Description
Blaupunkt RD4 CD car radio for Citroën and Peugeot vehicles. The radio must be coded to the vehicle using diagnostic equipment.
Overview
Direct-fit OEM radio unit commonly used in Stellantis vehicles (Citroën and Peugeot). This Blaupunkt RD4 CD unit is a reliable replacement for workshop repairs and DIY installations alike. It restores the factory radio functions while keeping the original dashboard appearance and connector layout. The unit is often searched by its product codes, so listing these references increases the chance of a quick match during part lookup.
Technical Information
- Manufacturer: Blaupunkt
- Model: RD4 CD
- Product Codes: 9659138977, 657932, 6579PC
- Other Numbers: Stellantis / OEM fitment references for Citroën and Peugeot
- Compatible Models: Citroën Berlingo B9, Citroën C2, Citroën C3, Citroën C3 Picasso, Citroën C3 Pluriel, Citroën C4, Citroën C8, Peugeot 207, Peugeot 307 (including 307 II), Peugeot 807, Peugeot Partner Tepee
How To Replace
Suitable for experienced mechanics and competent DIY enthusiasts. Typical replacement steps:
- Disconnect the negative battery terminal before starting work.
- Remove the trim surrounding the radio using appropriate plastic trim tools to avoid damage.
- Unscrew the radio mounting screws and carefully slide the unit out of the dash.
- Disconnect the wiring harnesses: power/ground, amplifier/aux connectors (if present) and the antenna cable.
- Fit the replacement unit, reconnect connectors and antenna, and secure the radio back in the mounting frame.
- Reconnect the battery and power up the unit.
- Code/pair the radio to the vehicle using manufacturer-level diagnostic equipment (DiagBox/Lexia or equivalent) so the unit permits full functionality.
- Verify radio operation, sound output, and any integrated steering wheel controls or vehicle bus functions.
Mounting Recommendations
Always follow safe workshop practice: disconnect the battery to prevent short circuits and protect vehicle electronics. Use the correct trim removal tools to avoid cosmetic damage. Ensure all connectors and the antenna are fully seated; poor connections are a common source of intermittent faults. Check related fuses and the vehicle ground if the unit does not power up. After installation perform a diagnostics session to complete coding and to confirm there are no stored faults on the vehicle bus.
Why The Part Commonly Fails
Common causes of radio failure include worn or seized CD mechanisms, connector corrosion or poor electrical contact, blown fuses or damaged wiring, and loss of proper coding following battery replacement or unit swap. Physical damage from impact or water ingress can also render the unit inoperative. In many cases the hardware is functional but requires proper diagnostic coding to restore full operation.
