Description
Description
The BEHR heater servo (commonly referenced as H1959 U b 41, EAD512, 6447RZ / 6447RF) is a direct-fit HVAC actuator for PSA vehicles. It controls the temperature blend and air distribution flaps to maintain the desired cabin climate. This unit is intended for both professional automotive technicians and experienced DIY mechanics performing HVAC repairs on Citroën and Peugeot models.
Features and Function
- Direct-replacement heater servo motor for PSA vehicles; restores accurate flap movement for temperature and airflow control.
- Electrical actuator that moves blend and distribution flaps according to HVAC control inputs.
- Compact design for OEM-style fitment and straightforward installation in dashboard HVAC housings.
Fitment And Application
Compatible with Citroën C4 and Peugeot 307 II models that use PSA part references EAD512, 6447RZ or 6447RF. Always cross-check the part codes on your vehicle before ordering to confirm compatibility.
Replacement Procedure (General Guidance)
Typical replacement steps for a heater servo motor:
- Disconnect the vehicle battery to prevent electrical shorting.
- Access the HVAC unit—this commonly requires removing the glovebox or lower dashboard trim to reach the actuator mounting.
- Unplug the electrical connector and remove the retaining screws or clips securing the servo.
- Remove the faulty servo and fit the replacement in the correct orientation; reattach screws and connector.
- Reconnect the battery and cycle the ignition to allow the HVAC system to calibrate the new actuator. Confirm proper flap movement and temperature control operation.
Common Failure Modes
Heater servos typically fail due to worn internal gears, seized or degraded potentiometers, water ingress or condensation inside the HVAC box, and connector corrosion or wiring faults. Symptoms include incorrect temperature, stuck or noisy flap movement, clicking noises from the dashboard, or no response from HVAC controls.
Service Life And Maintenance
Service life varies with use and environment; many servos last for years but exposure to moisture or contaminated air can accelerate wear. Regular inspection of HVAC operation and prompt repair of leaks that allow water into the HVAC housing will extend component life.
