Hill Assist Issues...
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'18 C63A Cabriolet
Hill Assist Issues...
I was surprised the first time I sat on a hill in my '08 C350 and the brakes of the car held the vehicle in place. Never had a car with that feature before.
Recently, I have experienced intermittent instances where the car's brakes hold it in place (you can tell the feature is activated because the pedal is rock hard and the vehicle doesn't creep when you let off the brakes) even when I'm on level ground. Anyone else? It makes take-off herky jerky and I don't like it.
Recently, I have experienced intermittent instances where the car's brakes hold it in place (you can tell the feature is activated because the pedal is rock hard and the vehicle doesn't creep when you let off the brakes) even when I'm on level ground. Anyone else? It makes take-off herky jerky and I don't like it.
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From: Toronto, ON
2011 E350 4Matic Wagon, 2013 C350 4Matic Sedan
Recently, I have experienced intermittent instances where the car's brakes hold it in place (you can tell the feature is activated because the pedal is rock hard and the vehicle doesn't creep when you let off the brakes) even when I'm on level ground. Anyone else? It makes take-off herky jerky and I don't like it.
I have experienced the hill assist on inclines upwards of 20-degrees. You know its working because you let go of the brake pedal and the car stays in place (whereas other cars would start rolling backwards).
I have never had an instance where the brake pedal has become rock hard though. The hill assist is an electronic system and doesn't affect the pedal position afaik ... unlike some cruise control systems where the gas pedal would be held down.
Perhaps something to check with the dealership?
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'18 C63A Cabriolet
Hi and welcome to the forum.
I have experienced the hill assist on inclines upwards of 20-degrees. You know its working because you let go of the brake pedal and the car stays in place (whereas other cars would start rolling backwards).
I have never had an instance where the brake pedal has become rock hard though. The hill assist is an electronic system and doesn't affect the pedal position afaik ... unlike some cruise control systems where the gas pedal would be held down.
Perhaps something to check with the dealership?
I have experienced the hill assist on inclines upwards of 20-degrees. You know its working because you let go of the brake pedal and the car stays in place (whereas other cars would start rolling backwards).
I have never had an instance where the brake pedal has become rock hard though. The hill assist is an electronic system and doesn't affect the pedal position afaik ... unlike some cruise control systems where the gas pedal would be held down.
Perhaps something to check with the dealership?
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From: Mississauga
GLA45 AMG, GLC43 AMG
I have had the rock hard feeling of the brake pedal in the past and can replicate it at will
If your on a hill and stop, and then release the brake pedal, and before the car's hill assist feature release's you hit the brake pedal again, it will become rock hard as mentioned, I don't think it's a flaw, but since the system is "under pressure" trying to push more brake fluid is not possible, and the rock hard feelings occurs....
Well I at least think this is why......
GK
If your on a hill and stop, and then release the brake pedal, and before the car's hill assist feature release's you hit the brake pedal again, it will become rock hard as mentioned, I don't think it's a flaw, but since the system is "under pressure" trying to push more brake fluid is not possible, and the rock hard feelings occurs....
Well I at least think this is why......
GK
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'18 C63A Cabriolet
I have had the rock hard feeling of the brake pedal in the past and can replicate it at will
If your on a hill and stop, and then release the brake pedal, and before the car's hill assist feature release's you hit the brake pedal again, it will become rock hard as mentioned, I don't think it's a flaw, but since the system is "under pressure" trying to push more brake fluid is not possible, and the rock hard feelings occurs....
Well I at least think this is why......
GK
If your on a hill and stop, and then release the brake pedal, and before the car's hill assist feature release's you hit the brake pedal again, it will become rock hard as mentioned, I don't think it's a flaw, but since the system is "under pressure" trying to push more brake fluid is not possible, and the rock hard feelings occurs....
Well I at least think this is why......
GK
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From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
Sounds pretty normal to me. Anything over a 5% grade will activate the system. If you let off the brake and then depress it again before the system times out and releases the brake, the pedal will feel rock hard. Anyhow, with a manual, it does make takeoff a little harder to modulate, but you will get used to it pretty quickly manual or automatic.
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Thread Starter
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'18 C63A Cabriolet
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From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
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'18 C63A Cabriolet
The problem with that is theory is that I am on the brake pedal when it happens so the brake lights should be on. My complaint is that the hill assist engages when stopped on level ground and the car has a jerky acceleration from a stop when this happens. When you lift off the brake pedal the car remains stuck and only releases a split second after you apply the gas. That split second is an abnormal one.
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From: S.Cali, US
2009 C300S 6mt
are you sure you're on level ground? if i remember reading correctly (off the driver handbook), i believe the hill assist will initiate on an uphill slope of 5 degrees or more..
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From: Mississauga
GLA45 AMG, GLC43 AMG
The problem with that is theory is that I am on the brake pedal when it happens so the brake lights should be on. My complaint is that the hill assist engages when stopped on level ground and the car has a jerky acceleration from a stop when this happens. When you lift off the brake pedal the car remains stuck and only releases a split second after you apply the gas. That split second is an abnormal one.
mine has never done this.....
very odd indeed....
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'18 C63A Cabriolet
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From: Walnut Creek, CA
325Ci, 325Cic, C300
I'm a bit late but for what it's worth, the system has worked for me very well so far. Only engages on an incline, and never holds the car back when you're already on the gas pedal. 26k miles and it's a pretty transparent system in my opinion.
My wife's BMW has this issue. It doesn't catch everytme, but when it does it is quite annoying. The only reason I haven't taken it in is because I don't really drive it that often.
Good Luck,
Paolo
My wife's BMW has this issue. It doesn't catch everytme, but when it does it is quite annoying. The only reason I haven't taken it in is because I don't really drive it that often.
Good Luck,
Paolo
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From: San Francisco, CA
2017 E300
after driving me car for a long period of time today, it occured to me that it just might be the transmission. its always been jerky in terms of down shifting especially in gear 1 and 2. Its slow to shift when you are braking almost to a stop and you accelerate again. you get that split second jerk
