Description
Right rear tail light for Citroën C4 3‑door Coupé with socket and bulbs.
High-quality replacement right rear tail light designed for Citroën C4 Coupé (3‑door). This unit comes complete with bulb holders and bulbs fitted, so it is ready for direct replacement in most repairs. Ideal for professional mechanics and competent DIYers who need a reliable, OEM-style lamp assembly. Common search references include part numbers 9646801677 and 6351T6 — include these in your search to find exact matches and speed up procurement.
Technical Information
- Manufacturer: Citroën (Stellantis)
- Model: Citroën C4 I Coupé 3‑Door
- Product Codes: 9646801677, 6351T6
- Other Numbers: 9646801677 | 6351T6
Fitment / Applications
Intended for Right Rear (Passenger Side) of Citroën C4 Coupé 3‑door (first generation). Verify visual match of mounting points and connector shape before installation — the product reference numbers above are commonly used to confirm fitment.
Function And Common Failures
The rear lamp assembly provides tail, brake, and indicator lighting as well as reversing light functions where applicable. Because this unit is supplied with bulb sockets and incandescent bulbs, the most frequent faults are simple bulb burnout and socket corrosion due to moisture ingress. Other common issues include cracked lenses from impacts, damaged mounting tabs, and corroded or loose electrical connectors. In accident damage cases the entire assembly is typically replaced rather than repaired.
Replacement Procedure
General replacement steps for a standard Citroën C4 Coupé rear lamp:
- Park vehicle on level ground and switch off ignition. For safety, remove the negative battery terminal if you will be working extensively on the electrical connectors.
- Access the lamp from inside the boot/trunk by removing the trim panel covering the lamp mounting area.
- Unscrew the lamp retaining nuts or bolts (usually accessible from inside the boot) and carefully pull the lamp assembly away from the body.
- Disconnect the wiring harness by releasing the connector clip. If the unit is fitted with bulb holders, twist out the bulb holders to remove bulbs.
- Fit the new lamp: reconnect the wiring harness, insert bulb holders, align the assembly and tighten the retaining fasteners evenly. Refit the interior trim.
- Test all lamp functions (tail, brake, indicator, reversing) before returning the vehicle to service.
Installation Recommendations
- Use anti‑seize or threadlocker on fasteners as appropriate to prevent future seizure or loosening, but follow manufacturer torque specs if available.
- Check and, if necessary, clean the connector contacts and apply dielectric grease to prevent future corrosion.
- Replace bulbs with the correct type and rating specified for the vehicle. Incorrect bulbs can lead to poor light output or electrical issues.
- After installation, verify correct operation of all lighting circuits and check for any dashboard warnings related to lighting.
Why This Part Typically Fails
Failures are most commonly caused by burned‑out bulbs and moisture ingress that corrodes sockets and connectors. Impact damage from minor collisions can crack the lens or break mounting tabs. Over time, vibration and thermal cycling can degrade seals and allow water in, accelerating corrosion and electrical faults.
Notes For Professionals
Part numbers 9646801677 and 6351T6 are frequently used identifiers — include them in parts searches or repair orders to ensure correct supply. This lamp is supplied with bulb holders and bulbs, reducing installation time compared with a bare housing.
