How is temperature measured ? TPMS ?

[Jibbajabba]

I intend to buy some alloys from wheelbase including fitted tyres. As I want to be able to switch them around I asked them about TPMS and they offer the install of TPMS for £100.

Apart from the fact that I think those are a bit cheap - I think - are TPMS universal and will they even work ? Is the TPMS the one that measures the temperature of the tyre ?

 

[Deleted member 149005]

No TPMS is Tyre Pressure Monitoring System. There are, generally, 2 types:

- uses a pressure sensor in the tyre valve to monitor pressure against a preset value (hence the need to reset whenever the tyre pressures are adjusted). These units then display the tyre pressure values on a separate display, either built in to the vehicle dash or a separate unit if aftermarket

- a cheaper, simpler, alternate which uses the ABS sensors to identify any change in speed across the axle; it works on the premise that a tyre losing pressure will have a smaller diameter and therefore a small circumference
and therefore will rotate at a different (faster) rate. Again, these the need to be reset whenever the tyre pressures are adjusted

 

[Jibbajabba]

Thanks - that I kinda knew - but how does it measure temperatures of the tyres. I just want to make sure that if the shop fits tyres with TPMS it all works so I don't have to go to a shop anyway

 

[Deleted member 149005]

Thanks - that I kinda knew - but how does it measure temperatures of the tyres. I just want to make sure that if the shop fits tyres with TPMS it all works so I don't have to go to a shop anyway

it doesn't measure temperature....

 

[Jibbajabba]

Cool. Do you know how it does ?

 

[Deleted member 149005]

how it does what???

I am not aware of anything that measures temperature on road tyres..

 

[Jibbajabba]

@greenmanslk Apparently my e63s does

 

[Deleted member 65149]

Tire Infrared Temperature Sensors

Infrared sensors for measuring surface tire temperatures. Up to 16 Channels at 32Hz with object temperatures between -20 to 300˚C and data sent via CAN.

www.izzeracing.com

 

[Deleted member 149005]

well i didnt know that

I'm assuming those temps are for the air in the tyre... not the temp of the rubber?

I suspect you will need the MB specific sensors to be fitted and coded via STAR - i think the sensors are c£100 each and probably another £100 to code to the car..so £500 all in??

 

[GLK]

There are definitely temperature sensors in my (aftermarket) TPMS:

 

[Jibbajabba]

Well that's the question really isn't it

Based on what @knighterrant posted it seems to be an infrared sensor so probably in the wheel arches ... I was wondering what temperature it is - rubber surface or air .. From driving perspective I would THINK it surface temperature is more important - but then again, maybe not

Having now said that - based on what @GLK says it seems to measure air temps.

I think no matter how I look at it - it seems £100 / set via Wheelbase seems too low to be proper / working TPMS - they claim it is compatible .. I just want to go the easy way - I mean if they work they work - I just want to avoid having to go to Mercedes just for the sensors as they probably want to keep the car all day.

Actually might ring them ...

 

[Jibbajabba]

So Mercedes doesn't know lol - they says that the GT cars have the temp. sensor included in the pressure one but e63s - they don't know ... funny that - even looking through various online catalogs - there is no such thing as a tyre temp. sensor so who knows where the things gets it from.

 

[whitenemesis]

I believe many TPMS sensors also include a temperature sensor within the valve body. It's all in the same unit. Even if the dash doesn't display tyre temp it is available via the OBD port. It may even be possible to recode the system with STAR to display on the dash, especially if it is available on other models. I doubt very much MB would spec and source different TMPS sensors for the different models

 

[Jibbajabba]

Now I guess the question is - does every TPMS have that - I guess I can only try and see if the temps are missing using the shops' TPMS ...

 

[markjay]

I believe many TPMS sensors also include a temperature sensor within the valve body. It's all in the same unit. Even if the dash doesn't display tyre temp it is available via the OBD port. It may even be possible to recode the system with STAR to display on the dash, especially if it is available on other models. I doubt very much MB would spec and source different TMPS sensors for the different models

Yes.

I bought after-market TPMS and there's a temp sensor inside the assembly. I would imagine that original MB TPMS does the same.

 

[markjay]

I intend to buy some alloys from wheelbase including fitted tyres. As I want to be able to switch them around I asked them about TPMS and they offer the install of TPMS for £100.

Apart from the fact that I think those are a bit cheap - I think - are TPMS universal and will they even work ? Is the TPMS the one that measures the temperature of the tyre ?

What TPMS are they installing?

Avoid the ones inside the valve cap... they are unsafe. Go for the ones that are incorporated into the valve base.

Also, some connect to your iPhone over Bluetooth (more expensive type), others connect to a cigarette-lighter-based display over RF (these are cheaper).

The only downside of TPMS BTW is that you can't rotate the wheels front-to-back very easily (though if you have staggered wheels you can't do that anyway).

 

[whitenemesis]

The only downside of TPMS BTW is that you can't rotate the wheels front-to-back very easily (though if you have staggered wheels you can't do that anyway).

Doesn't the MB system automatically recognise the sensor position?
On my Lexus the car detects the sensor location by pinging the sensors and calculating the distance, so easily knows when one rotates wheels.

 

[markjay]

Doesn't the MB system automatically recognise the sensor position?
On my Lexus the car detects the sensor location by pinging the sensors and calculating the distance, so easily knows when one rotates wheels.

My after-market TPMS doesn't... never had a Merc with a genuine one, so I can't comment.

 

[normanh]

You don’t need them coded the car recognises them within minutes of driving after being fitted I used a set off eBay on my c205 never had an issue. If the tyre people are fitting them for 100 that’s a good deal.

 

[Jibbajabba]

You don’t need them coded the car recognises them within minutes of driving after being fitted I used a set off eBay on my c205 never had an issue. If the tyre people are fitting them for 100 that’s a good deal.

Yea it is. But one thing I cannot figure out is whether the generic ones do temps as well. I might just get the alloys, winter tyres and ask Mercedes to switch em around and fit official TPMS. Unless someone got the s/n ...