PeterUbers

Hi

14 e63

Did a search and wanted to know if anyone has experienced this: does it absolutely mean an error code was thrown and/or there is a problem with a sensor?

My car and windshield are perfectly clean and after getting this error first thing on startup this morning it went away 30 minutes into the drive on its own

All parktronic and windshield sensors are clean and unobstructed

Thanks in advance

Had an "....unavailable" message for a bunch of items on my 14 e550 and they had to replace a bunch of harnesses under warranty as per a tsb

SLpat

I have gotten that same message going through a drive through car wash or in periods of heavy rain. I assumed it was due to the distronic and blind spot system and the water.

In all cases I have had after the water stops it resets in a few minutes.

I have not seen it in start up.

Sean1234

I had this issue once after my battery died and I jump started the car. I did a factory reset with the on board computer in the dash and it has never happened again. Other than in the winter when I get snow and ice on the sensors that is

rediesel

I had it happen in winter a lot with frost/snow/ice buildup. Think heavy rain may have made it quit once. I imagine it could happen this time of year if you pull a car out of a cool garage on a humid day.

Funny thing is I get that big yellow warning every time I turn ESP off in my C63 - which is most of the time. Figure that's how you drive that E63 anyway.

PeterUbers

Good info, thanks guys

HDTVDinner

We have a 4 month old 2014 E350 Cabriolet and have been struggling to find answers. The car has been back to the dealer three (3) times for this issue and each time they say they solve it but never tell us how. This same warning came on again two days and the dealer says drop the car off yet again for service. We think next visit is to drop it off permanently we are so frustrated and dissapointed wit the answers this far. If you have any ideas on how to actually address the issue correctly please let us know.

PeterUbers

Mine hasn't come back

The only thing I can think of is that just the day before I personally hand washed the car in the driveway and I wonder if some moisture accumulated on any sensor that may have triggered this warning

Live Oak

It will . . .

I've been reading about this anomaly for four years now, on 2011 - 2014 cars. I've had it dozens of times. On a recent 3,000 mile trip in the west, four incidents, in varying environments, sometimes nobody else around, no bugs, no cops --- simply no possible explanation.

Give up on the dealer --- nobody knows what's going on. Probably some inscrutable software bug they just don't have the resources to find and stamp out.

rediesel

If it still isn't working a trip to the dealer is probably in order. I wouldn't give them any reason to pin the fault on you (ie I washed the car). If it's not working as properly they should fix it.

bw000327

Having read about this problem, it looks like that MB has not been able to fix this for quite a few years. I have a 2014 GL550, the "pre-saft function currently limited" sign came up shortly after I bought the car. I have taken the car to the dealer at least three time in the past few months. Each time I was told a different reason, e.g., software problem, loose connection, etc. and each time I was told that the problem was fixed and should not come back again. However, it does come back! I am rather frustrated that MB does not have a fix for this and it is unbelievable that MB is not capable of finding a solution!

rich-96db

Every few weeks I was getting an error message that pre-safe was non-operative, which resulted in the car losing it's ability to accelerate. It was a lot of fun when that happened on the highway. The dealer said they took off the front bumper and repositioned the sensor unit. There have been no error codes since then.

Royce118

This happened on mine recently as well. Car is only 7 months old and I have been getting this message along with the Collision Prevention Plus Inoperative. Dropped my car in to the dealer and was told that the car needs software updates. Will update once I get the car back and report if the problem has been solved.

unr1

software update doesn't really make sense. If that were the case any vehicle with the "old" software should be affected

But what do I know...

Royce118

That's what I have in mind as well but like I said, I'll report back in once I get the car back.

Mr Bean

on my W212 the message pops up on the dash and then the car goes into limp mode. stuck in 2 gear. awfully strange.

CaliBenzDriver

The PreSafe error is a message that gives drivers uneasy feelings about their car when it shows up.

Now with LimpMode, the car itself decides to react conservatively to a powertrain error. This can lead to down right dangerous outcomes on the open roads when surrounded by moving traffic.

These two overzealous errors are associated with computers glitching over low voltage. Fortunately these faults are usually temporary and not about fried electronics.

There are couple things you can do to skirt problems associated with low voltage... your pick:

• Get a pair of fresh batteries
• Float your main battery as often as convenient
• Scan your OBD2 port for diagnostic faults
• Reboot your computers with battery resets
• Drive with Headlights ON to peg 13.5Volts Min
• Display battery vitals while driving
• Visit Benz specialist regularly...

PreSafe sensors and Powertrain modules are directly controlled by the main ECU computer.
I am researching causes and cures for this sweet chaos. ​​​​​​Join the fun!
>

nc211

On mine, I get the Pre-safe error message ever so often, but I know what it is and have been told it's usually the same culprit - the driver's seatbelt latch. Something in there wears out and starts to short out or gets so dirty that the current for the sensor drops. I know it plugs into the control unit under the seat. I know it's that, because if I jam some electrode spray cleaner into it, it goes away for about a week. Then it dries out, and comes back on, and on, and on, and on. and. on. I have a new seatbelt latch, cost like $90 or so from the dealership, just haven't had the time to change it out yet. Not a hard thing to do.

Try a can of electronics cleaner from Autozonelandwhatever. Spray it in the seatbelt latch and see if it goes away.

Potrice

Very informative post thank you! I'm having the same issue in my 2013 ML350 BT. Everything works (sensor wise) but when I get inside my suv, the belt doesn't tighten anymore and I get the pre-safe functions bla bla bla. My front collision assist also stopped working (I guess the car doesn't want to turn it on since it thinks my seat belt isn't working properly). I might call the dealership and order a new seatbelt latch just to try and see if it fixes the problem.

jacrab

Hi all just joined I've drove mercedes cars for 25 years now,I hope this message will help anyone with the dreaded message pre safe function limited I was advised by a friend of a friend who works for mercedes to take car for a long journey I drove around 75 miles message was still there until next morning message gone that's been 2weeks now and it has not returned but still crossing my fingers every time I start car.so hope this helps others