High-quality Siemens engine control unit (ECU) intended for Citroën C5 2.0 HDi with RHR engine management. Commonly searched by part numbers 9655534080, 9661618180 or 5WS40264D-T, this unit is suitable for professional workshops and experienced DIY mechanics who need a reliable replacement to restore proper fuel injection and engine management functions.

Technical Information

• Manufacturer: Siemens
• Model: Citroën C5 2.0 HDi (RHR)
• Product Codes: 9655534080, 9661618180, 5WS40264D-T
• Additional Numbers: 1940YR, 1942YS, 1942X4, 1940X6, NFP

Compatibility And Fitment

Designed for use in Stellantis vehicles using the listed product codes, primarily Citroën C5 2.0 HDi (RHR). Always confirm the part number printed on the original ECU matches one of the codes above before installation. This ECU corresponds to the Siemens SID803A family used on HDi common-rail diesel engines.

Function

The ECU controls the common-rail fuel injection system and related engine functions: injector timing and duration, fuel pressure regulation, turbo boost management, EGR control signals, and processing of inputs from sensors (MAP, crankshaft position, camshaft position, temperature, etc.). Proper ECU operation is essential for correct fueling, emissions control and drivability.

Replacement Procedure

General replacement steps for experienced technicians or competent DIYers:

• Disconnect the negative battery terminal before any work to avoid short circuits or damage to electronic components.
• Locate the ECU (refer to vehicle repair manual for exact position and access procedure).
• Unplug electrical connectors carefully, release mounting fasteners and remove the old unit.
• Decide on commissioning method (see Installation And Coding section). Either clone the original module data or perform virginization and coding.
• Install the replacement unit, reconnect connectors and battery, then carry out required initialization/coding and functional checks. Clear fault codes and run the engine to verify correct operation.

Installation And Coding – Important

• The unit is used and is “paired” with the original vehicle (VIN/PIN/keys).
• Options To Commission:
  1. Cloning Data From The Old Unit (EEPROM/Flash) – After cloning the unit is plug and play.
  2. Virginization And Subsequent Initialization/Telecoding Via DiagBox (Or Online) + Key Adaptation.
• Recommended To Be Performed By A PSA Service Professional With Service Tools (DiagBox/Lexia/PP2000).
• Before Removal/Installation Always Disconnect The Battery And Follow Manufacturer Procedures To Avoid Damaging The Unit.

Installation Recommendations

• Inspect And Clean Connector Pins; Replace Damaged Seals To Prevent Moisture Ingress.
• Ensure Good Ground Connections And Secure Mounting To Minimize Vibration.
• Protect The Unit From Electrostatic Discharge When Handling; Avoid Personal Electronics Near Open Connectors.
• After Installation, Perform Full System Scan And Required Adaptations/Codings Using Appropriate Diagnostic Tools.

Common Failure Causes

• Moisture Ingress And Corrosion Of Connector Pins Or Housing.
• Electrical Surges Or Incorrect Jump-Starting Leading To Internal Component Damage.
• Thermal Stress And Vibration Causing Broken Solder Joints Or Component Fatigue.
• Physical Damage During Removal/Installation Or From Impact.
• Software Or EEPROM Corruption Which Requires Cloning Or Reprogramming.

Service Life And Notes

ECUs typically last many years, but failures may occur after prolonged exposure to harsh conditions or as a result of accidental electrical events. When replacing, match part numbers exactly and plan for cloning or professional coding to restore full functionality.

Order by the referenced product codes to ensure fast identification in search engines and parts catalogs. The listed codes (9655534080, 9661618180, 5WS40264D-T and additional numbers) are commonly used by mechanics when sourcing this ECU.

The Siemens SID 803A Engine Control Unit (ECU) is a direct-fit electronic control module commonly used on PSA 2.0 HDi diesel engines. This unit manages fuel injection timing, quantity and injector sequencing, as well as intake air management and emissions-relevant functions. Supplied with multiple OEM reference numbers, it is frequently searched by part number and is suitable for professional workshops and experienced DIY mechanics looking for a reliable replacement ECU for affected Citroën and Peugeot vehicles.

Technical Information

• Manufacturer: Siemens
• Model: Citroën C5 II 2.0 HDi (RHR)
• Product Codes: 9662273180, 9655534080
• Other Numbers: 5WS40258G-T, 1940ZE, 1940ZF, 1942X8, 1942Y0, 194003, 1942X

Function And Application

This ECU Controls Diesel Injection Parameters And Engine Management Functions. It Reads Sensors Such As Crankshaft Position, Camshaft Position, Mass Air Flow And Engine Coolant Temperature To Calculate Precise Injector Pulse Durations For Optimum Combustion, Fuel Economy And Emissions. It Is Fitted On Citroën C5 II 2.0 HDi Vehicles And Compatible PSA Models Using The RHR Engine Code.

Replacement Procedure

High-Level Steps For Replacement:

• Disconnect The Negative Battery Terminal To Avoid Short Circuits.
• Locate The ECU (Usually In The Engine Bay Or Under A Cover Inside The Cabin) And Remove Any Protective Covers.
• Unplug Electrical Connectors And Remove Mounting Bolts.
• Fit The Replacement Unit, Secure Mounting Bolts And Reconnect Connectors.
• Reattach The Battery And Perform Required Reprogramming/Immobilizer Synchronization Using PSA Diagnostic Tools (Professional Programming Is Usually Required For Correct Operation).

Installation Recommendations

• Ensure Battery Is Disconnected Before Starting Work To Protect Electronics.
• Inspect Wiring Harness And Connectors For Corrosion Or Damage; Repair Any Faults Before Installing The New ECU.
• Keep The Unit Dry And Clean During Installation; Avoid Static Discharge.
• Programming And Immobilizer Matching Should Be Performed With Compatible Diagnostic Equipment (E.g. Peugeot/Citroën Diagnostic Tools Or Professional ECU Programmers).
• After Installation, Clear Any Stored Fault Codes And Verify Sensor Readings And Engine Performance During A Road Test.

Common Failure Causes

• Water Ingress Or Moisture Causing Corrosion Of Connectors Or Internal Electronics.
• Thermal Stress And Age-Related Component Degradation Leading To Intermittent Or Complete Failure.
• Voltage Spikes, Poor Grounding Or Faulty Alternator Causing Electronic Damage.
• Connector Corrosion Or Broken Pins Resulting In Loss Of Communication Or Sensor Signals.
• Software Or Memory Corruption (Less Common) Leading To Erratic Engine Behavior.

Search By Any Of The Listed Part Numbers For Fast Identification. The Unit Is Intended For Use By Professional Technicians Or Skilled DIY Mechanics Comfortable With ECU Replacement And Reprogramming Procedures.

Are you looking for a dependable part for your Citroën C8 or Peugeot 807? Our Siemens ECU SID 803A is the perfect choice for anyone wanting quality at a reasonable price. This thoroughly tested unit ensures that your engine operates efficiently and reliably. Let your search end here with this key component for your 2.0 HDI RHR engine.

This ECU is precisely what you need to restore your vehicle’s full performance. Suitable for common repairs as well as more demanding technical interventions, this unit comes ready for direct installation with minimal additional setup required. With our product, you not only gain performance but also peace of mind, knowing you have a reliable part that has undergone careful selection and testing.

Technical Information

• Manufacturer: Siemens
• Model: Citroën C8, Peugeot 807
• Product Codes: 9655534080, 9663607880, 5WS403204E-T
• Other Numbers: 1942AZ, 1943K1

ECUs like ours play a crucial role in the modernization and efficiency of motor vehicles. The proper functioning of this unit not only means better engine performance but also optimized fuel consumption and reduced emissions. Installation is generally straightforward and can be completed in a few hours, making it ideal for mechanics and advanced DIY enthusiasts. We recommend verifying compatibility with your specific vehicle model.

By investing in our used part, you not only receive a functional and reliable product but also make a sustainable choice that supports recycling and resource conservation.

Choose wisely and ensure your car gets exactly what it needs. With our range of Siemens ECUs, you can be confident that your vehicle is in good hands.

If you own or repair Citroën or Peugeot vehicles, this ECU is an excellent choice for replacing or repairing your existing unit. It offers reliable operation and comes from a trusted source of high-quality used auto parts, providing an affordable solution without compromising performance.

When replacing this ECU, it is highly recommended to consult with a professional technician to ensure proper installation and compatibility with your vehicle’s systems. Correct installation guarantees restored engine efficiency, smooth operation, and optimized fuel consumption.

Technical Information:

Manufacturer: Siemens
Model: Peugeot 407 2.0 HDI RHR
Product Codes: 9655534080, 9661835480, 5WS40264E-T, 1940ZR, 1942YL, 1942YN, 1940ZS
Additional Numbers: The extensive list of product codes allows easy verification of compatibility with your vehicle.

This ECU is vital for accurate fuel injection control and motor management. Common ECU failures can cause engine misfires, reduced power output, or increased fuel consumption. By replacing a faulty unit with this quality part, you can effectively resolve such issues and extend the lifespan of your Peugeot 407.

Take advantage of this opportunity to equip your vehicle with a professionally sourced and cost-effective replacement ECU, ensuring full functionality and reliability. Remember that proper installation and maintenance are key to sustaining your vehicle’s optimal performance over time.

Are you looking for a reliable engine control unit for your Citroën or Peugeot? We offer a used Siemens SID 803A Engine Control Unit sourced from a Peugeot 307 II 2.0 HDI model with an automatic transmission. This specific type of unit is ideal for those who prefer quality replacement parts without the need to invest in a brand new component.

This engine control unit is a key component of your vehicle’s injection system, ensuring optimal engine performance by controlling the amount of injected fuel and the injection timing. Its proper function is essential for the efficient and economical operation of the engine. By using this unit, you gain a balance between performance and fuel consumption.

Technical Information:
Manufacturer: Siemens
Model: Peugeot 307 II 2.0 HDI
Product Codes: 5WS40421F-T, 1942T3, 1942T4, 9663607580, 9655534080, NFP

If you are an owner or a service specializing in Citroën and Peugeot vehicles, this engine control unit is the perfect choice for restoring your vehicle’s original performance. As this is a used part, we recommend that its installation be performed by a qualified technician to ensure proper functionality and performance.

If you have any questions regarding this engine control unit or its compatibility with your vehicle, do not hesitate to contact us. We are here to assist you with all your needs for Citroën and Peugeot auto parts.

This Siemens ECU is designed for the 2.0 HDi 100 kW RHR diesel engine used in Peugeot 307 models. It controls fuel injection, boost management, EGR regulation and related engine functions to ensure efficient combustion, stable idle and compliance with emissions systems. Commonly searched by OE and supplier numbers, this unit is suitable for professional workshops and experienced DIY mechanics who need a direct replacement ECU that matches the engine management requirements of the RHR 2.0 HDi powertrain.

Technical Information

• Manufacturer: Siemens
• Model: Peugeot 307 (Engine: 2.0 HDi 100 kW, Code RHR)
• Product Codes: 5WS40277G-T, 5WS40277I-T, 9655534080, 9660497480
• Additional Numbers: 1940ZA, 1940ZC, 1942T2, 1942T6

Installation Recommendations

Replace the ECU only with the ignition off and the negative battery terminal disconnected to avoid electrical damage. The ECU location can vary by model year and option level—typically it is mounted in the engine bay on the bulkhead or under the passenger footwell behind a trim panel. Basic replacement steps:

1. Park on a level surface, remove ignition key and disconnect the negative battery terminal.
2. Locate and remove any covers or trim protecting the ECU; unlock connector clips carefully and label wiring harnesses if necessary.
3. Unscrew ECU mounting bolts and withdraw the unit. Avoid touching pins and protect the unit from static discharge and moisture.
4. Install the replacement ECU in reverse order, ensuring connectors are fully engaged and fasteners torqued to manufacturer values.
5. After electrical reconnection, use a compatible diagnostic tool to initialise and program the ECU where required. Immobiliser pairing or ECU coding may be necessary for correct engine start and operation.

Most Common Failure Reasons

• Water Ingress And Corrosion: Moisture entry around connectors or housing can corrode pins and trace circuits.
• Thermal Stress And Ageing: Prolonged heat cycles degrade solder joints and electronic components, leading to intermittent faults.
• Electrical Surges Or Poor Grounding: Voltage spikes from charging systems or bad earth connections can damage internal electronics.
• Connector Wear And Mechanical Damage: Broken clips, loose terminals or impact damage cause poor contact and signal errors.
• Sensor Failures Causing Secondary ECU Issues: Failed sensors (e.g., crankshaft or camshaft position sensors) can overload diagnostics and trigger limp mode or no-start conditions.

Typical Symptoms Of A Faulty ECU Include Engine Not Starting, Intermittent Stalling, Constant Or Intermittent Check Engine Light, Reduced Engine Power (Limp Mode), Irregular Idle And Poor Fuel Economy. Lifespan Varies; Many Failures Are Related To Environmental Damage Or Electrical Problems Rather Than Normal Wear.

This ECU is primarily aimed at professional fitters and skilled DIY mechanics. Ensure correct programming and immobiliser alignment after installation to restore full engine functionality.

Vehicle owners and mechanics alike will benefit from understanding the necessity of this component, as it is prone to failure due to various factors, including electrical issues or wear from prolonged use. Symptoms of a failing ECU can include decreased performance, erratic idling, and failure to start. Regular diagnostics and timely replacement can help maintain optimal vehicle functionality.

When replacing the ECU, it is essential to ensure compatibility with your specific vehicle model. This part can be replaced easily by following the vehicle’s service manual guidelines, ensuring proper disconnection of the battery and removal of any necessary surrounding components for access.

Technical Information

• Manufacturer: Siemens
• Model: 2.0 HDI
• Product Codes: 5WS40277I-T, 9655534080, 9661835880
• Additional Numbers: 19040ZA, 1940ZC, 1942T2, 1942T6

Compatible models include:

• Peugeot 307 (2006)
• And other models featuring this ECU configuration

This product is often sought under the product numbers 5WS40313B-T, 9655534080, and 9662907080. Regular replacement of the ECU is recommended if you experience issues such as poor engine performance, check engine light activation, or irregular fuel consumption.

Installation of the ECU typically requires the following steps:

1. Disconnect the battery to ensure safety.
2. Locate the existing ECU in the vehicle.
3. Remove any connectors and fasteners holding the old ECU in place.
4. Install the new ECU by reversing the removal steps.
5. Connect the battery and perform a diagnostic check to ensure proper installation.

The function of this ECU includes monitoring various engine parameters, controlling fuel delivery, and adjusting ignition timing, making it essential for the overall functionality of your vehicle.

Technical Information

• Manufacturer: Siemens VDO
• Model: SID803A
• Product Codes: 5WS40313B-T, 9655534080, 9662907080
• Additional Numbers: 1940ZC, 1942T2, 1940NH, 1942T6, 1942T5