Description
Product Overview
This heater servo motor is a direct-fit BEHR unit commonly used on PSA vehicles such as the Citroën C4 and Peugeot 307 II. Identified by part numbers EAD512, H1959 U B 21 and cross-references 6447RF / 6447RZ, the actuator controls the HVAC blend/air distribution doors to maintain the selected cabin temperature. It is designed for professional workshops and competent DIYers who search by product code to find the correct replacement quickly.
Key Features
- Function: Electric heater/blend door servo motor that positions internal HVAC flaps for temperature and airflow distribution.
- Compatibility: Common fitment for Citroën C4 and Peugeot 307 II (PSA models).
- Voltage: 12V DC electrical actuator suitable for standard vehicle electrical systems.
- Search Friendly: Frequently found by part numbers EAD512, H1959 U B 21, 6447RF, 6447RZ and BEHR references.
- User Group: Targeted at mechanics and skilled DIY technicians replacing HVAC servos.
When To Replace
Replace this servo if you experience inconsistent cabin temperature, inability to change airflow direction, clicking or grinding noises from the dash area, or if the HVAC system shows erratic behaviour when changing temperature settings. Because these units are often searched by their part numbers, matching the code ensures correct fitment and avoids trial-and-error replacements.
Common Failure Modes
Typical causes of failure include worn plastic gears, motor burnout after long service life, water ingress or condensation in the HVAC box, connector corrosion, and mechanical obstructions in the flap mechanism. Failure symptoms usually appear gradually (hesitation, loss of precise positioning) or suddenly (noise, no movement).
Replacement Guide (General)
Installation steps vary by model but the general procedure is:
- Disconnect the vehicle battery to prevent electrical shorts.
- Remove lower dash panels or glovebox to access the HVAC housing (access point differs between Citroën C4 and Peugeot 307 II).
- Locate the faulty servo on the HVAC box, unplug the electrical connector and remove the securing screws or clips.
- Swap the old actuator for the new BEHR unit, secure it, reconnect the electrical plug and reassemble interior trim.
- Reconnect the battery and verify proper operation across temperature and airflow settings.
Note: Follow vehicle-specific repair manuals for precise removal steps and safety precautions. Some models require removal of additional trim or components to gain clear access to the actuator.
Technical Information
- Manufacturer: BEHR
- Model: Citroën C4; Peugeot 307 II
- Product Codes: EAD512
- Other Numbers: H1959 U B 21; 6447RF; 6447RZ
- Voltage: 12V DC
Buying Tip: Search by part codes (EAD512, H1959 U B 21, 6447RF, 6447RZ) when ordering to ensure compatibility with your specific PSA model. This servo is intended as a direct replacement for the original BEHR actuator in the listed vehicles.
If you are unsure about fitment, compare the part numbers and connector shape with your faulty unit or consult a professional technician before purchase.
