Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Air Intake Control
The source of intake air is automatically controlled unless overridden by pressing the air recirculation switch located below the TSD. Under automatic control, the automatic temperature control (ATC) module determines the required position of the recirculation door from its 'comfort' algorithm and, if fitted, the pollution sensor.
The recirculation door is operated by an electric motor. The automatic temperature control (ATC) module provides analogue signals to the motor along a hardwired connection. A potentiometer in the motor supplies the automatic temperature control (ATC) module with a position feedback signal for closed loop control.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.