ss3964spd

Bought the car, a 2011 E550, with about 20k miles on it, selling dealer (BMW) replaced all 4 tires. TPMS functioning normally.
Just over a year ago the right front TPMS sensor went missing. Dash displayed correct pressures for the remaining 3, and showed TPMS Sensor Missing for the right front. decided to live with it until the tires needed to be replaced.
Fast forward to Sat, 10/28: Brand new Michelin Pilot Sport A/S 3+ installed by local tire shop. Since one was dead I decided to have all 4 TPMS sensors replaced given they are about 7 years old. Tire shop used Schrader brand "EZ-sensor", P/N 33500.
Initiated the reset through the dash, and the yellow tire light remained on of course. 8 ish miles later: "Tire Pressure Monitor Inoperative No Wheel Sensors". Yellow tire remains on.
It sure seems obvious to me. System was working fine before the tire and sensor change, and now it can't find any sensors.

The quick question is this: does the TPMS system need to be reset using SDS? I've read a dozen TPMS threads here and I haven't seen a single thing that said SDS will solve it.

Many thanks,

Dan

KEY08

Keep driving to see if they will actuate. It may take several more miles, unless you are already beyond the 8 miles. I installed some new tires and wheels in the spring for the summer and ordered Schrader sensors model no. A0009054100 (433.92Mhz). I reset the system on the MFD and waited for probably 20 miles before they recognized all sensors. It has been perfect since. No SDS reset required at all.

ss3964spd

Thanks for the feedback Key. Between errands on Sat and Sun, plus the drive into work this AM, I've got well over 20 miles on the new sensors.

And thanks for confirming the SDS question.

Dan

Arrie

Funny this happened to me just two weeks ago. I had new tires installed on my original MB rims and decided to keep the sensors on my 17" rims as those tires still have plenty of life left. This shop got MB sensors based on my VIN number. They installed everything but then they could not read the sensors with their tool at each tire. Without even driving the car they went to get other sensors and installed those. Their tool read them just fine but the car did not read them. Firs the tech went for a 10 minute drive but the system did not work. I went to drive and after about 15 miles I get message "TPMS sensors missing". Went back and sensors were replaced again with ones based on the VIN and again the tool could not read them. The technician went to drive the car and even went to a MB Indy shop and even they did not know how to fix it. They gave the car back to me and asked to stop by that Indy shop again and on my way there (about a mile) the pressure readings popped up in the cluster.

By this shop there are two frequencies on the sensors that they read with the tool but based on what happened there must be another one in use in my car.

ss3964spd

Interesting indeed Arrie.

I had a conversation with Schrader tech support a little while ago. As I mentioned above, the tire shop used Schrader sensors, #33500. According to tech support that sensor, which is a "programmable" sensor (it broadcasts in 3 different frequencies, and other parameters) the installing tech must program it with a programming tool to the vehicle. He further stated that, according to his documentation, the 33500 cannot be programmed to my 2011 E550. The Schrader tech further suggested that their model 28214 sensor be used; it is a direct replacement for the OE and is pre programmed. Finally, he confirmed that if a sensor is programmed, or pre programmed correctly the vehicles TPMS system does not need to be "reset" using factory diagnostics (AKA SDS).

I'll be stopping by the tire shop this evening.

To add insult to injury, the tire shop charged me 3X the price for each sensor. The 33500 is available at local stores and across the internet for about 50.00 Ea. They charged me 150.00 each. Ouch. My own fault, while I price shopped the tires I didn't shop the TPMS sensors. Regardless, I've sent their corporate office an email.

Dan

KEY08

Yikes! Not good. Schrader is an OEM supplier to Mercedes. My sensors have the Star logo molded right onto them. I paid $110 for 4 sensors on Amazon.

paintwerks_au

Interesting. My MY12 E350 sedan does not have tyre pressure sensors. Instead, the ECU/BCM picks up on the rotational speed of the wheel. If the tyre pressure is low, it'll give you a warning on the instrument panel.

KEY08

How do you go about setting the pressures or determining how far the pressure has fallen in a deflating tire?

paintwerks_au

Great question! TBH, I don't know how the system works it out. However, I had new rims and tyres fitted recently and the pressures were set high than standard, but at the same rates front to rear (if the placard called for a higher front setting). I gather the car works out the rolling diameters and has a +/- tolerance which would account for increases/decreases in pressure due to ambient conditions and also the heating of the air in the tyres when the car is driving. It likely uses the ABS wheel speed sensors to compare the rolling rate against each tyre when the wheels are pointed straight and the car is at a constant speed.

The day I had the wheels put on, the car did display a tyre pressure low message, but I simply restarted the car, drove it, and it hasn't reported any errors since. I gather the car had to calibrate/adjust.

Arrie

I think it is only in the U.S. where the actual tire pressure must be read. Elsewhere in the world it is common to monitor wheel speed difference as the radius of the tire changes with changing tire pressure. I think this came from the time when we had some Ford SUVs rolling and killing people with failing Firestone tires and they blamed it on low tire pressures.

I'm sure someone knows the facts here in the forum...

KEY08

This is interesting. I’m going to try and read up on how that system works. It would need to accommodate staggered setups and tire rotations. Each tire must be treated as its own individual bubble and monitored for any significant rotational change.

MW4matic

If the tips are fragilely cracked or broken then It would be the monitor in the sensor itself. It does wear out over period of time, like a battery.

ss3964spd

Issue resolved. The tire shop procured and installed the Schrader 28214 sensors and the yellow tire warning light extinguished itself within blocks of driving the car, and read out the tire pressure shortly there after. No SDS "reset" of the TPMS system was needed. The tires were over filled, of course (for max load) but that was easily remedied.

BTW, the Michelin Pilot Sport A/S 3+ are really nice, much better than the OE Continentals. I also had all 4 road force balanced - well worth the 25.00/per tire up charge.

Lord Mighty