Tyre Pressure Sensor Query

[mbenz76]

Hi All

I have 2010 E350 with TPMS fitted. Had the car since new and changed the tyres a couple of time (always by main dealer).

Had the rear drivers tyre start losing pressure over the week. While pumping tyres up I broke the opposite side valve removing pump. That one isn't leaking but needs replacing.

Took it to main dealer today (usually reasonable for me and handy) and they diagnosed a leaking valve on the one losing air and a new valve (as expected) on the other side.

Not a problem you might think.

I have been told the valves are "special" because of the TMPS sensors and that they may also damage the sensors when doing it, so worst case scenario is two valves and two sensors running at £160.

Now my problem with that is that I used to have a Renault with TPMS which has the same fancy valves and sensors and the Renault dealer always used to warn of the same potential issue. That said they never did break a sensor.

The Renault used to give pressure readings immediately as it had sensors. However the Mercedes tells me I have to drive for a while first. I thought because it didn't have sensors but instead ised the ESP to detect centrifugal force and measure the pressure. Therefore not needing fancy valves and sensors.

Can anyone please confirm whether my E350 is likely to have physical sensors and valves or whether it does use the ESP? Or how I may find out. Don't think the dealer is trying to rob me but not sure they are correct in their assumption of what it has installed either.

Thank you

 

[C43AMG]

You have TPMS. I have them on both cars and they don't activate until you have driven a few miles. Especially after replacing tyres.

 

[Alps]

sensors should not need replacing, valves are about £12 +vat each

 

[KillerHERTZ]

Sorry to hijack thread, I have the error on my dash constantly (the orange picture of the tyre) do I need new valves or replacement battery/sensor packs?

 

[mbenz76]

You have TPMS. I have them on both cars and they don't activate until you have driven a few miles. Especially after replacing tyres.

I know I have TPMS. I was querying whether it was likely to be the direct (ev sensors on valves) system or the indirect (ESP based) system.

Called MB customer service who confirm it does have sensors and valves.

If that is the case why do I have to drive a short distance (300 yards maybe) before it shows readings when my old Renault I had 12 years ago showed pressures with engine off stood cold on drive as long as electrics were on!

 

[mbenz76]

sensors should not need replacing, valves are about £12 +vat each

I agree they shouldn't need changing. I assume just their disclaimer in case they break them and have to replace them.

When I owned Renault they always said the same - and never broke one despite their terrible standard of work - so I am hopeful for just the two valves needing changing.

They are quoting something like £30 each for valves. And £40 each for sensors if they break when being split from the valve. £30 is steep but is all in and I can't be bothered shopping around as I need it done quick.

To be fair, Renault used to say it would be something like £125 per wheel if they broke!

 

[merc estate]

i just looked on ecp they want £124 each YIKES quick get down to MB dealer.

 

[SteveTheViking]

I have TPMS valves etc but one has a broken valve barrel (that the valve cap normally screws onto). Everything is presently working OK but eventually the valve barrel will snap off. Can i replace the valve body and/or the barrel without completely replacing the TMPS sensor.

 

[mbenz76]

It was only my valve stems which were at fault.

They are a seperate part to the sensor but because mine were 4 years old they had basically corroded together. They had to angle grind them apart thus destroying the sensor.

Others may have better luck, but do prepare for worst case.

 

[developer]

I have TPMS valves etc but one has a broken valve barrel (that the valve cap normally screws onto). Everything is presently working OK but eventually the valve barrel will snap off. Can i replace the valve body and/or the barrel without completely replacing the TMPS sensor.

Yes you can Steve - it is a separate part, as mentioned by others above.

Welcome btw.

 

[grober]

The discrete sensor type usually have internal batteries [ which cannot be changed] and will therefore wear out eventually. I have heard 5 years as a projected life. Obviously not being activated all the time will help prolong battery life and allowing some time for tyre pressure to reach operating pressure might not be a bad thing either to prevent false alarms??