This parking assist ECU is a direct-fit electronic control unit designed for Citroën and Peugeot models. Ideal for professional workshops and DIY mechanics, this unit (part numbers 9629825380, 659078, 601746, NFP) manages ultrasonic parking sensors and the associated warning logic to help drivers maneuver safely. Replacing a faulty parking assist ECU restores sensor processing, audible/visual alerts and CAN-bus communication related to parking aids.

Key Features And Benefits

High-value replacement for vehicles equipped with factory parking sensors. The unit interprets sensor signals, filters false triggers and issues accurate distance warnings to the driver. Compatible with original electrical connectors and mounting points to ensure secure installation and reliable operation. Commonly sought under reference numbers 9629825380 and 659078 — include these codes when searching for compatibility.

Fitment And Compatible Models

Typical applications include Citroën C5, Citroën C8 and Peugeot 807. Always verify the listed product codes against the part required for your specific vehicle generation and equipment level.

What The Unit Does

The parking assist control unit processes inputs from ultrasonic sensors, assesses obstacle distance, and sends output signals to dashboard indicators, audible buzzers, and, where fitted, visual displays. It communicates with the vehicle network (CAN) to coordinate with other driver-assistance systems and to store sensor diagnostics.

Typical Failure Modes And Causes

• Water Ingress Or Corrosion: Moisture entering connectors or the unit housing can cause intermittent faults or permanent failure.
• Physical Damage: Impact to sensors or wiring can create erroneous signals leading to ECU error states.
• Electrical Surges Or Short Circuits: Faulty wiring, after-market installations, or jump-start events may damage internal electronics.
• Connector Oxidation And Poor Contacts: Corroded pins result in communication errors between sensors and the ECU.

Replacement Procedure (General Guidance)

• Safety First: Disconnect the vehicle battery before starting to avoid short circuits and protect sensitive electronics.
• Locate Unit: Access the parking assist ECU following the vehicle manufacturer’s service manual — common locations include under the dashboard, in the trunk area, or behind trim panels.
• Disconnect Connectors: Carefully release locking tabs and remove electrical connectors. Inspect connectors and wiring for corrosion or damage.
• Remove Mounting Fasteners: Unbolt the unit and remove it from its bracket or housing.
• Install New Unit: Mount the replacement unit, reconnect all connectors securely and reassemble trim.
• Power-Up And Check: Reconnect the battery, clear stored fault codes, and perform a functional check of sensors and warnings.

Recommended Workshop Tips

• Perform A Full Sensor Check: Test each ultrasonic sensor for correct operation before condemning the ECU — a failed sensor can mimic ECU faults.
• Inspect Wiring Harness And Grounds: Repair any damaged wires or corroded grounds to prevent recurring failures.
• Fault Code Scan: Use a professional diagnostic tool to read parking assist fault codes and live sensor data during testing.
• Secure Mounting And Sealing: Ensure the unit and its connectors are properly sealed against moisture and vibration.

Technical Information

Manufacturer: Stellantis

Model: Citroën C5; Citroën C8; Peugeot 807

Product Codes: 9629825380; 659078; 601746; NFP

Other Numbers: 659078; 9629825380

Why This Part Is Frequently Replaced

Parking assist ECUs are commonly replaced when sensors report inconsistent distances, multiple sensor faults appear simultaneously, or the system ceases to provide acoustic/visual warnings. Environmental exposure (moisture, road salt), connector corrosion and prior impact damage are the most frequent root causes.

Installation Recommendation

For reliable commissioning and diagnosis use professional diagnostic equipment capable of reading parking-sensor data and clearing related fault codes. When in doubt, have the unit fitted by an experienced technician to ensure correct mounting, wiring integrity and system calibration.

Original Used Parking Assist ECU Designed For Citroën And Peugeot Models. This control unit Processes Signals From Ultrasonic Parking Sensors, Controls Audible And Visual Alerts And Interfaces With The Vehicle Electronics To Support Safe Low-Speed Maneuvering. Ideal For Professional Workshops And Skilled Do-It-Yourself Mechanics Looking To Replace A Faulty Parking Assist Module. Commonly Searched By Part Number 9629825180.

Key Features

Reliable Original-Part Replacement For Vehicles Equipped With Factory Parking Sensors. Direct Fit For Compatible Models When The Part Number Matches. Provides The Same Signal Processing And Output Functions As The Original Unit, Restoring Parking Aid Functionality When The Fault Lies In The Control Module.

Replacement And Installation Steps

• Park Vehicle On Level Ground And Switch Off Ignition.
• Disconnect Negative Battery Terminal Before Any Electrical Work.
• Locate Unit (Location Depends On Model — Often Mounted In The Rear Bumper Area, Boot Liner Or Near The Rear Lamp Cluster). Remove Interior Trim Panels To Access The Module.
• Disconnect All Electrical Connectors Carefully, Release Mounting Brackets And Remove The Faulty Unit.
• Install Replacement Unit, Reconnect Connectors And Secure Mounting Hardware. Refit Trim Panels.
• Reconnect Battery, Then Perform System Check And Sensor Test With A Diagnostic Tool. Some Vehicles Require Initialization Or Coding Of The Module To Restore Full Functionality.

Installation Recommendations

• Always Disconnect The Battery Before Removal/Installation And Follow The Vehicle Manufacturer’S Procedures To Avoid Damage To The Unit.
• Inspect Wiring Harnesses, Sensor Connectors And Fuses For Damage Or Corrosion Before Fitting The New Module.
• Protect Electrical Connectors From Moisture And Ensure Proper Sealing Of The Bumper/Boot Area After Reassembly.
• After Installation, Perform A Full Diagnostic Check And Sensor Calibration. Professional Coding/Initialization With PSA Diagnostic Equipment (DiagBox/Lexia) Is Recommended If The Vehicle Displays Fault Codes Or If The System Does Not Operate Correctly.

Most Common Reasons For Failure

• Water Ingress Or Corrosion Causing Short Circuits Or Connector Faults.
• Mechanical Damage From Rear Collision Or Impact To The Bumper Area.
• Electrical Surges, Faulty Wiring Or Poor Ground Connections.
• Degraded Internal Components Due To Age, Thermal Stress Or Long-Term Moisture Exposure.

Technical Information

• Manufacturer: Stellantis
• Model: Citroën C5; Citroën C8; Peugeot 807
• Product Codes: 9629825180
• Additional Numbers: 659078; 601746; NFP

Notes For Professionals

This Control Unit Processes Inputs From Ultrasonic Parking Sensors And Outputs Warnings To The Instrument Cluster Or Infotainment Display, As Well As Triggering Acoustic Signals. If Replacing The Module, Verify Sensor Integrity And Connector Pins To Avoid Repeating The Failure. When Fault Codes Persist After Swap, Use A Diagnostic Tool To Read Sensor Status, Perform Adaptations And Clear Historic Faults.

Why Choose This Part

Part Number Reference Increases Findability For Mechanics Searching By Code. This Unit Offers A Cost-Effective Solution To Restore Parking Assist Functionality When The Original ECU Has Failed, Provided The Part Numbers Match And Connectors Fit Correctly.

This parking assist control unit (ECU) is designed for Citroën and Peugeot vehicles and handles ultrasonic sensor input, obstacle detection logic and signal output to the vehicle’s display and audible warning systems. Ideal for professional workshops and DIY mechanics who search by OE numbers: 9629825480, 659078 or related references, this unit restores automated parking aid functions such as rear/side sensor processing and driver alerts. Compatible models commonly include Citroën C5, Citroën C8 and Peugeot 807, though fitment can vary by production year and equipment level. The unit receives sensor data via the vehicle CAN network, evaluates obstacle distance and issues appropriate visual and acoustic warnings to assist safe parking maneuvers.

Technical Information

• Manufacturer: Stellantis
• Model: Citroën C5; Citroën C8; Peugeot 807
• Product Codes: 9629825480; 659078
• Additional Numbers: 601746; NFP

Function

The parking assist ECU processes signals from ultrasonic (or other) parking sensors, monitors object proximity, calculates safe stopping distances and triggers dashboard indicators and acoustic beeps. It also communicates with other vehicle systems over the CAN bus to coordinate warnings and may disable/enable the system depending on selected gears or vehicle speed.

Typical Fault Symptoms

• Intermittent or permanent loss of parking sonar indications.
• Continuous audible alarms, false positives or constant beeping.
• Missing symbol or fault message on the instrument cluster related to parking assistance.
• Complete system inoperable despite sensors and wiring visually intact.

Why This Part Fails Most Often

Failures are commonly caused by moisture ingress, corrosion of connector pins, impact damage from minor collisions, wiring harness faults or short circuits. Environmental exposure (road salt, pressure washing) and ageing can degrade seals and electronics. Occasionally sensor faults or harness damage create symptoms that mimic ECU failure, so verify sensors and connectors before replacement.

How To Replace

Location varies by model; parking assist ECUs are often mounted in the rear luggage area, behind trim panels or under rear bumpers. Typical replacement steps:

• Disconnect the negative battery terminal before starting work.
• Remove interior trim panels or luggage compartment lining to access the unit.
• Document connector positions, then carefully unplug electrical connectors and remove mounting screws.
• Install the replacement unit, secure it, reconnect all plugs and restore trim.
• Reconnect the battery and run a system check. On some vehicles initialization or coding may be required to restore full functionality.

Installation Recommendations

Always disconnect the battery prior to removal/installation to prevent damage to electronics and follow manufacturer torque and handling guidelines. Check connectors for corrosion and repair or replace damaged sensor wiring before fitting the new ECU. After fitting, perform a full function test of all parking sensors and the parking assistance system. Where coding or adaptation is necessary, use PSA-compatible diagnostic equipment (DiagBox/Lexia/PP2000) or have the procedure performed by a qualified technician.

Expected Durability

When properly installed and protected from moisture and impact, parking assist ECUs typically last many years. Lifespan is heavily influenced by environmental exposure, the condition of connectors and any history of vehicle collisions.