When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
Please Correct Tire Pressure
My Mercedes is requesting I correct tire pressures and it has informed me that active steering assist is inoperative and active emergency stop is currently unavailable. I just wanted to go on a little road trip this afternoon to test consumption when it's 100F outside (308 wh/mi at 55 MPH in comfort mode with a/c blasting, by the way):
Door sticker says 41 psi. Only way I can correct the algorithm that someone at Mercedes wrote that triggers a pressure warning when pressures are correct is by trading my EQE in at a Porsche dealer. I also can't correct a low 12V battery when opening the hood is not permitted. And if the car needs to be towed to a dealer the do not tow message is less than helpful.
Someone need to be fired. This is just plain fookin' stoopid to the point of being ridiculous.
Your dealer or some other place probably reset the tire monitor to a pressure too high. Simply set the pressure to whatever you want and hit OK on that screen. All will be fine.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
I mean, "tow only with flatbed" or even better "load onto flatbed with wheel dollies to tow". That would be useful information. When it's 3AM and you're on the phone with AAA "do not tow" is a utterly useless message. It's a complete waste of everyone's time even displaying it. You'd have to have some sort of mental disability to think that would be a good thing to do at a time like that. Grrrr......
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
Originally Posted by bytemaster0
Your dealer or some other place probably reset the tire monitor to a pressure too high. Simply set the pressure to whatever you want and hit OK on that screen. All will be fine.
It was fine when I left home. It became not fine half way through my trip. Nobody reset anything.
EDIT: Just checked after letting it cool down and they're all at 38 psi. Anywho, I did like you said and reset the value and light went off. Feels like it's one thing after another tho...
Last edited by GreasedFolgore; Sep 9, 2023 at 07:28 PM.
I've noticed that if it's set originally at the wrong threshold, over time and with changing outdoor temps it'll eventually reach the TMPS-7 PSI pressure, triggering the warning. Once that comes on, the car shuts off all ADAS for safety reasons.
No big deal. Whoever did the PDI stored higher pressures in the system, or didn't reset it after adjusting the pressures. Cars typically ship with the tires overinflated and then during PDI the pressure gets adjusted. Whoever does the PDI is supposed to store the correct reference pressures at that point. Looks like that wasn't done. The ADAS systems disable if TPMS goes off. It's mentioned in the owner's manual, so that's also nothing to get worked up about.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
Nobody has done anything to the tires since I last went to the dealer three months ago after purchase to complain about a rattle in my passenger seat headrest. No air was added/removed and nothing was reset. The only thing I noticed was when the message initially appeared it was for just three tires and the one tire that hadn't triggered a warning yet was 119F. The others were over 120F. So looks to me like this stoopid car is trying to calculate what the pressure SHOULD be at a certain temp.
Anywho, I believe I mentioned this is my first EV but it's also my first Mercedes. To be honest, right now I'm not inclined to buy a second. I've got enough problems to deal with already. I don't need this.
Nobody has done anything to the tires since I last went to the dealer three months ago after purchase to complain about a rattle in my passenger seat headrest. No air was added/removed and nothing was reset. The only thing I noticed was when the message initially appeared it was for just three tires and the one tire that hadn't triggered a warning yet was 119F. The others were over 120F. So looks to me like this stoopid car is trying to calculate what the pressure SHOULD be at a certain temp.
Anywho, I believe I mentioned this is my first EV but it's also my first Mercedes. To be honest, right now I'm not inclined to buy a second. I've got enough problems to deal with already. I don't need this.
Tires naturally lose air. You can lose up to 1 psi per month and every 10F in ambient temperatures is 1 psi up or down as well. So depending on what they inflated it to last time you had it in, also considering that the tires may have still been warm when they adjusted it, it's not impossible for the TPMS to go off after 3 months. I always opt out of tire pressure adjustment when I take my car in for service, because they never do it right. I make sure the pressure is adjusted and stored after the tires have properly cooled down, so I know exactly what the reference pressure is.
Last edited by superswiss; Sep 10, 2023 at 04:37 PM.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
I mean, tire pressure monitoring systems have been around for what, like 20 years? This isn't new EV technology we're dealing with here. If the system is working as designed then I guess there's nothing for Mercedes to fix. I've never had this problem before with any car I've owned though and I have a feeling I'll never have this problem again after I get rid of this EQE.
@Crito , sorry you're having a rough patch. Most of us have been driving EQE with no issues at all, myself and my dad included. In my family, we've had MBs since 1988, all of which have been prime examples of reliable, durable, exceptionally-engineered and high-quality vehicle craftsmanship. I've had more problems with Hondas and Toyotas than with Mercedes-Benz vehicles. Typical? Perhaps not, but it's an anecdote. In any case, most vehicles today are largely software-defined, with the rush to market that so many manufacturers have, you'll see these issues wherever you go. Be it Tesla, Ford, VW, Mercedes, or anywhere else. I'm not sure what's happening to yours, and while I regret it, I think the car overall will be a joy rather than a liability. I can certainly understand the frustration. Best of luck wherever your automotive journey takes you.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
Yes, software engineering has become very important. As important or maybe even more than the mechanical engineering part of the vehicle. So if Mercedes believes there's nothing wrong with triggering an alert at 41 psi when the setting is 41 psi and when it's always been 41 psi then it's time for me to move on. Tesla makes great software. The mechanical part, meh, not so great but they're improving and getting better rather than denying problems and maintaining the corporate status quo.
The last screen might have been my fault actually. It's fixed now, for the time being (I might have to uninstall Intel Unison).
My volvo had the same problem with TPMS, where the dealer set pressure resulted in TPMS low pressure errors as soon as the weather got cooler and I took a long drive. I think it is hard for shops to get the default pressure right as the tires are going to be warm when they are freshly inflated.
But at least with Mercedes you have active TPMS and so the car can tell you what the actual pressure is. With Volvo you have passive TPMS (based upon tire spin) and so you get a scary low pressure warning and no idea whether you're having a sudden pressure drop or what.
I'd be happy with active TPMS. For my volvo I had to buy my own pressure gauge so that I could sanity check the errors from the car without having to hunt down a working air pump at a gas station.
So if Mercedes believes there's nothing wrong with triggering an alert at 41 psi when the setting is 41 psi
For what it's worth, my EQE tripped a tire pressure warning a few days after purchase as well. I pulled over, checked to be sure tires were okay, and reset the pressure monitoring system and it cleared. I'm guessing either dealer or factory had set it to different values. Typically, TPMS activates when the tire is lower than 7PSI below target. I'm starting to wonder if on EVs, due to load and torque requirements, it comes on with a smaller delta. In any case, it hasn't happened since then. I run my tires 2-3 PSI higher than stock - not enough to cause rounding or traction issues, but enough to counter occasional temperature swings and prevent more energy usage.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
In every other car I've owned it usually get triggered on the first cool or cold day when ambient temps drop. I've never had one trigger on a 100F summer day before unless I actually have a flat tire. And if it's no big deal then Mercedes shouldn't be disabling safety systems. That would tend to lead one to believe something that is a big deal just happened.
I'm still having issues with the infotaiment system after uninstalling Unison. Bluetooth just sort of "hiccups" or stutters every so often. I think its a hardware issue.
In every other car I've owned it usually get triggered on the first cool or cold day when ambient temps drop. I've never had one trigger on a 100F summer day before unless I actually have a flat tire. And if it's no big deal then Mercedes shouldn't be disabling safety systems. That would tend to lead one to believe something that is a big deal just happened.
I'm still having issues with the infotaiment system after uninstalling Unison. Bluetooth just sort of "hiccups" or stutters every so often. I think its a hardware issue.
I think it also alerts if the tire pressure is actually too high. That's what mine actually did - it felt that one of my tires had too much pressure. I bought the car at the end of May, but the temperatures quickly rose thereafter, hence the higher pressure. Funny, such a thing! I get why they disable ADAS though - you could easily get into a split-mu traction situation that would make the ADAS unaware of a developing traction differential. MB always plays it safe. But yes, it's very disconcerting!
Have you tried resetting the head unit? BTW, MBUX is due for a pretty nice upgrade in the next month or two. Cars will be getting Dolby Atmos as well, among other quality of life improvements.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
But it wasn't too high. It was just right, same as its ever been. The pressure is about 4 psi lower than it was three months at the ambient temp three months ago. At 100F ambient its still correct. In any case, its clear that whatever the car is trying to say is completely lost on me.
Infotainment system seems to power down completely when I lock the car. It's not just asleep. i wait until I see the leds around the usb ports go out just to make sure any capacitors drain before unlocking again. That appears to give me a "cold boot".
EDIT: To clarify, I believe it shuts down the infotainment computer when I lock the doors but it doesn't power down completely until the USB ports go dead (lights go off).
Last edited by GreasedFolgore; Sep 12, 2023 at 08:14 PM.
Pretty clear the error messages are misleading/wrong. But, also known that generally you get TPMS errors when default pressure is not set correctly. So why not go set your default pressure in TPMS.
I'd be a lot more concerned about the phantom 12V electrical system service errors reported elsewhere. Then again those are supposedly fixed if your software is up to date. Have you checked that?
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
I haven't had that one, yet. But I've driven mine less than 3000 miles far and I haven't gotten the same error twice so that might be the next surprise Mercedes has for me.
My poor little Ryobi air pump is recovering from inflating the first tire to 40 psi. It needs about 15 mines to cool down before I can do the second one. Anywho, I guess in about an hour or so I'll set the default pressure to that from the current 38. Still doesn't change the fact that the warning was trigger at the highest pressure (and temp, as shown in picture) not the lowest like every other TPMS on the planet. That just plain ain't right.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
Here a picture before I inflated the last tire showing 36.5 psi... someone please explain to me how I could have accidentally reset the default while driving that would result in a warning. If it had been set to 41 as I claim then it should have triggered a low pressure warning when I left not an hour into my drive. And if I reset it while driving the pressure would have been lower than 41 but more than 37 so there's just no way it could have accidentally happened. It seems obvious to me that there's some bad programing here and the only thing I can think of is it stores the pressure and temp when you reset, not just pressure, and then tries to calculate what the pressure should be as the temp goes up or down.
Anywhosies, I'm done, as is my Ryobi which has served me well for five years. I think they quit making these too. :cry:
Last edited by GreasedFolgore; Sep 13, 2023 at 06:14 PM.
the only thing I can think of is it stores the pressure and temp when you reset, not just pressure, and then tries to calculate what the pressure should be as the temp goes up or down.
Anywhosies, I'm done, as is my Ryobi which has served me well for five years. I think they quit making these too. :cry:
Yes, the tire pressure threshold is in relation to the temperature.
And Ryobi has a new version of the tire inflator. I think the new version works better, especially for stopping the pump at the target pressure.
2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
... and you know what else. I had just navigated to a 350 kW EA charger location that my Mercedes said had two available stalls and preconditioned my battery only to find them all taken. So I decided to just drive home on a low battery to charge instead of waiting in line and then this happens. I love how the car drives but it really has been one thing after another. Not all of it Mercedes' fault but still...
Tomorrow I'm gonna go talk to a someone about buying a Jaguar F-Pace. I really did want to go all electric but its just not working out for me, yet. I think this'll be my last ICE vehicle though.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
Grrrr......
It's fixed now, for the time being (I might have to uninstall Intel Unison).
