Flex Failed to Write Ford Transit 2018 SID209 ECU?

By | June 12, 2026

Problem:

It’s a Ford Transit 2018 with sid209 TC1797 ecu.
Hardware number gk4a 12a650 ua.
I’ve tried bitbox and Flex programmer. But hardware not compatible (obviously see hw not listed).
Any solution?

Flex Ford SID209 1 Flex Ford SID209 2

Solution:

Sid209 GK4A version you need to boot unlock.
Can’t write via obd straight away.

Boot for readout, never had any luck with VR’s on GK4A.
Same as Autotuner.

Do it in boot mode or use other devices.

Some had good success with Trasdata & PCM Flash.