GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The module contains a data storage area which can save pertinent data when the ignition is turned OFF. The Keep Alive Memory (KAM) data is lost if battery power is removed from the module. The KAM area is an integral part of the microprocessor and cannot be serviced separately.

Conditions for Running the DTC

The module microprocessor must be active/awake.

Conditions for Setting the DTC

DTC B1004 indicates that the keep alive, or long term, memory in the module has been reset. This is a normal occurrence whenever power or ground is removed from the module, such as when the battery is disconnected and reconnected.

Action Taken When the DTC Sets

The microprocessor reverts back to the base programmed critical operating data until new data is learned and stored in KAM.

Conditions for Clearing the DTC

    • A current DTC clears when the malfunction is no longer present.
    • A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Diagnostic Aids

    • This DTC may be stored as a history DTC with out affecting the operation of the module. If stored only as a history DTC and not retrieved as a current DTC, do not replace the module.
    • This DTC will never set as current during testing unless there is a non-recoverable memory failure.
    • Intermittent interruptions to either the battery positive voltage (B+) circuit or the module ground circuit will cause the DTC to set. Refer toTesting for Intermittent and Poor Connections in Wiring Systems.
    • If this DTC is retrieved as both a current and history DTC, replace the module.

Step

Action

Yes

No

Important:  Refer to Control Module References for schematics, diagnostic system checks, and repair procedures.

1

Did you perform the control module Diagnostic System Check for the system exhibiting the symptom?

Go to Step 2

Go to Control Module References for the applicable Diagnostic System Check

2

  1. Install a scan tool.
  2. Turn the ignition ON, with the engine OFF.
  3. Retrieve DTCs.

Is the DTC retrieved as a current DTC?

Go to Step 3

Go to Diagnostic Aids

3

Important: Reprogram the module if necessary.

Replace the module. Refer to Control Module References for the appropriate repair procedure.

Did you complete the replacement?

Go to Step 4

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4

  1. Use the scan tool in order to clear DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Dies the DTC reset?

Go to Step 2

System OK