Pre safe functions limited- car is OFF
I went into the garage today to look at something, and saw the display on showing "PRE SAFE functions limited see operator's manual"
My keys weren't on me. I didn't open or touch the car. It was just sitting there on.
I have to go for an oil change pretty soon, will have to see what dealer says, I have certified warranty on this new-ish to me used car but I hadn't seen any threads here about this issue with the car off-- just when driving, etc.
Oh, and I do not have lane assist or those options-- so I don't really have much of a Pre Safe system anyhow do I?




Was the display showing 'presafe limited' when you eventually opened the door or had it gone away?
For the past few months it does sometimes start hard after sitting a few days. Slow initial crank then fires right up. Was going to have them check at next scheduled service.
After i saw the display on I went and got my keys and started the car to see if it would be dead and I'm a bonehead and I don't remember if it went out when I opened the door or not.
since you said dealer replaced it recently. you may have gotten a bad battery.
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I wonder if it could be the second battery that is backup for the transmission that's going south and that's triggering it. I believe this car has a second battery if I remember right what I've read here.
I'll get them to check everything out. They checked charging system when they put the new battery in because I was seeing low voltages while it was running but obviously checking again seems to be in order. I was watching via an OBD-II scanner that links to my phone.
They said charging system tested fine. Left it parked 2 nights and it started strong... they tested the battery and it's good.
Of course I got it home Wednesday mid day, and Friday afternoon it started hard.
Tech noted I have several aftermarket electrical devices. Always makes me wonder if they just assume.... but I have checked myself by unplugging them all and I still got the drain after a few days.
After 3 days of not being driven it needs a jump. That's rare but it's happened 2 x
Anybody have any ideas?
Last edited by pmkalby; Mar 4, 2017 at 06:36 PM.
No codes when I ran it with star, even while the problem was active. I had to drive to a meeting due to no time to check further and it made it the full 15 miles. I disconnected the battery and have let it sit a few hours. I'm going back to the shop after work and will try and troubleshoot it further.
Hoping you found the culprit. I did replace the battery not long ago and don't believe that is the issue but will have it tested again regardless.
Last edited by Abrown3mtg; Apr 26, 2017 at 05:49 PM.
Do you have the message only, or the battery drain, too?
Well, maybe he's not aware of the meaning of that phrase....
It was the Valentine 1 Savvy module. Savvy is a module that plugs into the car's OBD-II port and supplies data and power to the V1 detector. The old versions have a known compatability issue with Mercedes, and when I unplugged the detector, the Savvy was still in the OBD-II port and that kept waking up the car's computer so my test of accessories was flawed.
I got a new module from Valentine 1 and the new programming does not wake my car up. It's been fine for months now.
I assume the dealer didn't see the drain issue because they unplugged the Savvy to run their scans....
V1 tech support confirmed the issue, the Savvy old version programming didn't realize the car was stopped, and kept asking the computer how fast the car is going, even when the car was off. The car's computer was waking up every time it was asked for data, and that kills the battery pretty quickly.
Here's a link to V1's list of problems, and again, the new programming is fine, it's if you have an old Savvy module. Call V1 tech support for details, have your Savvy serial # and they can help. They offered me a free upgrade of the Savvy programming, but I was buying a new detector for my bike already and bought a package with new Savvy and solved issue that way (sold the old one to somebody who's car isn't on the list)
http://www.valentine1.com/savvy/savvy_problem_cars.asp





