Is pre-safe brake system always on?
Is pre-safe brake system always on?
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From: Canada
2010 E63, Iridium Silver, Black, Dark Ash, Distronic Plus, Night Vision, Premium
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2008 R350 & 2008 C300
The Pre-Safe system is always on, but I'm not 100% sure the Pre-Safe functions for the Distronic System are on when Distronic isn't activated, which I think was the original posters question.
*Quote* (1) Should the car ahead suddenly slow down or stop, the DISTRONIC Proximity Warning System will issue audible and visual warnings. If the calculated closing speed is too high, the PRE-SAFE Brake system automatically engages up to 40% of available braking power(2) and primes the brakes to deliver full power the moment you step on the brake pedal.(3) And if the brakes have still not been applied within 0.6 seconds of calculated impact, PRE-SAFE Brake will automatically engage them at 100% strength, dramatically reducing collision energy.
So yes Pre-Safe is always on, but would appear that certain functions wouldn't work unless Distronic was active as well.
*Quote* (1) Should the car ahead suddenly slow down or stop, the DISTRONIC Proximity Warning System will issue audible and visual warnings. If the calculated closing speed is too high, the PRE-SAFE Brake system automatically engages up to 40% of available braking power(2) and primes the brakes to deliver full power the moment you step on the brake pedal.(3) And if the brakes have still not been applied within 0.6 seconds of calculated impact, PRE-SAFE Brake will automatically engage them at 100% strength, dramatically reducing collision energy.
So yes Pre-Safe is always on, but would appear that certain functions wouldn't work unless Distronic was active as well.
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The Pre-Safe system is always on, but I'm not 100% sure the Pre-Safe functions for the Distronic System are on when Distronic isn't activated, which I think was the original posters question.
*Quote* (1) Should the car ahead suddenly slow down or stop, the DISTRONIC Proximity Warning System will issue audible and visual warnings. If the calculated closing speed is too high, the PRE-SAFE Brake system automatically engages up to 40% of available braking power(2) and primes the brakes to deliver full power the moment you step on the brake pedal.(3) And if the brakes have still not been applied within 0.6 seconds of calculated impact, PRE-SAFE Brake will automatically engage them at 100% strength, dramatically reducing collision energy.
So yes Pre-Safe is always on, but would appear that certain functions wouldn't work unless Distronic was active as well.
*Quote* (1) Should the car ahead suddenly slow down or stop, the DISTRONIC Proximity Warning System will issue audible and visual warnings. If the calculated closing speed is too high, the PRE-SAFE Brake system automatically engages up to 40% of available braking power(2) and primes the brakes to deliver full power the moment you step on the brake pedal.(3) And if the brakes have still not been applied within 0.6 seconds of calculated impact, PRE-SAFE Brake will automatically engage them at 100% strength, dramatically reducing collision energy.
So yes Pre-Safe is always on, but would appear that certain functions wouldn't work unless Distronic was active as well.
All the radar based pre-safe features are active all the time irrespectively if Distronic Plus cruise control is on or off. But you can switch off the radar system from the cluster menu and of course if all radars are switched off, those pre-safe features that work on radar info will neither be functional (radars are supposed to be switched off at certain locations like close to radio astronomy stations, a car with navigation would do this automatically).
Also note that the proximity warning system with automatic braking would not help avoiding all collisions, the main intention is to reduce the severity of a chrash (although in many cases the collision can be avoided completely, and even more often if the driver reacts from the first warning).
