Mechanical Instrument Cluster

Instrument cluster includes a speedometer, tachometer, fuel gauge, engine coolant temperature gauge, Vacuum Fluorescent (VF) display and a series of warning lights. Powertrain Control Module (PCM) sends signals necessary for cluster to position gauges. Cluster receives these messages over PCI bus and translates them into gauge positions. Body Control Module (BCM) sends status of all indicator lights and dimming level to instrument cluster over PCI bus when ignition switch is in RUN or START positions.

Malfunction (CHECK ENGINE) indicator light status is sent to BCM from PCM over PCI bus. VF display works when ignition switch is in RUN or START positions. BCM stores mileage information that VF displays for odometer reading. If PCI bus is not functioning, VF display will display dashes instead of mileage numbers. BCM sends mileage message and dimming level message to VF display when ignition switch is in ON position. All other instrument cluster features only work when ignition switch is in RUN position.