[volodp]

I had an interesting glitch earlier today and thought I'd share it here. A few minutes into a 1-hour drive the car told me to inflate one of the tyres. When I went into the menu to see which one is deflated, I was very surprised to find out that the car has actually detected the wheels wrong - looks like it thought that my left front wheel is rather the right front wheel, my right front wheel is my right rear wheel etc. when I eventually got to where I was going, I've reset the system and things got back to normal but I thought it's an interesting bug. If I'm not mistaken, a receiver in each wheel arch detects the strongest signal but this must be something else than a wrong sensor being picked up. [IMG][/IMG]

[jad03060]

I think there's only one TPMS receiver these days. The vehicle figures out what's where by deducing how many revolutions there are as you go around corners or curves which is why it takes a while to figure out. That, plus the fact that they don't broadcast constantly (about once every 30-seconds). The ABS sensors help in the scheme to help determine the revolutions, which will differ based on slight changes in direction. IT ends up faster if you're taking a lot of turns versus driving on a relatively straight road.

[bertenyi]

I have had this very same glitch pop up, roughly once a month. I just reset the tyre pressure monitor and it returns to normal.
I have just had a sw update installed, i wonder if that will help getting rid of this…

[jad03060]

With my limited understanding, this shouldn't happen. Each TPMS has a unique ID embedded in it sort of like what is done with Ethernet adapters. Once the computer decides where a unit is installed, it should not 'forget' that until you force a reset.

IOW, it should be something that could be fixed via a software update. Out of curiosity, what version do you have in your vehicle(s)?

[wufpak]

Originally Posted by jad03060

I think there's only one TPMS receiver these days. The vehicle figures out what's where by deducing how many revolutions there are as you go around corners or curves which is why it takes a while to figure out. That, plus the fact that they don't broadcast constantly (about once every 30-seconds). The ABS sensors help in the scheme to help determine the revolutions, which will differ based on slight changes in direction. IT ends up faster if you're taking a lot of turns versus driving on a relatively straight road.

Just wanted to mention that the G05 does have direct RDC (TPMS) sensors for each wheel.
There was a time when BMW vehicles had indirect TPMS, but it's been a while. Those systems also don't show actual pressures, they just alert the driver that the tire has low pressure. I think there has to be a drop of about 10psi for indirect TPMS to generate the low pressure alert.

[jad03060]

Yes, I'm aware of that. The G05 does have 'smart' TPMS sensors, not a passive system (at least in the USA), but as far as I can tell, the previous two BMWs that I had, and assume (you know what that means!) that the current one still only uses one receiver.

[TurtleBoy]

Originally Posted by jad03060

With my limited understanding, this shouldn't happen. Each TPMS has a unique ID embedded in it sort of like what is done with Ethernet adapters. Once the computer decides where a unit is installed, it should not 'forget' that until you force a reset.

That has not been my experience. When I get my tires rotated I do not need to do a reset in order for the new positions to be picked up. Takes a few minutes of driving to update.

[volodp]

Originally Posted by jad03060

Out of curiosity, what version do you have in your vehicle(s)?

Mine is on 03/2022.52, updated OTA just a few weeks ago. Never happened to me before.

[mrjlaunch]

Originally Posted by volodp

Mine is on 03/2022.52, updated OTA just a few weeks ago. Never happened to me before.

Did you ever resolve the issue?

My 2018 G30 alerted me to the tyre pressures but when I checked it had switched the front and back wheel around overnight. I did reset it and two of the wheels switched places, but several resets later and it still shows like yours did, where the opposite wheels are in the wrong place.

[volodp]

Never seen it happen since. Was just a weird one timer I guess.

[jad03060]

On my 45e, this is what the user's manual says about changing a tire:

After the wheel change
1. Tighten the lug bolts crosswise. The tightening
torque is 101 lbs ft/140 Nm.
2. Stow the nonworking wheel in the cargo area,
if necessary.
The nonworking wheel cannot be stored under
the cargo floor panel because of its size.
3. Check tire inflation pressure at the next opportunity
and correct as needed.
4. Reinitialize the Flat Tire Monitor.
Reset the Tire Pressure Monitor again.

[mrjlaunch]

Originally Posted by volodp

Never seen it happen since. Was just a weird one timer I guess.

Thanks for the update.
It's still happening for me, the sensor positions switch overnight every few days. I'm surprised the positions switch at all, I presumed positions only updated when resetting the TPMS system