Description And Operation: Operation
The IPC has the hardware and software to simultaneously monitor multiple inputs. The microcontroller-based IPC uses these inputs to control the gauges and indicators visible on the face of the cluster, and to display the appropriate information in the electronic display unit to allow the vehicle operator to monitor the conditions of many of the vehicle components and operating systems. The IPC display provides valuable information about the various standard and optional powertrains, fuel and emissions systems, cooling systems, lighting systems, safety systems and many other convenience items. The IPC is installed in the instrument panel so that all of these monitors can be easily viewed by the vehicle operator when driving, while still allowing relative ease of access for service.
Some of the IPC inputs are hard wired, but most are in the form of electronic messages that are transmitted by other electronic modules over the Controller Area Network (CAN) data bus. The IPC microcontroller smooths the input data using algorithms to provide gauge readings that are accurate, stable and responsive to operating conditions. These algorithms are designed to provide gauge readings during normal operation that are consistent with customer expectations. However, when abnormal conditions exist such as high coolant temperature, the algorithm can provide an extreme output and the microcontroller can sound a chime through the on-board audible tone transducer to provide distinct visual and audible indications of a problem to the vehicle operator. The IPC may also produce audible warnings for other electronic modules in the vehicle based upon electronic tone request messages received over the CAN data bus. Each audible warning is intended to provide the vehicle operator with an audible alert to supplement a visual indication.
The Body Control Module (BCM) stores and compares vehicle configuration data with the IPC as well as with other Electronic Control Units (ECU) in the vehicle. This process is referred to as Programming Of Configuration of Systems Integrated (PROCSI) (also known as PROXI). If a configuration mismatch is detected, the BCM sets a DTC. A configuration mismatch DTC will require the performance of a Restore BCM PROXI Configuration routine, or a PROXI Configuration Alignment routine using a diagnostic scan tool.
The IPC circuitry operates on battery current received through a fused B(+) fuse on a non-switched fused B(+) circuit. This arrangement allows the IPC to remain functional regardless of the status of the ignition switch. The IPC circuitry is grounded through a ground circuit and take out of the instrument panel wire harness with an eyelet terminal connector that is secured by a ground screw to a ground location on the instrument panel structural support.
The hard wired circuits between components related to the IPC may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin out information and location views for the various wire harness connectors, splices and grounds.
However, conventional diagnostic methods will not prove conclusive in the diagnosis of the IPC or the electronic controls or communication between modules and other devices that provide some features of the IPC. The most reliable, efficient and accurate means to diagnose the IPC or the electronic controls and communication related to IPC operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.