Description
Control unit – automatic headlight correction unit for CITROEN C4 and C5 II cars
Part description
This Valeo light control unit is used to control the automatic headlight correction function (typically for xenon systems) in Citroën/Peugeot cars. If you are dealing with non-functioning tilting, incorrect light height or regulation failures, the correction unit is usually one of the parts that is searched for and changed.
For the correct selection, it is essential to follow the part numbers listed below – in practice, this type of electronics is most often traced by the OEM code (e.g. 9658054280 or 6224K8).
Technical information
- Manufacturer: Valeo
- Model: Citroën C4; Citroën C5 II
- Other numbers: 9658054280 00; 6224R6; 6224R5; NFP
Product codes
- Product codes: 9658054280; 6224K8; 6224R6; 6224R5; NFP
Installation recommendations
Generally/typically for electrical equipment control units, the exact procedure may vary depending on the specific car design and installation. Below is a practical and safe general procedure.
1) Before assembly
- Compare the part codes on the unit (min. 9658054280 / 6224K8) with the old part and what is listed in the diagnostics/service documentation.
- Check the condition of the connectors: bent pins, oxidation, loose latches, damaged wiring insulation.
- Visually verify that the unit is free of leaks, corrosion or mechanical damage.
2) Necessary tools and materials (in general)
- Basic set of gola/bits and screwdrivers according to the type of fastening
- Plastic pry bar for removing covers/upholstery (according to access)
- Cleaner for electrical contacts, or a soft brush
- Protective gloves, flashlight
3) Step-by-step assembly procedure
- Turn off the ignition, remove the key/card and wait for the units in the car to sleep.
- Disconnect the battery (to minimize the risk of short circuits and damage to the electronics).
- Get access to the unit (depending on the specific design of the car, it may be necessary to remove the cover/trim).
- Document the connection: take a photo of the connectors and wiring so you don’t mix anything up during assembly.
- Unlock the connectors and disconnect them carefully – do not pull on the cables, always on the body of the connector.
- Unfasten the unit and remove it.
- Compare the old and new piece (codes, type of connectors, attachment).
- Sit the unit into place and screw/fasten it firmly into the bracket.
- Connect the connectors as far as they will go and check that the latches are properly engaged.
- Perform a visual inspection of the wiring to make sure there are no pinches or pulls anywhere.
- Connect the battery and turn on the ignition.
- Verify headlight function and correction response (and possibly perform a diagnostic check if available).
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4) Post-assembly checks and test drive/function verification
- Check that there are no light dropouts/corrections and that the connectors hold without play.
- After driving for a short time, check again for spontaneous disconnection of connectors or errors caused by poor contact.
5) The most common assembly mistakes + how to avoid them
- Disconnecting/connecting live connectors → always disconnect the battery first.
- Connector not clicked in → after connecting, check the latch and gently pull the connector (not the cable).
- Wrong part by number → compare all available codes (9658054280, 6224K8 and others) before assembly.
- Ignoring the oxidation in the connector → clean the contacts and let the cleaner ventilate before plugging in.
Reasons why the part is damaged
- Moisture and corrosion in the connectors or at the place of assembly (leakage, condensation).
- Surge/voltage fluctuations in the on-board network (weak battery, inappropriate starting, unstable charging).
- Bad contacts – loose pins, transition resistors and subsequent heating.
- Mechanical stress on cabling or connectors (tension, vibration, improper handling).
- Unprofessional intervention in the electrical installation (additional modifications, non-original connection without proper securing).
