about TPM malfunction

[jz]

Today when I was driving I got a TPM malfunction warning in my M8c. I was little bit nervous as I was driving on the highway, but it disappear after 3-4 minutes. I just checked the tire pressure they are all good. Anyone has this issue before? Do I need to worry about it?\\THX

btw I installed my winter tire in October last year, but this is the first time warning appear.

[M3SQRD]

Was it cold this morning? Sometimes you’ll get the error on cold mornings and then as you drive you continue to build up temperature/pressure, causing the TPMS warning light to disappear. Visually look at your tires to see if the one with the TPMS warning is flat/low on pressure.

Recently my wife was driving and she got a TPMS warning showing one tire was at 24 psi and then just a few seconds later it was 11 psi…she immediately pulled over and found an entire key sticking into the tire!

[jz]

Originally Posted by M3SQRD

Was it cold this morning? Sometimes you’ll get the error on cold mornings and then as you drive you continue to build up temperature/pressure, causing the TPMS warning light to disappear. Visually look at your tires to see if the one with the TPMS warning is flat/low on pressure.

Recently my wife was driving and she got a TPMS warning showing one tire was at 24 psi and then just a few seconds later it was 11 psi…she immediately pulled over and found an entire key sticking into the tire!

it was about 5 degree in the morning. I just checked all four and they are 33.1 psi. I am assuming it is just an error like you mentioned?

[M3SQRD]

Originally Posted by jz

it was about 5 degree in the morning. I just checked all four and they are 33.1 psi. I am assuming it is just an error like you mentioned?

Yep. Temperature changed enough from when the tire pressures were first set to cause a TPMS error. One must have been slightly colder and it hit the threshold to throw a TPMS error. You’re good to go.

[fe7565]

Also, I believe that the TPM measures "relative" pressure and not primarily a pre-set pressure. That means that if your last pressure reset was at 33psi then it will look for a -4psi change (just an example number) and it will warn below 29 psi. But if you reset it last time when the tires had 35psi, then it will warn you below 31psi and not below 29psi.

That's why in moderate climates I need to add air when winter comes, and take out air when spring gets here. In your case in Canada: add air in early September and take air out in late June

[M3SQRD]

Originally Posted by fe7565

Also, I believe that the TPM measures "relative" pressure and not primarily a pre-set pressure. That means that if your last pressure reset was at 33psi then it will look for a -4psi change (just an example number) and it will warn below 29 psi. But if you reset it last time when the tires had 35psi, then it will warn you below 31psi and not below 29psi.

That's why in moderate climates I need to add air when winter comes, and take out air when spring gets here. In your case in Canada: add air in early September and take air out in late June

Every time you perform a TPMS reset, the reference pressure for each tire is based on the pressure in each tire at the time of resetting. TPMS warning pressures are also redefined at this time. I believe it takes a while for the system to fully reset because it’s tracking the revs per mile as a backup to the TPMS pressure sensor. It takes a long time to reset if you’re driving 10-30 mph whereas the reset is completed fast when moving at 40-60 mph. If it was just pulling a reference pressure, the reset would be quick and its duration would be fixed, not influenced by how fast or slow you’re driving.

[jz]

Originally Posted by M3SQRD

Every time you perform a TPMS reset, the reference pressure for each tire is based on the pressure in each tire at the time of resetting. TPMS warning pressures are also redefined at this time. I believe it takes a while for the system to fully reset because it’s tracking the revs per mile as a backup to the TPMS pressure sensor. It takes a long time to reset if you’re driving 10-30 mph whereas the reset is completed fast when moving at 40-60 mph. If it was just pulling a reference pressure, the reset would be quick and its duration would be fixed, not influenced by how fast or slow you’re driving.

very sadly, the tire malfunction warning appear yesterday and today again, and it went back to normal after I reset and perform tire test. Just like you said, the sign seems only appear when I enter the highway(high speed), and it disappears after I reset and enter the highway. So I guess it might be something wrong with the sensor since my tire pressure are good everytime I reset.

[jz]

Originally Posted by fe7565

Also, I believe that the TPM measures "relative" pressure and not primarily a pre-set pressure. That means that if your last pressure reset was at 33psi then it will look for a -4psi change (just an example number) and it will warn below 29 psi. But if you reset it last time when the tires had 35psi, then it will warn you below 31psi and not below 29psi.

That's why in moderate climates I need to add air when winter comes, and take out air when spring gets here. In your case in Canada: add air in early September and take air out in late June

Thanks for explanation, but is it supposed to show the tire pressure instead of just tell you tpm malfunction?

[M3SQRD]

Originally Posted by jz

very sadly, the tire malfunction warning appear yesterday and today again, and it went back to normal after I reset and perform tire test. Just like you said, the sign seems only appear when I enter the highway(high speed), and it disappears after I reset and enter the highway. So I guess it might be something wrong with the sensor since my tire pressure are good everytime I reset.

You should see temperature and pressure at all four tire locations. Yes, you likely have a damaged sensor(s).

[DomMuc]

your dealer can read the sensors seperately with the RDC-Tool

[fe7565]

If you have Bimmercode or similar, you can set the TPMS to display both the pressure and temperature next to each tire on the screen.

[co_440i]

Originally Posted by fe7565

If you have Bimmercode or similar, you can set the TPMS to display both the pressure and temperature next to each tire on the screen.

What module is this under? I assume it's an advanced function

[fe7565]

Originally Posted by co_440i

What module is this under? I assume it's an advanced function

If I remember correctly, it’s not under the advanced function. I think it’s under FEM.

[fe7565]

Originally Posted by co_440i

What module is this under? I assume it's an advanced function

BimmerCode


“Headunit” HU_CIC control unit


• Pressure and temperature in tyre pressure monitor
Enable/disable the pressure and temperature in the tyre pressure monitor in the iDrive system. Please note that the car has to be equipped with the required sensors. This option affects the display only and it is not possible to completely deactivate the tire pressure monitoring in the car.
Values:
o Active
o Not active

Requirements:
o “Headunit” HU_CIC control unit
============================================


Head Unit NBT/EVO:


• Tire pressure control
The displayed values of the tire pressure control in the iDrive system. Please note that the car has to be equipped with the required sensors to make this work.
Values:
o Display pressure only
o Display temperature and pressure
o Not active

Requirements:
o “Headunit” HU_NBT or “Headunit” HU_NBT_EVO control unit

[DanG]

Originally Posted by fe7565

If you have Bimmercode or similar, you can set the TPMS to display both the pressure and temperature next to each tire on the screen.

My M2 has this display with no coding.

[mbferrari]

I got a low pressure warning and sometimes got it when it got really cold in garage. Now I get it every day. Inflated tires to 35psi in all 4 corners, RESET AND DROVE AROUND UNTIL 100%. Still every time at startup I get low pressure message -- Help please.

[fe7565]

Originally Posted by mbferrari

I got a low pressure warning and sometimes got it when it got really cold in garage. Now I get it every day. Inflated tires to 35psi in all 4 corners, RESET AND DROVE AROUND UNTIL 100%. Still every time at startup I get low pressure message — Help please.

Next morning before you start the car measure each tire manually with a tire pressure gauge. See if there’s any difference of more than 2 to 3 psi between anyone of them.

[mbferrari]

Originally Posted by fe7565

Next morning before you start the car measure each tire manually with a tire pressure gauge. See if there’s any difference of more than 2 to 3 psi between anyone of them.

I will do that today, but that has not been the case previously.