How does tire pressure monitor know which tire is which?
#1
How does tire pressure monitor know which tire is which?
Interesting thing happened when I replaced all 4 tires and the front right wheel.
After that, the tire monitor shows 2 left at 39 and 2 right at 45 -- the norm is 39 front and 45 at rear. I went to the air pump but they appear to be 39 in front and 45 at rear. I was quite confused and took it back to the tire shop
The guy told me I need to reset. The only thing I can find is to go the tire monitor, press down arrow, choose the use it a new reference. That did not change anything. The guy then connected to OBD and did something. Then it's corrected.
I would guess the tire pressure monitor has some kind of setting to determine which tire is at which position. It has some king of memory and is probably linked to the wheel somehow. The new wheel probably played a role to mess it up.
Does anyone know how this should have worked?
Thanks
After that, the tire monitor shows 2 left at 39 and 2 right at 45 -- the norm is 39 front and 45 at rear. I went to the air pump but they appear to be 39 in front and 45 at rear. I was quite confused and took it back to the tire shop
The guy told me I need to reset. The only thing I can find is to go the tire monitor, press down arrow, choose the use it a new reference. That did not change anything. The guy then connected to OBD and did something. Then it's corrected.
I would guess the tire pressure monitor has some kind of setting to determine which tire is at which position. It has some king of memory and is probably linked to the wheel somehow. The new wheel probably played a role to mess it up.
Does anyone know how this should have worked?
Thanks
#2
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
There are sensors for each tire. The device they used is precisely used to communicate with the sensors.
#3
There is sensor on each tire / wheel.
However, how does the car knows the position of each senor/wheel/tire? Naively, I'd think it's determined by the parts on the car, not the part on the wheel. But if that's the case, I don't see why after replacing wheel/tire, the position was wrong. Or maybe the tire shop messed things up
However, how does the car knows the position of each senor/wheel/tire? Naively, I'd think it's determined by the parts on the car, not the part on the wheel. But if that's the case, I don't see why after replacing wheel/tire, the position was wrong. Or maybe the tire shop messed things up
#4
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
There is sensor on each tire / wheel.
However, how does the car knows the position of each senor/wheel/tire? Naively, I'd think it's determined by the parts on the car, not the part on the wheel. But if that's the case, I don't see why after replacing wheel/tire, the position was wrong. Or maybe the tire shop messed things up
However, how does the car knows the position of each senor/wheel/tire? Naively, I'd think it's determined by the parts on the car, not the part on the wheel. But if that's the case, I don't see why after replacing wheel/tire, the position was wrong. Or maybe the tire shop messed things up
Let me read your original post again.
#5
After the 4 tires and FR wheel (note I have no idea if they put the new one at FR) were replaced, the dashboard showed the following
FL=39 FR = 45
RL=39 RR= 45
According the the air pump, it's
FL=39 FR = 39
RL=45 RR= 45
The tire shop guy used OBD and did something and did not move wheel/tire. The the tire reads correctly
FL=39 FR = 39
RL=45 RR= 45
So in the car computer system, the position of the wheel/tire is somehow messed up (e.g. FR <-> RL).
FL=39 FR = 45
RL=39 RR= 45
According the the air pump, it's
FL=39 FR = 39
RL=45 RR= 45
The tire shop guy used OBD and did something and did not move wheel/tire. The the tire reads correctly
FL=39 FR = 39
RL=45 RR= 45
So in the car computer system, the position of the wheel/tire is somehow messed up (e.g. FR <-> RL).
#6
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
After the 4 tires and FR wheel (note I have no idea if they put the new one at FR) were replaced, the dashboard showed the following
FL=39 FR = 45
RL=39 RR= 45
According the the air pump, it's
FL=39 FR = 39
RL=45 RR= 45
The tire shop guy used OBD and did something and did not move wheel/tire. The the tire reads correctly
FL=39 FR = 39
RL=45 RR= 45
So in the car computer system, the position of the wheel/tire is somehow messed up (e.g. FR <-> RL).
FL=39 FR = 45
RL=39 RR= 45
According the the air pump, it's
FL=39 FR = 39
RL=45 RR= 45
The tire shop guy used OBD and did something and did not move wheel/tire. The the tire reads correctly
FL=39 FR = 39
RL=45 RR= 45
So in the car computer system, the position of the wheel/tire is somehow messed up (e.g. FR <-> RL).
#7
could it be possible that each wheel's sensor transmit to receiver near that particular wheel area so it does not matter even if the wheels are rotated, the receiver location is fixed. The ECU will get the correct corresponding info from that particular fixed position receiver.
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#8
If I'd design this, I'd set the position information at the receiving end in the car. The sensor tells the receiver. This way rotation would not require any change in the car.
But given the wrong reading I saw, I'd say that's not the design. And each time they rotate the tire, you have to go into OBD to do something. This sounds wrong.
But given the wrong reading I saw, I'd say that's not the design. And each time they rotate the tire, you have to go into OBD to do something. This sounds wrong.
#9
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
There is also a handheld device that you can assign values to the TPMS sensors and adjust accordingly, it is solely designed for that purpose.
As for your design, it is a great one, a receiver receiving sensor information based on the distance on the two axis seems like a good idea. That way, it can predict where is each sensor and on which wheel but there might be technical limitations that made engineers design it to use the method that is being used now. Interesting idea nonetheless.
As for your design, it is a great one, a receiver receiving sensor information based on the distance on the two axis seems like a good idea. That way, it can predict where is each sensor and on which wheel but there might be technical limitations that made engineers design it to use the method that is being used now. Interesting idea nonetheless.
#10
For all practical purpose, this means each time they rotate or replace wheel/tire, you'd have to pay a bit attention to the tire pressure monitor. In my case, it alerts right away that the left rear one has issue.
#12
That was what happened to me. I saw the air pressure incorrect after the car is out of the shop. So I tried to use air pump to correct it but it does not move as expected. So I had to go back to the guy in the shop who also tried air pump first and then went with OBD.