Circuit Description
The Instrument Cluster (IPC) performs internal tests on the EEPROM each time that the IPC performs a write function to a memory address in the EEPROM. The IPC reads back the data that has been written and compares it to the data. If the data does not match after three consecutive write and verify attempts, the IPC will indicate a write malfunction is current.
Conditions for Setting the DTC
| • | The data read back after a write does not match the data being written three consecutive times. |
| • | The IPC detects an internal write malfunction. |
| • | The condition must occur when data is being written. |
Action Taken When the DTC Sets
| • | Stores a DTC B1656 in the IPC memory. |
| • | No driver warning message will be displayed for this DTC. |
| • | The IPC will store the value being written in another memory address in the EEPROM. |
Conditions for Clearing the DTC
| • | This DTC requires a successful write in order to change from current to history. |
| • | The IPC no longer detects an internal write malfunction. |
| • | A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present. |
| • | Use the On-Boards clearing DTCs feature. |
| • | Use a scan tool. |
Diagnostic Aids
Since the EEPROM cannot be removed from the IPC and DTC B1656 is an internal IPC malfunction, the IPC may need to be replaced. Refer to diagnostic table.
Test Description
The numbers below refer to the step numbers on the diagnostic table:
-
Perform the Instrument Cluster (IPC) Diagnostic System Check before continuing with the diagnosis of this DTC.
-
Clear all DTCs and cycle ignition to check that the DTC did not falsely set.
-
Clear all DTCs after the repair procedure is complete.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Was the Instrument Cluster Diagnostic System Check performed? | -- | |||
Is the DTC still present? | -- | System OK | ||
3 | Replace the Instrument Cluster (IPC). Refer to Instrument Cluster Replacement . Is the module replacement complete? | -- | -- | |
Are all DTCs cleared? | -- | -- |
