The Magneti Marelli IAW 6LP2.12 Engine Control Unit (ECU) is a direct-fit engine management module designed for PSA Group vehicles equipped with the 1.4 16V KFU engine. This unit manages fuel injection, ignition timing and sensor diagnostics to ensure efficient engine operation. Commonly searched by its part numbers (9664339980, 9665936280, 16.631.064, 16.988.004, 1940XH, 1940XJ), the IAW 6LP2.12 is a frequent replacement item for technicians and DIY enthusiasts working on Citroën and Peugeot models.

Technical Information

• Manufacturer: Magneti Marelli
• Model: IAW 6LP2.12
• Product Codes: 9664339980, 9665936280
• Additional Numbers: 16.631.064, 16.988.004, 1940XH, 1940XJ

Compatibility: Fits vehicles equipped with the 1.4 16V KFU engine family for Citroën and Peugeot. This specific unit was removed from a Citroën C4 (2009). When searching, use the listed part numbers for the highest chance of matching exact variants.

Function And Common Symptoms

The ECU controls fuel delivery, ignition timing, idle control and interprets signals from sensors such as MAF, MAP, TPS, coolant temperature and crankshaft position. When the ECU malfunctions, typical symptoms include engine not starting, intermittent stalling, misfires, rough idle, reduced performance, poor fuel economy, illuminated check engine light and sometimes immobilizer or key recognition faults.

Most Common Causes Of Failure

• Moisture Ingress Or Corrosion: Water ingress or corroded connectors lead to short circuits and progressive failure.
• Thermal Stress And Aging: Repeated heat cycles or degraded solder joints can cause component failure.
• Electrical Surges Or Faulty Wiring: Voltage spikes, poor grounding or damaged wiring harnesses transmit damaging currents to the ECU.
• Mechanical Damage: Physical impacts or improper handling during removal/installation.

Installation Recommendations

• Disconnect The Negative Battery Terminal Before Starting Work To Avoid Short Circuits And Protect Vehicle Electronics.
• Observe ESD Precautions: Avoid Static Discharge By Grounding Yourself When Handling The Unit.
• Inspect Wiring And Connectors: Repair Corroded Pins, Replace Damaged Sockets And Check All Ground Points And Fuses Before Fitting The ECU.
• Fit Securely And Ensure Seals Are Intact To Prevent Moisture Ingress.
• After Installation, Program Or Pair The Unit As Required: Many ECUs Need Immobilizer Coding Or Software Configuration To Match The Vehicle—use appropriate diagnostic tools.
• Verify Operation: Clear Fault Codes, Perform A Road Test And Monitor Live Sensor Data To Confirm Proper Function.

Notes For Mechanics And DIYers: Keep the relevant part numbers handy when ordering or searching. Replacing the ECU is often straightforward mechanically, but software matching and electrical diagnosis require appropriate diagnostic equipment and experience. Address underlying causes such as wiring or sensor faults to avoid repeated failures.

This Magneti Marelli IAW 6LP2.05 engine control unit (ECU) is intended for petrol 1.4 16V KFU engines used in Citroën and Peugeot models. The unit controls fuel injection, ignition timing and related sensor inputs to ensure correct engine running, emissions and drivability. Supplied as a used replacement taken from a Citroën C4, it is a direct-fit unit for compatible vehicles when matched and prepared correctly.

Key Benefits

• Direct compatibility with 1.4 16V KFU engine installations in Citroën/Peugeot models.
• Original Magneti Marelli hardware designed for factory-level engine management.
• Commonly referenced by OEM part numbers for fast identification (see Technical Information).
• Suitable for professional workshops and experienced DIY mechanics familiar with ECU replacement and coding.

Fitment And Application

Commonly fitted to Citroën C4 and Peugeot 307 models equipped with the 1.4 16V KFU petrol engine. Check the engine type and ECU part number on the original unit before replacement. This unit is frequently searched by product codes such as 9653979480 and 9657429380.

Technical Information

• Manufacturer: Magneti Marelli
• Model: IAW 6LP2.05
• Product Codes: 9653979480, 9657429380
• Other Numbers: 16.631.054, 16.735.044, 1940XH, 1940XJ, NFP

Installation And Coding – Important

– The unit is used and is paired with the original vehicle (VIN/PIN/keys).
– Options for commissioning:
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 technician with PSA service equipment (DiagBox/Lexia/PP2000).
– Before removal/installation always disconnect the battery and follow the manufacturer’s procedure to avoid damaging the unit.

Installation Recommendations

• Always disconnect the vehicle battery before starting work and wait a few minutes to ensure all capacitors are discharged.
• Label and photograph connectors before unplugging to ensure correct reassembly.
• Remove mounting bolts and unplug harness connectors carefully; avoid pulling on wires.
• If the unit requires cloning or coding, perform the procedure with appropriate diagnostic equipment before or immediately after installation according to the chosen method (cloning or virginization).
• After installation, check for wiring harness integrity, clean connector contacts if corroded, and confirm all engine sensors operate correctly via diagnostics.

How Replacement Is Performed (Overview)

• Disconnect negative battery terminal.
• Locate the ECU (usually in engine bay or passenger footwell depending on model).
• Unplug all electrical connectors and remove securing screws or brackets.
• Install the replacement unit, secure mechanically and reconnect harnesses.
• Complete cloning or coding procedure as required (see Installation And Coding – Important).
• Reconnect battery and verify engine starts and runs; clear any fault codes and perform functional checks.

Why This Part Most Commonly Fails

ECUs like the IAW 6LP2.05 are generally durable, but failures typically result from external factors rather than normal wear. The most common causes are water ingress and moisture corrosion at connectors, thermal stress and solder joint cracks from repeated heat cycles, voltage spikes or poor battery/charging system condition, and physical damage or connector corrosion. Symptoms of a failing unit can include no-start, erratic idle, misfires, loss of fuel injection, and multiple engine management fault codes.

Notes For Buyers

Searches for this item are often performed using the OEM product codes (9653979480, 9657429380, 16.631.054, 16.735.044, 1940XH, 1940XJ). Suitable for professional installation or experienced DIY mechanics. Ensure that cloning or coding is planned as required for full functionality after replacement.

This Magneti Marelli IAW 6LP2.05 engine control unit (ECU) is a direct-fit replacement for vehicles equipped with the 1.4 16V KFU petrol engine. Designed for professional workshops and experienced DIY mechanics, the unit manages fuel injection, ignition timing and sensor signals to restore correct engine performance, drivability and emissions control. Commonly searched by part numbers and codes (IAW 6LP2.05, 9653979480, 9659099180, 16.631.054, 16.735.054, 1940XH, 1940XJ), this unit is suitable for Citroën and Peugeot platforms and is especially relevant for Citroën C4 and compatible Peugeot models with the 1.4 16V KFU engine.

Technical Information

• Manufacturer: Magneti Marelli
• Model: IAW 6LP2.05
• Product Codes: 9653979480, 9659099180
• Additional Numbers: 16.631.054, 16.735.054, 1940XH, 1940XJ, NFP
• Fits Engines: 1.4 16V KFU (Petrol)
• Typical Vehicles: Citroën C4; select Peugeot models (e.g. 307) with the 1.4 16V KFU engine

Compatibility And Application

The ECU is intended for vehicles fitted with the 1.4 16V KFU petrol engine. Fitment depends on engine code and electrical connector configuration; exact compatibility is governed by the ECU part and software version. This unit is commonly found on Citroën C4 and some Peugeot models—verify engine code on the vehicle to ensure correct replacement.

Installation

Recommended for professional mechanics or experienced DIY technicians. Basic replacement steps:

• Disconnect the negative terminal of the battery before any work.
• Locate the ECU (position varies by model: engine bay or passenger compartment). Refer to the vehicle repair manual for exact location and access procedure.
• Unplug electrical connectors carefully, release any locking tabs and note connector orientation.
• Remove mounting bolts and extract the old unit.
• Fit the replacement unit, secure mounting bolts to the manufacturer’s torque specification and reconnect all connectors.
• Perform required coding, cloning or initialization (see Installation and Coding section below) before attempting to start the engine.
• After installation, check for fault codes and verify correct engine operation and sensor readings.

Installation And Coding – Important

• The Unit Is Used And Is “Paired” With The Original Vehicle (VIN/PIN/Keys).
• Options For Commissioning:
  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 Specialist With PSA Service Equipment (DiagBox/Lexia/PP2000).
• Before Removal/Installation Always Disconnect The Battery And Follow The Manufacturer’s Procedure To Avoid Damaging The Unit.

Why This Part Commonly Fails

• Water Ingress And Corrosion Causing Connector Or Circuit Damage.
• Electrical Surges Or Poor Grounding Leading To Component Failure.
• Internal Solder Joint Cracks Due To Vibration And Thermal Cycling.
• Connector Wear Or Bent Pins Causing Intermittent Signals.
• Age-Related Electronic Component Degradation.

Symptoms Of A Faulty ECU

• Engine Won’t Start Or Cranks Without Ignition.
• Intermittent Stalling, Misfires Or Poor Running.
• Erratic Idle Or Sudden Loss Of Power.
• Persistent Engine Fault Codes Related To Sensors, Fuel Injection Or Ignition.

Replacement Advice

ECUs have no fixed service interval; lifespan depends on operating conditions. If symptoms point to ECU failure, perform a full electrical inspection (battery voltage, grounds, connector condition) and read fault codes before replacement. Where possible, cloning the original unit’s EEPROM/Flash preserves immobilizer and vehicle-specific data and is typically the fastest route to a plug-and-play result. If cloning is not available, virginization and coding with PSA diagnostic tools will be required to bring the unit into service.

Who Should Install

Suitable for professional auto-electricians and competent DIY mechanics comfortable with vehicle electronics and coding procedures. For correct commissioning of used ECUs and secure immobilizer handling, use of PSA diagnostic equipment and trained personnel is strongly recommended.

Keywords For Search

IAW 6LP2.05, Magneti Marelli ECU, Engine Control Unit, 9653979480, 9659099180, Citroën C4 ECU, Peugeot 307 ECU, 1.4 16V KFU ECU

Product Overview

High-quality engine control unit (ECU) IAW 6LP2.05 from Magneti Marelli, designed for use in vehicles equipped with the 1.4 16V KFU engine family. This unit is suitable for professional workshops and experienced DIY mechanics who need a reliable engine management module to restore proper fuel injection, ignition timing and engine operation. Commonly searched by its part numbers and codes, the ECU is a direct-fit solution for affected Citroën and Peugeot models where the IAW 6LP2.05 specification is required.

How This Unit Works And What It Controls

The ECU Controls Fuel Injection, Ignition Timing, Idle Management And Diagnostic Communication. It Receives Inputs From Sensors (Crankshaft Position, Camshaft Position, Throttle, MAP/MAF, Temperature Sensors) And Commands Injectors, Ignition Coils And Idle Actuators To Ensure Stable Engine Performance. A Faulty Unit Can Cause Misfires, Poor Starting, Increased Fuel Consumption Or Loss Of Power.

How To Replace

General Replacement Steps: Disconnect The Battery Before Any Work. Locate The ECU (Usually In The Engine Bay Or Close To The Firewall Depending On Model). Unplug Electrical Connectors Carefully And Remove Fastening Bolts. Swap The Unit, Refit Connectors And Secure Bolts With Correct Torque. After Mechanical Fitment The Unit May Require Coding Or Data Transfer To Match The Vehicle Immobiliser And Key System — See Installation And Coding Section Below.

Technical Information

• Manufacturer: Magneti Marelli
• Model: IAW 6LP2.05
• Product Codes: 9664339980, 9664934380
• Additional Numbers: 9653979480, 9650909180, 16.735.084, 16.631.064, 16.631.054, 16.735.054, 1940XH, 1940XJ
• Engine Compatibility: 1.4 16V KFU
• Origin Vehicle: Removed From Citroën C4

Installation And Coding – Important

• The Unit Is Used And Is Paired With The Original Vehicle (VIN/PIN/Keys).
• Options For Commissioning:
  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 Specialist With PSA Service Equipment (DiagBox/Lexia/PP2000).
• Always Disconnect The Battery Before Removal/Installation And Follow The Manufacturer Procedure To Avoid Damaging The Unit.

Installation Recommendations

Perform Installation In A Dry, Clean Environment. Inspect Connector Pins For Corrosion Or Bent Contacts And Clean The Mating Surfaces If Necessary. Use Proper Tools For Fasteners And Follow Manufacturer Torque Specifications Where Available. After Installation Verify Wiring Grounds And Battery Voltage. If Cloning Is Chosen, Ensure A Complete EEPROM/Flash Backup Of The Original Unit. If Virginizing, Prepare The Required Diagnostic Equipment And Original Key Information.

Most Common Failure Causes

ECUs Of This Type Typically Fail Due To Water Ingress, Corrosion On Connectors, Thermal Stress And Solder Joint Fatigue. Electrical Surges From Faulty Charging Systems Or Jump-Starting With Incorrect Polarity Can Damage Internal Electronics. Software/Immobillizer Mismatches Or Lost Key Pairings Are Also Frequent Sources Of Perceived ECU Faults.

Who Should Fit This Unit

Recommended For Experienced Mechanics And Workshops Familiar With PSA Electronics. DIY Enthusiasts With Good Electrical Knowledge Can Perform Mechanical Replacement; Coding Or Cloning Steps Should Be Carried Out By A Specialist Or With Proper Diagnostic Equipment.

Keywords For Search

ECU IAW 6LP2.05, Magneti Marelli ECU, Citroën Peugeot Engine Control Unit, 9664339980, 9664934380, 1.4 16V KFU ECU

Commonly found in models such as Citroën C4, the IAW 6LP2.05 can also replace product codes 9664339980, 9665486380, 16.735.094, 16.631.064, 1940XH, and 1940XJ, ensuring versatility in repair and maintenance.

Typically, engine control units can fail due to electrical issues, overheating, or physical damage, which may result in poor engine performance. It is essential to replace a malfunctioning ECU promptly to maintain vehicle efficiency and performance.

Technical Information:

• Manufacturer: Magneti Marelli
• Model: IAW 6LP2.05
• Product Codes: 9664339980, 9665486380
• Additional Numbers: 16.735.094, 16.631.064, 1940XH, 1940XJ