A0225452832 / 0261204531 Mercedes W140 S-Class Engine Control Unit ECU.

Product Description

The Engine Control Unit (ECU) part number A0225452832, commonly paired with internal Bosch reference 0261204531, is a genuine OEM electronic module for certain Mercedes-Benz W140 S-Class models (especially in the 1990s era). The module manages core engine functions such as fuel injection, ignition timing, sensor feedback, diagnostics (OBD), and engine mapping.

This unit is most often available in used / tested OEM condition. Due to the sensitivity of ECUs, it’s crucial to verify part numbers, hardware & software revisions, and compatibility with your vehicle before purchase. A replacement ECU may need programming, calibration, or adaptation (immobilizer / key coding, etc.) to function properly in your car.

One listing advertises a W140 S-Class ECU with exactly A0225452832 / 0261204531 for sale.
Another listing for a W140 motorsteuergerät (ECU) includes the same number A0225452832 / 0225452832 for a 3.2 engine version.

Compatibility Table / Notes

Vehicle Model	Engine / Variant	Approx Years	ECU Part Number(s)	Notes / Conditions
Mercedes-Benz	S-Class (W140)	Mid-1990s (~1991–1998)	A0225452832 / 0261204531	Used in S-Class W140 models with engines that match ECU specs
Mercedes-Benz	Other models sharing engine architecture	—	A0225452832 variants	Potential cross-application if wiring, engine, sensors match

Important Notes & Recommendations

Even if the unit’s part number matches, differences in revision, firmware, calibration, or market variant can prevent proper operation.
Many ECUs have security / immobilizer / VIN-coded data; a replacement often needs programming or cloning to your car’s identity.
Check the label on the original and replacement ECU for hardware (HW) and software (SW) version numbers.
Ask for photos of the connector end, pin layout, and overall condition (no water damage, burnt pins, corrosion).
Ensure the seller offers a return policy or test guarantee in case the ECU doesn’t function after installation.

Compatibility Table / Notes

Vehicle Model	Engine / Variant	Approx Years	ECU Part Number(s)	Notes / Conditions
Mercedes-Benz	S-Class (W140)	Mid-1990s (~1991–1998)	A0225452832 / 0261204531	Used in S-Class W140 models with engines that match ECU specs
Mercedes-Benz	Other models sharing engine architecture	—	A0225452832 variants	Potential cross-application if wiring, engine, sensors 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.

0261204531

A0225452832 Mercedes W140 S Class Engine Control Unit ECU 0261204531 – Bosch