Renault ECU H0M7700746044 / S101263101D Siemens Fenix Engine Control Unit

🔧 Part Overview

OEM Codes: H0M 7700746044 and S101263101D (often seen together), also cross‑referenced with 7700744412.
Component Type: Engine Control Unit (ECU) – Siemens/Bendix “Fenix” series that integrates engine management, immobilizer, and transponder reader.

🚗 Compatibility

This ECU is found in a range of Renault models from the late 1980s to mid‑2000s, across petrol and diesel variants—when fitted with the Siemens/Bendix Fenix system:

Renault 19 Phase I (B/C53) – ~1988–1992, petrol (1.7 L), also diesel versions.
Renault 21 Berlina (B/L48) – ~1985–1994, petrol engines such as 1.7 L F3N or similar, with Siemens S101263101E labeling.
Renault Megane II (2002–2005) – some listings show this ECU used in 1.9 L diesel (F9Q) Megane II.

These ECUs are reusable across models, provided the immobilizer/transponder, housing connector and software version match.

✅ Key Features & Notes

Immobilizer & Transponder: Includes pin‑code reader and transponder interface; swapping ECUs requires pairing/coding to the car’s keys.
Common Failures: Age‑related faults include power issues, ECU failure, immobilizer faults. These ECUs are often sold used or reconditioned at low cost (approx. €10–€65).
Pinouts: Variation exists (e.g., S101263101D/E/C), ensure correct engine and body-style variant before purchasing.

📋 Summary Table

OEM Codes	Description	Fits Renault Models
H0M 7700746044 / S101263101D	Siemens/Bendix Fenix ECU	• Renault 19 (1988–1992) petrol/diesel<br>• Renault 21 (1985–1994) petrol<br>• Megane II (2002–2005) diesel

🛠️ Recommendations Before You Buy

Verify compatibility using your VIN, engine code, and immobilizer system details.
If swapping ECUs, be prepared to program immobilizer PIN code and key transponder.
For replacements: prefer tested or virgin ECUs; used ones may require reprogramming/resetting.

Key features

Immobilizer & Transponder : Includes pin‑code reader and transponder interface; swapping ECUs requires pairing/coding to the car’s keys.
Common Failures : Age‑related faults include power issues, ECU failure, immobilizer faults. These ECUs are often sold used or reconditioned at low cost (approx. €10–€65).
Pinouts : Variation exists (e.g., S101263101D/E/C), ensure correct engine and body-style variant before purchasing.

🚗 Compatibility

This ECU is found in a range of Renault models from the late 1980s to mid‑2000s, across petrol and diesel variants—when fitted with the Siemens/Bendix Fenix system:

Renault 19 Phase I (B/C53) – ~1988–1992, petrol (1.7 L), also diesel versions.
Renault 21 Berlina (B/L48) – ~1985–1994, petrol engines such as 1.7 L F3N or similar, with Siemens S101263101E labeling.
Renault Megane II (2002–2005) – some listings show this ECU used in 1.9 L diesel (F9Q) Megane II.

These ECUs are reusable across models, provided the immobilizer/transponder, housing connector and software version match.

Shipping, returns and warranty

Worldwide shipping with tracking
30-day returns on unused, uninstalled parts
90-day limited warranty against defects

Send us your VIN and we confirm fitment before shipping. See our shipping policy and return policy.

H0M7700746044

Renault ECU H0M7700746044 S101263101D Siemens Fenix Engine Control Unit