Description
Blaupunkt RD4 CD car radio for CITROËN and PEUGEOT vehicles. The radio must be coded to the vehicle using diagnostics.
Original Blaupunkt RD4 CD head unit designed for many PSA vehicles. This unit restores factory audio functions with a direct OEM fit, offering reliable CD playback and radio reception while maintaining the vehicle’s original dashboard appearance. Ideal for professional workshops and experienced DIYers who need a proven replacement part identified by common product numbers (9659138977 / 657932 / 6579PC).
Compatibility
- Citroën Berlingo (B9)
- Citroën C2
- Citroën C3
- Citroën C3 Picasso
- Citroën C3 Pluriel
- Citroën C4 (selected versions)
- Citroën C8 (selected versions)
- Peugeot 207
- Peugeot 307 (including Mk2)
- Peugeot 807
- Peugeot Partner Tepee
Technical Information
- Manufacturer: Blaupunkt
- Model: RD4 CD
- Product Codes: 9659138977, 657932, 6579PC
- Additional Numbers: PSA/Stellantis references commonly listed under the above codes
Installation Recommendations
Before starting any work, always disconnect the vehicle battery to prevent damage to the unit and vehicle electronics. Remove surrounding trim panels and the securing bolts to extract the original radio. Carefully unplug the antenna lead and electrical connectors; inspect connectors and wiring for corrosion or damage. Fit the replacement unit by reversing removal steps, ensuring all plugs are fully seated and the antenna is secure. Verify the correct fuse rating before reconnecting the battery.
Programming and Coding
This radio requires coding to the vehicle via diagnostic equipment to function correctly. Use PSA diagnostic tools such as DiagBox / PP2000 (or equivalent compatible diagnostic interfaces) to register and initialise the unit. Without proper coding the radio may have limited functionality or may not be recognised by the vehicle CAN network. If you are not experienced with PSA coding procedures, commissioning the programming to a technician with appropriate diagnostic equipment is recommended.
Most Common Causes Of Failure
- Worn CD mechanism or laser pickup failure after many years of use.
- Water ingress or moisture causing corrosion to internal electronics or connectors.
- Electrical issues such as poor ground, blown fuses, or voltage spikes damaging power circuits.
- Corroded or loose connectors leading to intermittent audio or power loss.
- Software/compatibility issues when installing an uncoded or incorrectly coded unit.
How To Replace
- Disconnect the negative battery terminal and wait a few minutes.
- Carefully remove trim surrounding the radio using appropriate trim tools to avoid damage.
- Unscrew the head unit mounting bolts and slide the unit out of the dash.
- Unplug the antenna cable and electrical connectors, noting connector positions.
- Fit the replacement radio, connect all leads and the antenna, then secure with mounting bolts.
- Reconnect the battery and use diagnostic equipment to code/register the radio to the vehicle.
- Perform a full function test: radio, CD playback, controls, and any integration with steering wheel or vehicle systems.
Why This Unit
The Blaupunkt RD4 CD is a factory-style replacement that preserves original vehicle aesthetics and basic audio functions. Using the correct product codes (9659138977 / 657932 / 6579PC) ensures you receive a unit compatible with PSA dashboards. Suitable for mechanics and competent DIY installers who can perform the physical swap and arrange the necessary diagnostic coding.
