The instrument cluster serves as the primary interface for the vehicle' s driver.

The instrument communicates with other major electronic components over a class 2 serial data line.

The instrument cluster used in this vehicle is either a base or an uplevel (UB7). The following list is a list of instrument cluster functions:

The following list indicates the warning messages:

The instrument cluster has the capability to diagnose malfunctions in the following the cluster controls or to which the cluster communicates:

When the instrument cluster or other microprocessor-controlled module, detects a malfunction, the cluster may turn on an instrument cluster indicator or request/display a message to the driver information center (DIC). This alerts the driver that a malfunction has occurred. Some indicator lamps and instrument cluster messages have dual controls.

The base and uplevel instrument clusters are not interchangeable. Replace an instrument cluster only with an instrument cluster of the same type.

The instrument cluster contains a microprocessor which performs the following functions:

In order to perform all of these functions, the instrument cluster microprocessor has inputs, outputs, and program software.

The instrument cluster contains a data storage area that saves data when the ignition switch is turned off. The data is lost when you remove the battery power. This data storage area is referred to as keep alive memory (KAM). The instrument cluster uses this data storage area in order to store the following information:

The KAM area is an integral part of the instrument cluster microprocessor and cannot be serviced separately.

The instrument cluster contains a data storage area that saves data even when you remove the battery power. This data storage area is called electrically erasable programmable read only memory (EEPROM). The instrument cluster uses this data storage area in order to store the following information:

The EEPROM area is an integral part of the instrument cluster microprocessor, and cannot be serviced separately.

Engine coolant temperature data is sent from the PCM to the instrument cluster via the class 2 serial data line. The instrument cluster uses a look-up table in order to determine the needle deflection and a smoothing filter in order to secure a continuous response.

The instrument cluster determines the fuel by monitoring a discrete input from the fuel level sender. The raw fuel level data is filtered for gauge display purposes. The instrument cluster has 2 filter modes. A slow (heavy) filter is used whenever the vehicle is not in PARK. This prevents fuel slosh from affecting the gauge. A fast (light) filter is used whenever the vehicle is in PARK. This allows the gauge to respond quickly when the vehicle is being fueled. The instrument cluster also sends raw fuel level data to the PCM via class 2 serial data line.

The engine RPM (tachometer) gauge is driven by a discrete input from the PCM.

The PCM monitors the PNP switch in order to determine PRNDL information. This information is sent to the instrument cluster via the class 2 serial data line. The instrument cluster then displays the gear position.

The instrument cluster displays are dimmable. The indicators are non-dimmable. The instrument cluster incandescent backlighting (graphics and pointers) is directly controlled by the lighting control module (LCM) through a dimmer signal input. The instrument cluster monitors this input, and the dim enable signal input, in order to determine when to activate and the intensity of VF dimming.