Tire pressure monitor
#1
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Tire pressure monitor
The tire pressure light come on the dash yesterday and it is not going away. I've checked the pressure few times and it seems to be OK (30 psi front / 34 psi back).
Any idea what might be happening? Does it only display if the pressure is too low or also when it is high?
Any idea what might be happening? Does it only display if the pressure is too low or also when it is high?
#2
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2017 E300
It doesnt check for low, it checks for changes.
You could have it really high and it dropped down to normal and the light would come on.
Suggestion: go to a gas station and measure it with the tires relatively cold and then when you got it all right, push the steering button "right" all the way into system (past navi, audio, telephone). Then under the menus, you can find tire pressure reset and if you click "OK" it will reset it and memorize the current tire pressure you have just set.
You could have it really high and it dropped down to normal and the light would come on.
Suggestion: go to a gas station and measure it with the tires relatively cold and then when you got it all right, push the steering button "right" all the way into system (past navi, audio, telephone). Then under the menus, you can find tire pressure reset and if you click "OK" it will reset it and memorize the current tire pressure you have just set.
#5
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2012 C63 AMG
On a similar topic, does the W204 have TP sensors inside the wheel or does it measure the rotational speed and backwards calculate for the diameter to determine if there is a decrease in size and therefore pressure?
#6
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there are TP sensors inside. this feature actually saved me a couple weeks ago. Since I have low pro tires, its hard to tell if I'm running flat or not. Good thing these babies were able to detect the change in air pressure.
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'14 GLK250 Diesel
Canadian cars got the indirect TPMS [based on rotational speed]; USA cars got the direct system, with sensors buried in each valve.
Unless something's changed for '09....
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#8
Others may disagree, but I cannot use the "reset" mechanism via the trip computer to baseline the inflation pressure more then 3 psi below the recommended inflation pressure on the door. So if its 35psi for the rear, if the rears aren't at least 32psi, the calibration reset will work for a while, but the light will then come back on.
#9
Another point - when you engage the reset via the trip computer screen, let it fully go through the process. There is a point on the screen where you think its complete, and you might then press the OK button. Don't do that, once you engage it - let it complete and then return to the previous screen by itself.
#10
As stated direct TPMS, also ALL cars sold in the United States from 2009-on are REQUIRED to be equipped with tire pressure monitors.
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2012 C63 AMG
Well a good way to tell is if your valve stem is metal or rubber. If its rubber, its definitely rotational as there is no support for such a device. If its metal, then its a sensor inside. Mine are rubber...
#14
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Easy to check if you have the "real deal" Tire Pressure Monitor, check your vehicles datacard 470 or 475 means TP sensors in your wheels, 477 means RPM dependant TPM.
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2011 E550 Coupe
Well, now you guys have me interested. I have 477 and I was going to buy winter tires and rims and was looking at purchasing 4 TPM sensors. Based on what I just read, I do not require TPM sensors?
#16
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Correct.
Also I think that you can read out the actual pressure in the IC display with code 470 or 475 TPM.
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1953 300 Adenauer, 1971 300 SEL 6.3, 1975 600, 1978 450 6.9
Not quite correct.....
...Europe uses a different system from the US....
The American TREAD act requires direct pressure measurement (currently implemented on most cars using sensors in each wheel) as opposed to the RoW that uses a combination of existing sensors to determine the rotational diameter of the wheel. As the pressure goes down, the diameter of the tire changes. This is called the indirect system.
There are a few problems with the indirect system - first, the system needs to be calibrated by the driver and, if the pressure was wrong when calibrated, will not read accurately. Secondly, since the system looks for changes between the tires to determine if one is leaking, it does not show seasonal variances....
The American TREAD act requires direct pressure measurement (currently implemented on most cars using sensors in each wheel) as opposed to the RoW that uses a combination of existing sensors to determine the rotational diameter of the wheel. As the pressure goes down, the diameter of the tire changes. This is called the indirect system.
There are a few problems with the indirect system - first, the system needs to be calibrated by the driver and, if the pressure was wrong when calibrated, will not read accurately. Secondly, since the system looks for changes between the tires to determine if one is leaking, it does not show seasonal variances....
#18
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223.168 & 213.012 & 906.633 & 214.005
...Europe uses a different system from the US....
The American TREAD act requires direct pressure measurement (currently implemented on most cars using sensors in each wheel) as opposed to the RoW that uses a combination of existing sensors to determine the rotational diameter of the wheel. As the pressure goes down, the diameter of the tire changes. This is called the indirect system.
There are a few problems with the indirect system - first, the system needs to be calibrated by the driver and, if the pressure was wrong when calibrated, will not read accurately. Secondly, since the system looks for changes between the tires to determine if one is leaking, it does not show seasonal variances....
The American TREAD act requires direct pressure measurement (currently implemented on most cars using sensors in each wheel) as opposed to the RoW that uses a combination of existing sensors to determine the rotational diameter of the wheel. As the pressure goes down, the diameter of the tire changes. This is called the indirect system.
There are a few problems with the indirect system - first, the system needs to be calibrated by the driver and, if the pressure was wrong when calibrated, will not read accurately. Secondly, since the system looks for changes between the tires to determine if one is leaking, it does not show seasonal variances....
Europe is using both the ESP based tyre pressure loss warning system as well as the one using sensors in the wheels. Our operating frequency on the sensors is different though.
Of course the low cost RDW-option isn't as good as the real RDK or TPMS option, they would not have both if the cheaper one would do everything the more expensive one does.
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S204 C220 CDI, VW Scirocco III 1.4TSI 160
...Europe uses a different system from the US....
The American TREAD act requires direct pressure measurement (currently implemented on most cars using sensors in each wheel) as opposed to the RoW that uses a combination of existing sensors to determine the rotational diameter of the wheel. As the pressure goes down, the diameter of the tire changes. This is called the indirect system.
There are a few problems with the indirect system - first, the system needs to be calibrated by the driver and, if the pressure was wrong when calibrated, will not read accurately. Secondly, since the system looks for changes between the tires to determine if one is leaking, it does not show seasonal variances....
The American TREAD act requires direct pressure measurement (currently implemented on most cars using sensors in each wheel) as opposed to the RoW that uses a combination of existing sensors to determine the rotational diameter of the wheel. As the pressure goes down, the diameter of the tire changes. This is called the indirect system.
There are a few problems with the indirect system - first, the system needs to be calibrated by the driver and, if the pressure was wrong when calibrated, will not read accurately. Secondly, since the system looks for changes between the tires to determine if one is leaking, it does not show seasonal variances....
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2012 US Edition C300 Luxury 4-Matic
#21
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You can try from the Russian site too (if your car is not too fresh for them).
http://old.mbclub.ru/mb/vin/?lng=eng
#22
Yes, it is MANDATORY on every passenger and light truck from 2009-on, even Hyundai's.
#25
Others may disagree, but I cannot use the "reset" mechanism via the trip computer to baseline the inflation pressure more then 3 psi below the recommended inflation pressure on the door. So if its 35psi for the rear, if the rears aren't at least 32psi, the calibration reset will work for a while, but the light will then come back on.
An old post being brought back up actually helped me (I say this as some people get irritated from old topics be re-hashed).
Anyways with my winter tires on my "tire pressure light" kept coming on and I just dealt with it for the time being. I had no idea the factory wheel tire pressures were built into the system to set off the "warning". I assumed different tires could be used and then set the indicator to monitor those pressures(my winter wheels/tires being all the same size and same pressure opposed to staggered like the OEM set-up).
A full day later no light as I set my winter wheels to the factory pressures. Fingers crossed.
I assumed the monitors Tirerack installed in my winter set-up maybe weren't fully compatible but the problem now seems to be fixed.