Circuit Description

Instrument panel cluster (IPC) performs internal tests on EEPROM each time that IPC performs a write function to a memory address in EEPROM. IPC reads back data that has been written and compares it to the data.

DTC B1656 will set if data does not match after 3 consecutive write and verify attempts, IPC will indicate a write malfunction is current.

Under all fault conditions, DTC B1656 will clear automatically when IPC no longer detects an internal write malfunction. This DTC also requires a successful write in order to change from current to history. History DTCs will clear after 50 consecutive ignition cycles. Current or history DTCs can be cleared using scan tool, or IPC clearing DTCs feature.