Description
Fuel Injection Control Unit Continental SIEMENS SID 803A. It Is From A 2007 Citroën C8 2.0 HDi RHK.
This Siemens/Continental ECU (SID803A) is a direct-fit injection control unit commonly used on PSA HDi 2.0 engines. It carries original part numbers frequently searched by mechanics and DIYers, making it easy to find when diagnosing engine management faults. The unit controls fuel injection timing, quantity and interfaces with vehicle sensors and actuators to ensure proper running, fuel economy and emissions compliance.
Technical Information
- Manufacturer: Continental / Siemens VDO
- Model: Citroën C8 2.0 HDi (RHK) – 2007; Compatible With Peugeot 807 2.0 HDi Applications
- Product Codes: SID803A, 5WS40611B-T
- Other Numbers: 9661642180, 9664610980, 1942JF
Function And Typical Symptoms
The ECU Is Responsible For Controlling Injection Timing, Injector Pulse Width, Turbo/Boost Management Interfaces And Communicating With ABS/Immobilizer And Instrument Cluster. When The Unit Malfunctions, The Engine Control Strategy Can Be Lost Or Compromised.
- Engine Does Not Start Or Cranks Without Firing
- Intermittent Stalling, Rough Idle Or Misfires
- Persistent Engine Management Warning Light (MIL) Or Fault Codes Related To Injection Or Communication Errors
- Poor Fuel Economy Or Loss Of Power
Replacement And Installation
Replacing The ECU Requires Careful Handling And Some Diagnostic Steps To Restore Full Functionality:
- Disconnect The Negative Battery Terminal Before Starting To Avoid Damage From Short Circuits.
- Locate The ECU (Position Can Vary By Model; Common Locations Include Engine Bay Or Behind The Passenger Dash/Glovebox Area).
- Remove Protective Covers And Unplug All Wiring Connectors Carefully—Do Not Pull On Wires.
- Unscrew Mounting Bolts, Replace Unit And Refit Fasteners To The Correct Torque.
- Reconnect Battery, Clear Stored Fault Codes With A Diagnostic Tool And Verify Engine Starts And Runs Correctly.
- Note: On PSA Vehicles, Immobilizer Pairing/Coding Or ECU Configuration May Be Required Using A Suitable Diagnostic Interface To Match The Unit With The Vehicle’s Security System.
Installation Recommendations
- Work In A Dry, Clean Environment To Prevent Contamination; Avoid Moisture Exposure During Installation.
- Use Proper Torque Settings For Mounting Bolts And Ensure Connectors Are Fully Seated And Locked.
- Perform A Full System Scan After Installation To Clear Historical Codes And Confirm No New Faults Remain.
- If Immobilizer Or Coding Is Needed, Use Manufacturer-Compatible Diagnostic Equipment Or A Specialist Workshop To Avoid Immobilization Issues.
Why This Part Fails Most Often
Common Failure Causes Include Environmental Damage (Water Ingress, Corrosion), Thermal Stress And Age-Related Component Degradation. Voltage Spikes Or Poor Battery/Charging System Condition Can Also Damage Internal Electronics Or Lead To Intermittent Faults. Solder Joint Failures And Cracked Printed Circuit Boards Are Known Modes Of Failure In ECU Families Of This Era.
Fitment Examples
- Citroën C8 2.0 HDi (Engine Code RHK) – 2007 Example Fitment
- Peugeot 807 2.0 HDi – Selected Variants With SID803A ECU
By Matching The Unit’s Part Numbers (SID803A, 5WS40611B-T, 9661642180, 9664610980, 1942JF) You Can Quickly Identify Compatibility During Diagnosis Or Parts Sourcing. This ECU Is Suited For Professional Garages And Experienced DIYers Who Understand The Need For Correct Handling, Electrical Precautions And Potential Coding Steps After Replacement.
