ENGINE · 2019-present
M139 tuning
M139 — Mercedes-AMG A45 S / CLA45 S 2.0 turbo (most powerful 4-cyl). I4 turbo direct injection hand-built, 2.0 L, 382-421 HP (A45 S 421) stock. Cars: Mercedes-AMG A45 S W177, CLA45 S C118, GLA45 S H247, GLB35/45.
Engine specs
| Engine code | M139 |
|---|---|
| Configuration | I4 turbo direct injection hand-built |
| Displacement | 2.0 L |
| Production years | 2019-present |
| Stock power | 382-421 HP (A45 S 421) |
| ECU family | Bosch MG1CS024 → |
Tuning stages on M139
| Stage 1 | +50-80 HP |
|---|---|
| Stage 2 | +100-130 HP (downpipe + intake + intercooler) |
| Stage 3 | +150+ HP (G35/G42 turbo upgrade + E85 + fuel system) |
Conservative real-world estimates. Actual results depend on hardware health, fuel quality, ambient temperature, and the specific calibration written.
Services available on M139
Common DTC codes on M139
Brands running M139
Workshop workflow
- Read the M139 ECU via OBD or bench using your existing flasher (KESS3, AutoTuner, MPPS, Trasdata, FRF).
- Open Softechpro V5 and drag the .bin / .ori / .hex / .s19 / .frf onto the workspace. The Bosch MG1CS024 variant is auto-detected.
- Pick the service tab and apply Stage 1 / 2 / 3 / DPF OFF / EGR OFF / AdBlue OFF as required.
- Save patched .bin — the TPROT v6/v7 + HMAC-SHA1 is recomputed automatically.
- Flash via your existing flasher. Adaptation reset via OEM scan tool if required.