Description
Mechanical heater and air conditioning control by BEHR for Citroën C4 and Peugeot 307 vehicles.
Replace a worn or malfunctioning manual climate control panel with this genuine-style BEHR mechanical HVAC controller designed for Citroën C4 and Peugeot 307 models. Ideal for professional workshops and experienced DIYers, this unit restores reliable control of temperature, fan speed and air distribution. Frequently searched under codes B5RF and 6451VK, it is a direct-fit component for vehicles with manual climate systems and offers easy installation without electronic module reprogramming.
Technical Information
- Manufacturer: BEHR
- Model: Citroën C4, Peugeot 307
- Product Codes: B5RF, 6451VK
- Additional Numbers: Stellantis references as used in Stellantis Citroën/Peugeot applications
Function and Compatibility
This mechanical control assembly manages the vehicle’s heating and air conditioning functions: blower speed, temperature regulation (blend control), air distribution (defrost, face, feet) and recirculation. It is intended for cars equipped with manual (not automatic climate control) HVAC systems. Confirm compatibility by matching the panel shape, connector type and part codes (B5RF / 6451VK) to the original unit on Citroën C4 and Peugeot 307 vehicles.
Replacement Procedure
Basic replacement steps for experienced technicians or competent DIYers:
- Remove center console trim surrounding the control panel using plastic trim tools to avoid damage.
- Unscrew fasteners securing the control unit and carefully pull the unit forward.
- Disconnect electrical connectors and any mechanical linkages (cables or levers) to the heater/vent doors—note their routing and orientation.
- Install the new unit by reconnecting connectors and linkages, secure with original fasteners and refit trim panels.
- Verify operation of all functions (fan speeds, temperature control, distribution positions and recirculation) before returning the vehicle to service.
Mounting Recommendations
- Disconnect the negative battery terminal before starting work to prevent accidental short circuits and to protect vehicle electronics.
- Use dedicated plastic trim tools to avoid trimming damage to the console and clips.
- Inspect connectors and wiring for corrosion or damaged pins; repair any faults before installing the new control.
- Ensure mechanical linkages (if present) are routed and attached exactly as on the original unit to avoid incorrect flap positions or binding.
- After installation, cycle through all positions to confirm full range of motion and proper actuator response.
Common Failure Causes
Manual climate control panels commonly fail due to wear of internal switches and potentiometers, brittle or cracked plastic knobs, and contamination from spilled liquids or dust ingress. Mechanical linkages and actuators may also wear or seize, causing loss of temperature control or inability to change air distribution. Intermittent fan speed operation is often caused by worn resistive elements or poor electrical contacts in the control unit.
Notes For Professionals
This product is aimed at professional mechanics and experienced DIY enthusiasts who can identify and replace a manual HVAC control unit. When diagnosing HVAC issues, check fuses, blower motor operation and actuator movement in addition to the control panel to avoid unnecessary replacement of perfectly good parts.
