Circuit Description
DTC B1556 is an internal Body Control Module (BCM) fault.
Conditions for Setting the DTC
The BCM performs a data check on every EEPROM write. The BCM sets this fault if the data does not match after three consecutive attempts.
Action Taken When the DTC Sets
Stores a DTC B1556 in the BCM memory.
Conditions for Clearing the DTC
| • | The conditions for the fault are no longer present. |
| • | A history DTC will clear after 50 consecutive ignition cycles if the condition for the fault is no longer present. |
Diagnostic Aids
| • | The DTC may be set as a history DTC with no affect on the control module. |
| • | If the DTC is retrieved as both a history DTC and a current DTC, the module must be replaced. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Body Control System Schematics | |||
1 | Perform the Diagnostic System Check for the system exhibiting symptoms. Did you perform the Diagnostic System Check for the system exhibiting symptoms? | Go to Step 2 | Go to Diagnostic System Check for the system exhibiting symptoms |
2 | Does the scan tool indicate that the DTC is current? | Go to Step 3 | Go to Diagnostic Aids |
3 |
Important: Perform the set up procedure for the BCM. Replace the BCM. Refer to Body Control Module Replacement . Did you complete the replacement? | System OK | -- |
