Description
CD Radio RD4 D2 N2, has two antenna inputs. The radio must be coded to the vehicle using a diagnostic tool. It is from Peugeot 407.
Overview
Replacement RD4 D2 N2 radio with CD player, designed for PSA vehicles. This unit features two antenna inputs for improved reception and is commonly found in Peugeot 407 models. Ideal for professional workshops and experienced DIYers who need a direct-fit, functionally complete head unit for vehicles equipped with the RD4 system. Product codes and reference numbers listed below help you locate the exact match quickly.
Technical Information
- Manufacturer: Stellantis / Citroën / Peugeot
- Model: RD4 D2 N2 (from Peugeot 407)
- Product Codes: 9646871777, 7643141392
- Other Numbers: 6564W5, 6564W6, 16085109YW
Compatibility
Commonly fitted to Peugeot 407 vehicles and found in some other PSA models that use the RD4 family of head units (for example certain Citroën C5 II installations). Use the product codes above to verify physical and electrical fitment.
Installation Recommendations
- Always disconnect the vehicle battery before starting removal or installation to avoid electrical damage and short circuits.
- Remove trim panels and mounting screws carefully to access the radio cage. Keep fasteners and clips organized for reassembly.
- Disconnect all harnesses and note connections: power/speaker harness, antenna leads (this unit has two antenna inputs), and any auxiliary/phone connectors.
- Fit the replacement unit, reconnect harnesses and antennas securely; loose antenna connectors are a common cause of reception problems.
- The unit must be coded/programmed to the vehicle using a diagnostic tool. For PSA vehicles, coding with manufacturer-level tools (DiagBox/Lexia/PP2000) is recommended to restore full functionality and security settings.
- After coding, test radio reception, CD operation, steering-wheel controls (if present) and any linked systems before reassembling the dash.
Why The Part Commonly Fails
- Mechanical wear in the CD mechanism — repeated use and dust ingress can cause read errors or refusal to load/eject discs.
- Corrosion or poor contact at electrical and antenna connectors, often due to moisture or long-term vibration.
- Internal electronic aging — electrolytic capacitors and solder joints can degrade over many years, leading to intermittent failures or complete loss of function.
- Power supply issues or blown fuses caused by vehicle electrical faults or improper jump-starting.
- Physical damage from impact or improper removal/installation.
Practical Tips
- Use the product and other reference numbers when searching or ordering to ensure correct unit version and connectors.
- If radio reception is weak after installation, confirm both antenna connectors are fully seated and check antenna cable continuity.
- When possible, perform the programming step with the vehicle on a stable power supply or with battery charger connected to prevent voltage drops during coding.
