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What are ABS, AFU, and REF Systems?

Model: (Various brands) Various

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 replace the horn on a Renault Duster - Dacia Duster

Today's main instructions will show you the procedure for removing and replacing the horn or sound signal on the Renault Duster, as well as the Dacia Duster. First, open the bonnet of the vehicle and start removing the front bumper by unscrewing all the fixing screws; you will find the horn right in front of the radiator, as shown in the video. At this point, disconnect the electrical connector and unscrew the bracket screw to remove and replace the horn with the new one; finally, reassemble the front bumper!

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