High-quality Blaupunkt RD4 CD OEM radio unit designed for a range of Citroën and Peugeot models. This unit is commonly fitted as original equipment and appears under multiple PSA part numbers, making it a frequent replacement for workshops and DIY enthusiasts. It supports CD playback, AM/FM radio and integrates with vehicle systems when properly programmed. Ideal for mechanics and home mechanics looking for a direct-fit replacement with genuine OEM cross-references.

Key Features

• OEM Blaupunkt RD4 CD unit used by Citroën/Peugeot.
• Supports CD playback and standard radio functions (AM/FM).
• Direct-fit replacement for multiple PSA models — plug-in electrical connectors and mounting points.
• Requires diagnostic coding/programming to restore full functionality and disable theft protection.
• Commonly searched by OE numbers (useful for fast lookup in parts systems).

Technical Information

• Manufacturer: Blaupunkt (OEM for Citroën/Peugeot)
• Model: Citroën C2, Citroën C3 (I), Citroën C4, Citroën C8, Peugeot 207, Peugeot 307 (II), Peugeot 807
• Product Codes: 9659138977, 9647521077, 9660646877
• Other Numbers: 657932, 6579PC

Compatibility And Fitment Notes

Fits a range of PSA vehicles where the RD4 CD radio was originally installed. Always check the physical connector layout and bracket positions when replacing to ensure plug-and-play installation. This radio is frequently listed under the OE numbers above and under model groups for Citroën and Peugeot compact and mid-size cars.

Installation Recommendations

– Before starting work, disconnect the vehicle battery to avoid short circuits and protect vehicle electronics.
– Remove trim panels and use the correct radio removal keys or tools to extract the unit without damaging the dash.
– Unplug all connectors carefully, note antenna and auxiliary leads, and transfer any OEM brackets or trim pieces to the replacement unit if necessary.
– Install in reverse order and ensure connectors seat fully. Reconnect the battery only after physical installation is complete.
– The radio must be coded/initialized with a PSA-compatible diagnostic tool (DiagBox/PP2000/Lexia) to unlock anti-theft protection and restore full functionality (steering wheel controls, presets, etc.).

Most Common Failure Reasons

• Anti-theft lock or coding mismatch after replacement — unit appears dead or limited until properly programmed.
• CD mechanism wear or mechanical failure from frequent use or foreign objects in the tray.
• Connector corrosion or poor grounding causing intermittent power or audio issues (common in older vehicles or after water ingress).
• Failed internal components such as display/backlight or power supply capacitors due to age and thermal stress.
• Blown fuse in the vehicle wiring or damaged antenna connection can mimic radio failure.

Practical Tips For Workshops

• Keep diagnostic equipment ready — many of these units require coding to clear theft lock and restore presets.
• Check fuses and connector pins before condemning the radio; many faults are simple to diagnose at the harness level.
• When supplying a used or exchanged unit, verify the part numbers match the vehicle’s original references to minimize programming issues.
• Label removed screws and trim pieces during disassembly to speed up reassembly and avoid dash rattles.

Keywords

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