Instrument Panel Cluster (IPC) - System Operation and Component Description

MS-CAN

Refer to: Communications Network - Overview (418-00 Module Communications Network, Description and Operation). Refer to: Communications Network (418-00 Module Communications Network) .

All messaged inputs to the IPC from other networks are received from the GWM over the HS-CAN3. The GWM, as the name implies, acts as a gateway to convert messages from one of the other 3 networks to the HS-CAN3, which is recognized by the IPC.

Network messages can drop out or be missing for a variety of reasons, such as intermittent network concerns or high network traffic on the bus. The IPC incorporates a defined strategy for handling missing network messages based on time. The required time for a network message to be missing differs between the various gauges, indicators and message center displays. The strategy is basically the same for all indication outputs (gauges, indicators or chimes), but differs in the length of time required for the network message to be missing. If a required network message is missing or invalid for less than the programmed length of time, the gauge, indicator or message center display that requires the network message remains at the last commanded state based upon the last network message received. If the messaged input is missing for longer than the programmed length of time, the IPC output (gauge, indicator etc.) reacts according to a pre-defined default action.

For example, if the stability-traction control indicator request network message is missing for less than 5 seconds, and the stability-traction control indicator (sliding car icon) was on, the indicator remains in the on state until the next network message is received. If the network message remains missing or invalid for more than 5 seconds, the IPC sets a U-code DTC and the IPC output becomes a default action for the indicator or gauge. The indicator may default on/off or the gauge may default to the rest position.

Each indicator or gauge utilizes a different default strategy depending on the nature of the indication. Refer to the diagnostic overview descriptions located before each pinpoint test for further descriptions of the default action specific to each indicator or gauge. If the missing messaged input to the IPC returns at any time, the normal function of the gauge, indicator or message center display resumes.

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. which module controls the output of the feature. whether the module that receives the input controls the output of the feature, or whether it outputs a message over the communication network to another module.

Startup-Shutdown

The IPC provides a startup/shutdown sequence also known as a welcome/goodbye strategy. The IPC initiates and follows a progressive strategy providing increasing IPC functionality from IPC wake up to ready to drive status. This sequence begins at RKE unlock or driver door open through the ignition RUN state. During this period, the IPC provides increasing functionality from backlighting or illuminating gauge rings, gauge pointers, illuminating the PRNDL, backlighting of the message center display, displaying a message center splash screen, gauge and LED prove out, gauge sweep and finally normal IPC operation.

MyKey®

The MyKey® feature allows the customer to program a restricted driving mode that is tied to one or more keys known as a MyKey® key. The following features are provided by the IPC when a MyKey® key is being used:

At the beginning of vehicle start up, as part of the welcome strategy, the message center greets the MyKey® driver with MYKEY ACTIVE DRIVE SAFELY displayed in the message center. If the MyKey® speed limiter feature is turned on, the message center also displays the MyKey® administrator selected top speed setting message; SPEED LIMITED TO XXX KM/H (XX MPH). The MyKey® top speed selections are; 105, 110, 120 or 130 km/h (65, 70, 75, or 80 mph) or to the administrator desired setpoint. The IPC provides a periodic Belt-Minder® warning chime until the driver and passenger safety belts are buckled. When the Belt-Minder® is issued, the ACM is muted and the message center displays BUCKLE UP TO UNMUTE AUDIO. If the MyKey® speed limiter feature is turned on and the vehicle speed approaches the selected top speed (100, 110, 120 or 130 km/h [60, 70, 75, or 80 mph]), the message center displays NEAR VEHICLE TOP SPEED along with a chime.