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What are ABS, AFU, and REF Systems?

Model: (Various brands) Various

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The ABS, AFU, and REF safety systems are typical of Renault models: let’s look at their functions in detail; ABS is the Anti-lock Braking System: it uses sensors to measure the rotation speed of the wheels, and as soon as it detects a tendency for one or more wheels to lock, it reduces the brake fluid pressure to the affected brake caliper(s) by activating specific solenoids, only to restore it instantly when their rotation speed returns to normal.

The AFU system is the Electronic Brake Assist: its purpose is to minimise the vehicle's stopping distance by interpreting the pedal operation speed during emergency braking, correcting the driver’s action on the brake pedal and instantly providing maximum braking power.

Finally, the REF system is the Electronic Brakeforce Distribution: during driving, the load on each tyre depends on the trajectory the car is taking at that moment, its overall weight, weather conditions, etc. Therefore, in the event of braking, without an appropriate regulation system, some wheels would lock before others, causing loss of control of the vehicle.

Its task is to distribute the braking intensity differentially between the front and rear axles.


Updated on 5 March 2026 by ScegliAuto


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How to Remove the Rear Seat of a Hyundai Tucson?

To remove the rear seat of a Hyundai Tucson, follow these steps. Start by moving the front seats to their most forward position to gain space. Next, locate the release lever on the underside of the rear seat, near the floor. Press this lever down while pulling the seat upwards to unlock it from the anchor pins. Once unlocked, tilt the seat upwards and forwards to remove it from its position. Repeat this process for both sides of the rear seat. Be careful of any electrical cables or components that may be connected to the seat during removal. Once the rear seat is removed, the disassembly is complete.

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by ScegliAuto

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