Part 1

Instrumentation, Message Center and Warning Chimes

Principles of Operation

NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).

NOTE: When installing a new Instrument Panel Cluster (IPC), it is necessary to upload the module configuration to the scan tool. Following installation of the IPC (Instrument Panel Cluster), download the module configuration from the scan tool into the new IPC (Instrument Panel Cluster). to carry out the Programmable Module Installation (PMI). On vehicles equipped without Intelligent Access (IA), it is also necessary to carry out a parameter reset procedure whenever a new IPC (Instrument Panel Cluster) or PCM is installed. Refer to Antitheft and Alarm Systems. Programming and Relearning

The IPC (Instrument Panel Cluster) utilizes a microprocessor to control the gauge, indicator, message center and warning chime functions. Data is sent to the IPC (Instrument Panel Cluster) over the Medium Speed Controller Area Network (MS-CAN) and the High Speed Controller Area Network (HS-CAN) bus lines and through hardwired circuitry from individual components. The IPC (Instrument Panel Cluster) uses each input to output an action to the gauges or indicators.

It is very important to understand:

- where the input originates.

- all the information necessary in order for a feature to operate.

- which module(s) receive(s) the input or command message.

- does the module which received the input control the output of the feature, or does it output a message over the communication network to another module.

- which module controls the output of the feature.

Instrument Panel Cluster (IPC)

IPC (Instrument Panel Cluster) Gateway Function

The IPC (Instrument Panel Cluster) acts as a gateway module by receiving information in one format and transmitting it to other modules using another format. For example, the IPC (Instrument Panel Cluster) receives the vehicle speed data from the PCM over the HS-CAN (High Speed Controller Area Network), converts the data into an MS-CAN (Medium Speed Controller Area Network) message and sends (gateways) the message to other network modules such as the HVAC module, the Audio Control Module (ACM) and the SJB (Smart Junction Box). This enables network communication between modules that do not communicate using the same network (HS-CAN (High Speed Controller Area Network) or the MS-CAN (Medium Speed Controller Area Network)).

IPC (Instrument Panel Cluster) Network Messages

The IPC (Instrument Panel Cluster) uses input messages from other modules to control the gauges, informational indicators and warning indicators 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 brake status message is missing for less than 5 seconds and the brake warning 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 IPC (Instrument Panel Cluster) sets a U-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 the 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.

NOTE: Whenever a network message is suspected as missing and confirmed by a missing message DTC (U-code), it is important to look for other symptoms that may also be present in the IPC (Instrument Panel Cluster) and throughout the vehicle. Once a DTC is set in the IPC (Instrument Panel Cluster), it may be helpful to review the complete message list available in Information Bus 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.

IPC (Instrument Panel Cluster) Configuration

The IPC (Instrument Panel Cluster) contains items that are configurable. While some configurable items are customer preference items, most items are configured at the end of the line production and only available for configuration through the PMI (Programmable Module Installation) procedure or by using As-Built data.

IPC (Instrument Panel Cluster) Configuration Parameters






IPC (Instrument Panel Cluster) Prove-Out

The IPC (Instrument Panel Cluster) carries out a display prove-out to verify that all module controlled warning/indicator lamps and monitored systems are functioning correctly within the IPC (Instrument Panel Cluster). When the ignition is turned to the ON mode with the engine off, the indicators illuminate to prove-out according to the following table:





Information And Message Center

The message center is an integral part of the IPC (Instrument Panel Cluster) that receives and acts upon much of the same information that is input and used to operate the IPC (Instrument Panel Cluster) gauges, informational indicators, warning indicators and warning chimes. The message center is a 2-line display located in the center of the IPC (Instrument Panel Cluster). The message center electronic functions use both hardwired circuitry and the Controller Area Network (CAN) to display information.

NOTE: This procedure is only applicable to vehicles without navigation. For vehicles with navigation, refer to Accessories and Optional Equipment.


The compass display (located in the Front Display Interface Module (FDIM)) receives battery voltage from the SJB (Smart Junction Box). The compass module (integral to the auto-dimming interior mirror) provides hardwired vehicle directional inputs to the Instrument Panel Cluster (IPC), which sends the compass information to the FDIM (Front Display Interface Module) over the Medium Speed Controller Area Network (MS-CAN). The compass is capable of self-calibrating. This decreases the need to manually set the compass. If the compass is displaying a heading (and not displaying the C or CAL indicator), the compass is in auto-calibration mode. In this mode, the compass automatically calibrates for changes in vehicle magnetics over the life of the vehicle. This auto-calibration mode makes sure the compass heading is always accurate. If the compass displays the C or CAL indicator for an extended period of time (longer than 5 seconds), this indicates the compass has been placed in the manual calibration mode and therefore, requires manual calibration.

Warning Chimes

The IPC (Instrument Panel Cluster) uses inputs that are both hardwired to individual components and messages that are sent from the other modules over the HS-CAN (High Speed Controller Area Network) or MS-CAN (Medium Speed Controller Area Network) to control the warning chime functions.

Warning Chime Characteristics

The warning chimes have unique characteristics 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 IPC (Instrument Panel Cluster) prioritizes the chimes according to a preset hierarchy programmed into the IPC (Instrument Panel Cluster) software. When more than one chime request is received by the IPC (Instrument Panel 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

- Tick-tock

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

Instrument Panel Cluster (IPC) Chime Characteristics






Active Park Assist Chime

The active park assist chime uses several different chime tones depending on the nature of the requested chime and the urgency for acknowledgement of the chime as determined by the PAM (Parking Aid Module). The chime is either 1 of 3 single tone chimes with varying tone lengths or 1 of 2 repetitive chimes with varying tone lengths and number of chime tones. Refer to Active Parking Assist or the Owner's Literature for information on the active park assist function. The message center displays instructional or fault messages combined with the active park assist chime whenever the PAM (Parking Aid Module) sends the chime on command.

The active park assist chime inputs are:

- Ignition state.

- Active park assist warning command transmitted from the PAM (Parking Aid Module) over the HS-CAN (High Speed Controller Area Network) bus.

Adaptive Cruise Control Warning Chime

The adaptive cruise control warning chime supplements the message center displays to draw the driver's attention to the need to intervene and take control of the vehicle. There are 2 levels of chime output (high priority and low priority) based upon the nature of the warning message.

The low priority adaptive cruise control warning chime is a single-tone chime that sounds to alert the driver that the adaptive cruise control system has shut itself off due to low vehicle speed (approximately 32 km/h [20 mph]) and that the driver needs to intervene if further braking is required or to resume the adaptive cruise control operation.

The high priority adaptive cruise control warning chime is also a single tone chime that is longer than the low priority chime. The chime increases in intensity and alerts the driver that the vehicle is approaching the vehicle ahead at a faster rate then the adaptive cruise control system can brake the vehicle and that the driver needs to apply the brakes to slow the vehicle down.

Both low and high priority adaptive cruise control warning chimes are accompanied by the DRIVER INTERVENE warning message.

The adaptive cruise control warning chime inputs are:

- Ignition state.

- Adaptive cruise control warning chime request communicated by the Cruise-Control Module (C-CM) to the IPC (Instrument Panel Cluster) over the HS-CAN (High Speed Controller Area Network).

Air Bag Secondary Warning Chime

The air bag secondary warning chime warns that the air bag warning indicator light does not work correctly and that a Supplemental Restraint System (SRS) fault condition exists. The IPC (Instrument Panel Cluster) monitors the air bag warning indicator status internally. When a fault is present in the air bag warning indicator and the IPC (Instrument Panel Cluster) receives an air bag warning indicator on request from the Restraints Control Module (RCM), the air bag secondary warning chime sounds.

The air bag secondary warning chime inputs are:

- Ignition state.

- Air bag warning indicator chime request communicated by the RCM (Restraints Control Module) to the IPC (Instrument Panel Cluster).

Belt-Minder(R)

The Belt-Minder(R) is configurable. To configure with a scan tool, refer to Information Bus. To configure without a scan tool, refer to Belt-Minder(R) Deactivating/Activating Testing and Inspection.

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 and simultaneously sounding a chime and illuminating the safety belt warning indicator in the IPC (Instrument Panel Cluster) once the vehicle speed has exceeded 9.7 km/h (6 mph). The Belt-Minder(R) remains active for 5 minutes from the time it is started. While activated, the Belt-Minder(R) chime provides a series of 6 chimes/safety belt warning indicator flash sequences consisting of a 1-second chime tone and safety belt warning indicator on/off state. The Belt-Minder(R) chime and the safety belt warning indicator sound and flash for 6 seconds, then the chime stops and the safety belt warning indicator remains on for 30 seconds. The IPC (Instrument Panel Cluster) repeats the chime cycle for 5 minutes.

If the vehicle speed drops below 4.8 km/h (3 mph) once the Belt-Minder(R) chime has activated, the chime turns off and the safety belt warning indicator remains on. When the vehicle speed exceeds 9.7 km/h (6 mph) again, the Belt-Minder(R) chime resumes.

The IPC (Instrument Panel Cluster) also provides a toll booth feature which allows the driver or passenger to unbuckle their safety belt after the safety belts were initially buckled. This feature provides 1 minute without warnings after the vehicle exceeds 9.7 km/h (6 mph) again with a safety belt unbuckled.

When a MyKey(TM) is in use, the driver cannot configure the Belt-Minder(R) off. Once the Belt-Minder(R) is activated, the Belt-Minder(R) continues to chime periodically and the audio system is muted until both the driver and passenger safety belts are fastened.

The Belt-Minder(R) warning chime inputs are:

- Ignition state.

- Driver or passenger safety belt warning chime request communicated by the Restraints Control Module (RCM) to the IPC (Instrument Panel Cluster) through the HS-CAN (High Speed Controller Area Network).