicator light does not work correctly. The instrument cluster monitors the air bag warning indicator status internally. When a fault is present in the air bag warning indicator and the instrument cluster receives an air bag warning indicator on request from the RCM, the air bag secondary warning chime sounds.

The air bag secondary warning chime inputs are:
- Ignition switch RUN/START status.
- Air bag warning indicator chime request communicated by the RCM to the instrument cluster.

Key-In-Ignition Warning Chime
The key-in-ignition warning chime warns that the key is still in the ignition lock cylinder when the driver door is ajar. The key-in-ignition warning chime sounds when the driver door is ajar, the key is in the ignition lock cylinder and in the OFF/LOCK or ACC position.

On the Hybrid, the key-in-ignition warning chime sounds 10 times with the key in RUN or START while the driver door is ajar with the transaxle in PARK (P).

The key-in-ignition warning chime stops sounding when the driver door is closed, the key is removed from the ignition lock cylinder, or if the ignition switch is turned to the ON position.

The key-in-ignition warning chime inputs are:
- Ignition switch RUN/START status.
- Key-in-ignition switch position to the smart junction box (SJB).
- Door ajar input from the driver door ajar switch to the SJB.
- Transmission park status communicated by the PCM to the instrument cluster through the high speed controller area network (HS-CAN) (Hybrid only).
- Key-in-ignition chime request communicated by the SJB to the instrument cluster through the medium speed controller area network (MS-CAN).

Headlamps On Warning Chime
The headlamps on warning chime warns that the headlamps are on when the driver door is ajar and the key is removed from the ignition lock cylinder. The headlamps on warning chime sounds if the driver door is ajar, the headlamp switch is in the PARK or HEADLAMP position, and the ignition switch is in the OFF/LOCK position with the key out.

The headlamps on warning chime stops sounding when any one of the above conditions are removed.

The headlamps on warning chime inputs are:
- Ignition switch position to the SJB.
- Key-in-ignition switch position to the SJB.
- Door ajar input from the driver door ajar switch to the SJB.
- Headlamp switch input to the SJB.
- Headlamps on chime request communicated by the SJB to the instrument cluster through the MS-CAN.

Door Ajar Warning Chime
The door ajar warning chime warns that a door is open or not fully closed. The chime sounds when any door, or the liftgate becomes ajar while the ignition switch is in the ON position.

The door ajar warning chime stops sounding and resets when all the doors and the luggage compartment lid are closed, or the ignition lock cylinder is placed in the OFF/LOCK or ACC position.

The door ajar warning lamp/chime inputs are:
- Ignition switch RUN/START status
- Door ajar data communicated by the SJB to the instrument cluster through the MS-CAN

Turn Signal On Warning Chime
The turn signal on warning chime warns that the turn signal has not been cancelled. The turn signal on warning chime sounds if the left or right turn signal is on and the vehicle has traveled more than 3.2 km (2.0 miles).

The turn signal on warning chime stops sounding if the turn signal is turned off, or if the ignition lock cylinder is turned to the OFF or ACC position.

The turn signal on warning chime inputs are:
- Ignition switch position to the instrument cluster and SJB.
- Turn signal on data communicated by the SJB to the instrument cluster through the CAN communication.
- Odometer count data communicated by the PCM to the instrument cluster through the HS-CAN.

Parking Brake Warning Chime
The parking brake warning chime warns that the parking brake is engaged when the vehicle is in motion. The parking brake warning chime sounds if the ignition switch is in ON position, the parking brake is engaged, and the vehicle speed is greater than 5 km/h (3 mph).

The parking brake warning chime stops sounding and resets if the parking brake is released, the ignition switch is not in the ON position, if the vehicle speed is less than 5 km/h (3 mph), or after 90 seconds from the time the chime is activated.

The parking brake warning chime inputs are:
- Ignition switch RUN/START status.
- Parking brake switch status communicated by the SJB to the instrument cluster through the MS-CAN.
- Vehicle speed data communicated by the PCM to the SJB through the MS-CAN.
- Parking brake warning chime request communicated by the SJB to the instrument cluster.

Turn/Hazard On Tone
Since the turn/hazard flasher is an electronic function of the SJB, the on/off sound that used to be present with standard bi-metal flashers is no longer present. To provide an audible sound and indicate that the RH/LH TURN or HAZARD indicators are on, the instrument cluster provides a tic-toc tone along with the visual turn signal indicators.

The turn/hazard on tone inputs are:
- Left turn indicator signal from the SJB to the instrument cluster through the MS-CAN.
- Right turn indicator signal from the SJB to the instrument cluster through the MS-CAN.