GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The instrument cluster performs an internal self - test when the ignition switch is turned on in order to determine the integrity of the instrument cluster.

Conditions for Running the DTC

The ignition switch is turned from OFF to ON.

Conditions for Setting the DTC

The DTC sets under any of the following conditions:

    • The internal supply voltage is out of range for more than 10 seconds.
    • An EEPROM checksum error exists.

Action Taken When the DTC Sets

The SERVICE VEHICLE SOON indicator illuminates.

Conditions for Clearing the DTC

    • A current DTC B1000 will clear when the malfunction is no longer present and the ignition switch is cycled.
    • A history DTC will clear if the condition for this DTC is no longer present after 100 ignition cycles.

Diagnostic Aids

Since DTC B1000 is an internal instrument cluster malfunction, replace the instrument cluster.

Step

Action

Yes

No

1

Did you perform the Instrument Cluster Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Replace the instrument cluster. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

System OK

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