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 Setting the DTC
DTC B1004 indicates that the keep alive, or long term, memory in the module has been reset. It is a normal occurrence whenever power or ground is removed from the module, such as when the battery is disconnected and reconnected.
Conditions for Running the DTC
The module microprocessor must be active/awake.
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 without 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 circuit or the module ground circuit will cause the DTC to set. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
| • | If this DTC is retrieved as a Current DTC, replace the module. |
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the 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 |
Is the DTC retrieved as a current DTC? | Go to Step 3 | Go to Diagnostic Aids |
3 |
Important: Perform the programming or setup procedure for the module if required. Replace the control module setting the DTC as current. Refer to Control Module References . Did you complete the replacement? | Go to Step 4 | -- |
4 |
Does the DTC reset? | Go to Step 2 | System OK |
