Ford SID206 and SID803A: Focus, C-Max, Mondeo and Transit TDCi ECU Files Explained

Ford’s TDCi diesels of the 2004–2012 era use Siemens/Continental engine ECUs: the SID803A on the 1.6 TDCi (Fiesta, Fusion, Focus II, C-Max, Volvo C30/S40/V50 1.6 D) and the SID206 on the 1.8 and 2.0 TDCi (Focus II, C-Max, Mondeo III/IV, S-Max, Galaxy, Transit Connect and Transit 2.2). Both are frequent subjects of no-start diagnosis, and both have full support in our catalogue for original, virgin and immo off files.

PATS: how the Ford immobilizer behaves

Ford’s PATS stores key data in the instrument cluster (or the PCM on some Transits). A used SID ECU carries the PATS code of the donor car, so the engine cranks but does not fire and the PATS lamp flashes in a fault pattern. Fault codes B1600 / B1601 / P1260 (theft detected) point straight at the pairing.

Which file solves which problem

• Virgin file — resets the PATS block so the ECU can be paired to your car with IDS/FORScan (“PATS parameter reset”, 10-minute timed procedure). Correct choice for a replacement ECU on a road car.
• Immo off — bypasses PATS in the ECU. For engine swaps, cluster failures and vehicles where the timed procedure keeps failing.
• Original file — restores a unit that was bricked or mis-tuned; does not change PATS. Also the basis for DPF and EGR solutions on the 2.0 TDCi.

Reading the SID206 and SID803A

1. OBD: KESS V2, MPPS and Galletto read both units in most software versions; the SID206 has a large flash (1–2 MB) and the read takes several minutes.
2. Bench: KTAG and Flex read the SID206 and SID803A via the bench connector, which is needed when the ECU is locked or no longer communicates. The SID803A also has an external 95160 EEPROM that some tools read separately.
3. Record the Ford part number (5M51-12A650-xx, 7M51-12A650-xx etc.) and the Siemens number 5WS40xxx; the last letters of the Ford number identify the software version and decide which file fits.

After writing

With a virgin file, run the PATS reset and leave the ignition on for the full timer. With immo off, the engine starts at once; the PATS lamp may keep flashing but the car drives normally. If it still does not start, check the crank sensor and fuel priming on the 1.6 TDCi — air in the low-pressure system produces the same symptom.

Files by ECU and brand

Browse SID206 files and SID803A files, or start from the Ford and Volvo brand pages. The related SID807EVO covers the later 1.6 TDCi Euro 5. Not listed? Send your read via the file request form.