Flashing Information

Simos 18 ECUs are generally difficult to brick during normal flashing. Most interrupted flash operations can be restarted from the beginning.

1. Normal interruptions
2. The critical cross-flash risk
3. Boot-mode recovery

Normal interruptions

A disconnect, interrupted communication or battery voltage that becomes too low does not normally brick a Simos 18 ECU.

Correct the cause of the interruption, restore a stable connection and battery voltage, and restart the flash process from the beginning.

Always use a suitable battery charger and do not disconnect the dongle or switch off the ignition during flashing.

The critical cross-flash risk

The important exception is cross-flashing a BIN from a different vehicle region.

If the immobilizer power classes do not match, a known software bug can leave the ECU locked. Normal OBD flashing cannot recover the ECU from this state.

Do not cross-flash a BIN from another region unless the immobilizer power classes are known to be compatible or the BIN has an Immo-Off patch.

Boot-mode recovery

An ECU left locked by an incompatible regional cross-flash must be recovered using boot mode. This is an advanced bench procedure and may require opening the ECU and working directly at board level.

The following open-source project documents the Simos 18 Supplier Bootloader, boot-password recovery and related low-level recovery tools:

• bri3d/Simos18_SBOOT

Important recovery address warning

Important: Do not use the Simos 18.1/18.6 erase address on Simos 18.10. Running erase_sector 80800000 on Simos 18.10 erases CBOOT. If CBOOT is erased, recovery is only possible through SBOOT.

Simos 18.1 and Simos 18.6

Use this erase command during boot-mode recovery:

erase_sector 80800000

Simos 18.10