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.

Engine control units (ECUs) play a vital role in the vehicle’s fuel injection system, ensuring optimal fuel efficiency and emission control. They continuously monitor various engine parameters and adjust functions accordingly to maintain performance.

It’s important to replace the ECU when experiencing performance issues, as they may deteriorate over time due to heat and vibrations, leading to faulty readings and engine malfunctions. Regular checks can help identify when a replacement is necessary.

Technical Information

• Manufacturer: MAGNETI MARELLI
• Model: IAW 6LP2.05
• Product Codes: 9664339980, 9664164680
• Additional Numbers: 16.735.074, 16.631.064, 1940XH, 1940XJ

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

As a critical part of the engine management system, the control unit regulates fuel injection and optimizes engine performance, ensuring efficient operation and reduced emissions. With its advanced technology, it plays a vital role in vehicle functionality, affecting acceleration, fuel efficiency, and overall driving experience.

When considering a replacement, it’s important to be aware that control units like the IAW 6LP2.12 may fail due to electrical issues, moisture ingress, or manufacturing defects. Regular inspections of your vehicle’s electronic components can prevent unexpected failures.

Technical Information:

• Manufacturer: Magneti Marelli
• Model: IAW 6LP2.12
• Product Codes: 9665936280, 9664339980
• Other Numbers: 16.631.064, 1607022280, 1607022380