Circuit Description
The BCM calibrations are stored in the EEPROM. When the ignition is first turned ON, the BCM performs internal tests on the EEPROM and can determine the integrity of its non-volatile memory. The BCM compares its previously stored checksum with the checksum calculated when the ignition is first turned ON. If the two checksums do not match, the BCM will indicate a calibration malfunction (checksum error) is current.
Conditions for Setting the DTC
| • | The stored checksum does not match the calculated checksum. |
| • | The BCM detects an internal memory malfunction (checksum error). |
| • | The condition must occur when the ignition is first turned ON. |
Action Taken When the DTC Sets
| • | Stores a DTC B0605 in the BCM memory. |
| • | No driver warning message will be displayed for this DTC. |
Conditions for Clearing the DTC
| • | This DTC requires an ignition cycle in order to change from current to history. |
| • | The BCM no longer detects an internal memory malfunction (checksum error). |
| • | A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present. |
| • | Use the IPC clearing DTCs feature. |
| • | Use a scan tool. |
Diagnostic Aids
Since the EEPROM cannot be removed from the BCM and DTC B0605 is an internal BCM malfunction, the BCM must be replaced. Refer to Body Control Module Replacement Body Control Module .
Test Description
The numbers below refer to the step numbers on the diagnostic table:
-
Perform the BCM Diagnostic System Check before attempting to diagnose a DTC B0605.
-
This repair procedure requires BCM replacement.
-
Clear all DTCs after the repair procedure is complete.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Were you sent here from the BCM Diagnostic System Check? | -- | |||
Is the replacement complete? | -- | -- | ||
Are all DTCs cleared? | -- | -- |
