GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Park Avenue 🢒 Body and Accessories 🢒 Instrument Panel, Gauges, and Console 🢒 Instrument Cluster Description

The instrument cluster serves as the primary interface between the driver and the vehicle. The instrument cluster includes the following components:

    • Gauges
    • Driver Information Center (DIC)
    • Indicators
    • Odometers

In addition, the instrument cluster communicates with other major electronic components over a class 2 serial data line.

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

    • Speedometer
    • Engine RPM (Tachometer)
    • PRNDL
    • English/Metric Display
    • Fuel Level
    • Odometer Display
    • Driver Information Center (DIC) Display (W/UB7) including Warning/Status Messages
    • Head Up Display (HUD) Interface (W/UA6)
    • Warning/Status Indicators
       - Antilock
       - AIR BAG
       - BRAKE
       - High Beam
       - SECURITY
       - SERVICE ENGINE SOON
       - SERVICE VEHICLE SOON
       - Turn Signals
       - Fasten Safety Belt

The instrument cluster has the capability to diagnose malfunctions in the following components:

    • The instrument cluster sensors
    • The input switches
    • The instrument cluster components
    • The instrument cluster systems

When the instrument cluster or another microprocessor-controlled module detects a malfunction, one of the following actions may occur in order to alert the driver:

    • An instrument cluster indicator turns on.
    • The driver information center (DIC) displays a message.

Some indicator lamps and the instrument cluster messages have dual controls.

Base and Uplevel (UB7) Instrument Clusters

Both types of instrument clusters are discussed in this description, followed by parameters specific to the base and uplevel instrument cluster. The base and uplevel instrument clusters are not interchangeable. Replace an instrument cluster only with an instrument cluster of the same type.

Instrument Cluster Functions

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

    • Recognizes operational malfunctions
    • Alerts the driver through indicators or DIC messages
    • Stores DTCs which identify malfunctions for the technician

In order to perform all of these functions, the instrument cluster microprocessor has the following items:

    • Inputs
    • Outputs
    • Program software

Instrument Cluster Keep Alive Memory (KAM)

The instrument cluster contains a data storage area. The data storage area saves data when the ignition switch is turned off. The data is lost when the battery power is removed. The data storage area is called Keep Alive Memory (KAM). The instrument cluster uses the Keep Alive Memory (KAM) in order to store the following information:

    • Trip odometer information
    • Fuel data information
    • DTC information

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

Instrument Cluster EEPROM

The instrument cluster contains a data storage area. The data storage area saves data even when battery power is removed. The data storage area is referred to as the Electrically Erasable Programmable Read Only Memory (EEPROM). The instrument cluster uses the EEPROM in order to store the following information:

    • Odometer information
    • Option information
    • Manufacturing information

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