PRE-SAFE Functions limited
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W221
PRE-SAFE Functions limited
Hello!
I drive a 2009 S550 W221 (WDDNG8GB4AA303663) and as soon as the weather has gotten colder I keep getting PRE-SAFE Functions limited See Owner's Manual on my dash. This happens every morning as soon as I touch the brake pedal and disappears when I release it (when stationary). IE when switching from P to D. Same happens while I drive the car and don't touch the pedal for a while. After three times of arriving and disappearing the error gets permanent and completely disables the pre-safe system until I restart the car. I've already checked all the SAM boxes, CAN wiring, changed that nasty battery charging level cord, checked all 4 radar sensors (2 in front and 2 in the back), switched to a new battery (both of them, actually), installed a new generator, and even changed to SGR ECU (RDU_212 A0375453432). Nothing did help me and that leaves me really frustrated since I've run out of car services in my city I haven't visited yet. The situation gets even worse while driving the freeway since even with pre-safe deactivated the system throws an error (Distronic plus inactive) when using the Distronic plus once it detects the car in front and tries to apply brakes.
I keep getting errors 726600, 550400, 530400, 520400, 560400. But all of them are "stored".
I drive a 2009 S550 W221 (WDDNG8GB4AA303663) and as soon as the weather has gotten colder I keep getting PRE-SAFE Functions limited See Owner's Manual on my dash. This happens every morning as soon as I touch the brake pedal and disappears when I release it (when stationary). IE when switching from P to D. Same happens while I drive the car and don't touch the pedal for a while. After three times of arriving and disappearing the error gets permanent and completely disables the pre-safe system until I restart the car. I've already checked all the SAM boxes, CAN wiring, changed that nasty battery charging level cord, checked all 4 radar sensors (2 in front and 2 in the back), switched to a new battery (both of them, actually), installed a new generator, and even changed to SGR ECU (RDU_212 A0375453432). Nothing did help me and that leaves me really frustrated since I've run out of car services in my city I haven't visited yet. The situation gets even worse while driving the freeway since even with pre-safe deactivated the system throws an error (Distronic plus inactive) when using the Distronic plus once it detects the car in front and tries to apply brakes.
I keep getting errors 726600, 550400, 530400, 520400, 560400. But all of them are "stored".
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W221
Well, I did clear them a dozen of times. But yet they are still there after every time the error shows up on the dash.
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2010 E550, 273 Engine: 2012 S550, 278 Engine
I don’t know what scanner you use but when you have so many failed systems it must be something simple. Wheel speed sensor is one of these simple things.
In my car even steering became stiff and CEL also was lit.
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W221
I had a similar issue. All systems went out because the front left wheel speed sensor failed. I use the iCarsoff scanner and it told me that the left front wheel speed sensor is bad.
I don’t know what scanner you use but when you have so many failed systems it must be something simple. Wheel speed sensor is one of these simple things.
In my car even steering became stiff and CEL also was lit.
I don’t know what scanner you use but when you have so many failed systems it must be something simple. Wheel speed sensor is one of these simple things.
In my car even steering became stiff and CEL also was lit.
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S500
amber is usually something isn't helping
red is a serious fault
mind you that said ABS sensors go amber - maybe it means you can keep using the car but something doesn't do what it usually does
pre safe is a, I notice you're heading towards something that's going to get in a tight situation (or worse) so I'm getting ready for the smash, when activated (on my earlier car) it snatches the seat belts tight, closes the windows, optimises the seats for a crash and puts ABS full on. So the ABS sensors are part of the issues and a common bit of fun on the w221.
red is a serious fault
mind you that said ABS sensors go amber - maybe it means you can keep using the car but something doesn't do what it usually does
pre safe is a, I notice you're heading towards something that's going to get in a tight situation (or worse) so I'm getting ready for the smash, when activated (on my earlier car) it snatches the seat belts tight, closes the windows, optimises the seats for a crash and puts ABS full on. So the ABS sensors are part of the issues and a common bit of fun on the w221.
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S500
abs sensors progressively fail on this model - have you noticed the park brake do strange things (off when u put it on, doesn't want to come off automatically ?) - I forget i don't think ABS senors left errors for the first few months
you haven't told us what kit u r diagnosing with the codes in your first post are not merc fault codes
you haven't told us what kit u r diagnosing with the codes in your first post are not merc fault codes
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W221
abs sensors progressively fail on this model - have you noticed the park brake do strange things (off when u put it on, doesn't want to come off automatically ?) - I forget i don't think ABS senors left errors for the first few months
you haven't told us what kit u r diagnosing with the codes in your first post are not merc fault codes
you haven't told us what kit u r diagnosing with the codes in your first post are not merc fault codes
I did use both Xentry and Launch. Unfortunately, I did not save Xentry error codes. The abovementioned codes are from Launch Xdiag.
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S500
ABS sensors on this model die to time - its like clockwork- yours is the exact age hitting a pre determined failure mode - so it would be a good idea to fit them regardless - who deleted the post saying this earlier ?
there was important other info on the symptoms re park brake functionality related to ABS sensor failure and pre safe bongs too
there was important other info on the symptoms re park brake functionality related to ABS sensor failure and pre safe bongs too
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W221
I have no errors saying 'ABS sensors are as good as dead' or 'incorrect signal received from that abs piece of junk' in any of ECU memory and Pre-Safe amber error occurs even when the car is in P and not moving at all, but you are saying it still could be one of those sensors?
Just double-checking before I spend another couple hundred dollars on finding the root of pre-safe evil.
Just double-checking before I spend another couple hundred dollars on finding the root of pre-safe evil.
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S500
you could try the old fronts at the back and see if the fault goes away
its only a lump of collied copper wire, its just that Mercedes invented special dissolve to time wire for this model - so I'd be quite happy to swap them anyway
its only a lump of collied copper wire, its just that Mercedes invented special dissolve to time wire for this model - so I'd be quite happy to swap them anyway
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2010 E550, 273 Engine: 2012 S550, 278 Engine
I get the malfunction of the safety features in rain and sometimes when going thru car wash. Just a few days ago when this happened in a wash I opened the hood and saw the wire connector to the front radar sensor all wet. I think this is my problem in rain and now in car wash too. I have not done anything to it yet but will install some sort of a shield in the back side of the grille to protect this connector from getting wet.
in my E550 this connector is way better protected from rain etc. I was very surprised to see this connector in “open” in my S550.
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W221
Unfortunately, that is not my case. It's not raining every day, both the radar and the car itself are clean and all the wirings and connectors were checked several times.
I'll have to try switching the ESP unit, after all, I suppose. Still, gotta try installing front/new abs sensors on the rear axel.
I'll have to try switching the ESP unit, after all, I suppose. Still, gotta try installing front/new abs sensors on the rear axel.
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not sure why - merc literature says to always replace both sensors on a given axel at the same time. I just did all 4 on mine, and when playing with the old ones struggled to get good readings - but one I think a rear, was different - both the park brake strange behaviour and the later ESP error message went straight off
