Description
Overview
This BEHR Heater Servo Motor (H1959 U b 14) is an HVAC actuator designed for select PSA models, including Citroën C4 and Peugeot 307 II. Identified by codes such as EAD512 and 6447RZ, this servo motor controls blend/air distribution flaps inside the heater box, restoring precise temperature mixing and airflow direction.
Function And Symptoms Of Failure
The heater servo motor operates the internal HVAC flaps that route warm or cool air to the cabin. Common symptoms when the actuator fails include:
- Incorrect cabin temperature or inability to switch between hot and cold air
- Airflow stuck in one position (defogger, face, or feet only)
- Clicking or grinding noises from the dash area when changing vent modes
- Intermittent operation or complete loss of flap movement
Causes And Expected Service Life
Failures are most often caused by worn plastic gears, stripped splines, moisture ingress or electrical connector issues. Service life varies with use and environment but typical failures occur after many years of operation, particularly in high-mileage vehicles or those exposed to humidity and temperature cycling.
Replacement And Installation Notes
Replacement is a straightforward job for a trained mechanic or experienced DIYer. Typical steps include:
- Disconnect the negative battery terminal before starting electrical work.
- Access the actuator—usually located on or near the heater box under the dashboard or behind the glovebox on Citroën C4 and Peugeot 307 II models.
- Remove retaining screws, unplug the electrical connector and extract the faulty servo.
- Fit the new BEHR unit in the correct orientation, secure fasteners and reconnect the wiring.
- After installation, cycle ignition and HVAC controls to allow the unit to self-calibrate if required by the vehicle.
Always follow vehicle-specific repair guides for dash removal and airbag safety precautions. If electrical faults persist, check related fuses and wiring harness connectors for corrosion or damage.
Why Choose This Part
This direct-fit BEHR heater servo motor matches common OEM codes and is suited for professional workshops and DIY repairs. Using a correct-code replacement ensures proper fitment, restores full HVAC functionality and reduces repeated labor.
Technical Information
- Manufacturer: BEHR
- Model: Heater Servo Motor / HVAC Actuator
- Product Codes: H1959 U b 14, EAD512
- Additional Numbers: 6447RZ, 6447RF
- Fitment: Citroën C4; Peugeot 307 II
If you are unsure about fitment, compare part codes or consult your vehicle repair manual. Using the correct product code helps ensure a trouble-free replacement and reliable heater/blower control.
