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A couple years ago I got aftermarket wheels (on a 453) and there weren't any 453 TPMS sensors in the USA.
I grabbed a set of Mercedes sensors for $50 (for 4) and had those installed with the tires.
The 453 dash showed the TPMS light on, but also displayed 'Tire Pressure Monitoring System not present'.

At that time, I was faced with $210 per sensor from the local smart center or $130 per sensor from the tire shop that installed the tires. The $130 sensor is pre-programmed and what came in from Germany was the actual Smart sensor for the 453.

The tire shop got the sensors in the wheels, remounted and balanced all four wheels for free, but the sensor bill was $520... It would have been $1200+ if I had it done at Mercedes...

So talk to the shop where you got your tires.
They will usually put them in for free if you bought both the tires and the TPMS sensors from them.
The 451 sensors 'should be' ~$50 for 4.
I got this set right here in front of me (433Mhz) if you want to try to see if the 451 computer reads them. (they would have to be installed and pressurized though...)
These were the ones that the 453 computer didn't read.

For the future; always replace tires with TPMS sensors in hand.
To the tire tech, that sensor is just a 'valve stem', and usually the shop you bought the new tires from will put them in for free.

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There is another TPMS fault that could be happening.
If One TPMS sensor is bad, i.e. the 451 conputer / reciever is not getting a signal from no battery life left in One sensor;
it can display the fault code 'Tire Pressure Monitoring System not present' or similar for the 451.

The tire shop needs to try reading each wheel in their scanner, And Show You, on their scanner which one is bad or all four are not reading.

What I'm leading to is the tire shop scanner will show the psi of each wheel if the scanner is set up correctly.
Once this is ruled out, if the tire shop scanner is reading all four TPMS sensors, and the TPMS light is still lit up in your dash, it might be a problem with the 451 reciever (of the 433Mhz sensors).
And that would be a MB STAR unit diagnosis...
 

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2008 Passion Coupe "Lewis Hambach"
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I have a 2008 and the TPMS sensors are still working? ... I probably jinxed myself now ... :unsure:
 

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Discussion Starter #23
I got a second opinion today. Turns out the left front is dead, but the other three are sending a signal. Not sure what I will do. I'm leaning to just letting it go until I get new tires in a couple of years. I'm pretty good about checking tire pressures on my cars and really hate it when features such as these are forced on me, because some people are too incompetent/lazy to check their tires themselves.

In the meantime I'll look around for a set of four Schrader 28214 sensors to have when/if I decide to do the deed. Is the battery in these things active as soon as it is installed or is it only active when the tire is rolling? It obviously sends a signal with the car at rest, but does that signal stop eventually if the car is not moving? I don't want to buy a set of sensors, have them lay around for a couple of years and find the batteries are dead.

Len
2014 EV Coupe 20,000 miles
2014 EV Cabriolet 19,000 miles
 

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Discussion Starter #24
This article answered a lot of my questions about battery life.

TPMS Life Expectancy

The estimated life expectancy of an OE TPMS sensor is 5 to 12 years, with the average lifespan being 7 years. TPMS life expectancy is directly related to the number of radio frequency transmissions the sensors make. Driving habits greatly influence the number of RF transmissions a sensor makes in its lifetime. For example: sensors usually transmit when the vehicle is stopped and transmit more often when in motion. Maintaining a constant speed, such as when you're on a highway, reduces the demand on TPMS sensors and allow the sensors to transmit less often. Drivers who often find themselves driving in start-and-stop type traffic will have a greater impact on the vehicles tire pressure monitoring sensors. Weather can also have an impact on tire pressure sensor battery life. Cold conditions allow batteries to last longer. Warmer conditions take more of a toll on TPMS battery life.

Len
2014 EV Coupe 20,000 miles
2014 EV Cabriolet 19,000 miles
 

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When I purchased my 2014 the TPMS was lit. The person I purchased it from said the tire shop said the sensors needed replaced. I checked the pressure and found the rear to have 32 pounds of pressure. I pumped them up to 36 and the sensors went off. Surprise, just 4 pounds low. It may be worth looki at. Just my 2 cents.
 

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Discussion Starter #26
I'm pretty anal about car maintenance including tire pressure. So the psi of the tires is fine, 36 in the rear and 32 in the front. The TPMS warning has two different warnings. One is for low tire pressure. The other is for a faulty sensor. Mine is showing a faulty sensor(s).

Len
2014 EV Coupe 20,000 miles
2014 EV Cabriolet 19,000 miles
 
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