Mechanical Instrument Cluster Description

MECHANICAL INSTRUMENT CLUSTER (MIC)
The Mechanical Instrument Cluster (MIC) is divided into 4 sections. Primary gauges (speedometer and tachometer) secondary gauges (fuel level oil pressure water temperature and charging voltage) PCI bus indicator lights and hardwired indicator lights. The gauge mechanisms are all the same the only difference is the face plate or the physical size of the gauge. The Part Time indicator left and right turn signal indicators are hard wired and are not part of any actuator or self test. The PCM sends the signals necessary for the cluster to position the gauges. The MIC receives messages directly from the bus and translates them into gauge positions indicator levels and dimming levels. These messages are received when the ignition is in the "run" or "start" position. The "check engine" indicator is sent to the BCM from the PCM over the PCI bus. The vacuum fluorescent (VF) odometer/trip display works with the key in the "run" or "start" positions. The BCM sends dimming level message to the MIC at "key ON"

On transition from "run" to "start" a bulb-check is performed. This consists of activating all PCI bus controlled indicator lamps for approximately 2 to 4 seconds.

By holding the "trip/reset" button in while turning the key to the "run" position you can actuate the MIC self test.