Gus_Smedstad

I switched to winter wheels / tires on my 2018 GTS, and the car isn't seeing the TPMS sensors after I told it that I'd changed tires. The sensors I'm using are OEM Porsche, and worked fine with my 2014 C4S. My experience is that the car usually recognizes a new set of sensors within a mile, and I've driven about 5 with theses.

Did handshaking change with the 991.2's? I know the frequency is still 433 Mhz.

LexVan

Gus, try changing the comfort setting, and then go back to another setting. It may wake them up. Don't do it near other cars with TPMS.

verstraete

When I had a Porsche dealer mount the winter wheels and tires from my 991.1 on my 991.2, it did not recognize the sensors. Told that 991.2 sensors were required, I purchased them from the Tire Rack. The dealer installed them and they were recognized. I am now in my second winter with them, without further problems.

2001f4s

Gus,
991.2 cars, some are 433mHz, others use 315 mHz.

Call Suncoast with your VIN and they can confirm your frequency.

subwoofer

I bought the 19 inch Porsche wheels and tires from the dealer for my 18 C4S. Went into tire settings and changed it to 19 inch wheels and after a few miles, the sensors read correctly. The dealer had left them with the 20 inch wheel settings.
I don't know if the sensors have changed but they should read right away. With the new ones, a pressure reading isn't displayed until you are in motion at >15 mph.

Gus_Smedstad

I'm aware that you need to be above 15 MPH for the sensors to read. Even if I didn't know that from prior cars, the TMPS screen displays that pretty prominently after you tell it you've changed tires.

Gordon Shumway

Based on my experience with Porsche TPMS, I don't think 5 miles is always enough. I did a simple seasonal readjustment to my tires this past week. The first action after was a 75 mile round trip (150 mile total). About 30 miles into my trip one sensor was several lbs. off the other three. Nothing dangerous so I let it go. Just before I got home about 150 miles later, I thought to check it again, and sure enough they all read the same at the expected +3 lbs. to cold setting.

Valvefloat991

The 991.1 and 991.2 TPMS sensors are different. I don't know if it's frequency or something else, but last year, TireRack shipped the winter tires and wheels I ordered for my 991.2 with the .1 sensors and the system didn't find them. We replaced them with .2 sensors and they worked perfectly.

Gus_Smedstad

1/2 mile was enough with my wife's 2015 Cayman S, with my 2014 C4S (sold for this car), and with my 2015 Panamera SeH (sold to buy the 2014 C4S). Which is why I assumed I definitely had a problem after 5 miles. I'm willing to give it more distance, but I'm really expecting there's a handshaking difference.

That was the experience I had with the Panamera. I bought some off-brand TPMS sensors for the winter wheels that were spec'd for 2010-2013 and they didn't work, even though they were the same frequency. I ordered some 2014+ sensors for Suncoast and they worked perfectly.

I honestly can't figure out why they'd change them, since TPMS sensors are pretty simple things as electronics go. But like a lot of stuff these days, they clearly involve some basic processors, rather than just being plain transmitters. Otherwise there wouldn't be this issue with model year mattering so much.

bwiele

I bought a pre-owned set of winter wheels/tires (center locks) for my 991.2 GTS that were previously used on a 991.1 GT3. I've had the same experience - the TPMS sensors aren't compatible. I'm only planning to drive the car when the roads are dry and not too salty during the winter, so I'm just going to tolerate the error message and the constant yellow warning light for this winter and I'll have the sensors replaced with a compatible set for next winter. I change the wheels myself, and I don't want to pay the silly prices the dealership will charge to take the wheels off to swap them and then put them back on. I can live with it for a few months.

Gus_Smedstad

My local National Tire and Battery has been charging me $20 to change a set of 4 wheels. It's hard for me to argue with that. I don't think they'd be able to handle centerlocks, though. Not because it's complicated, but because they don't have the right tools. They make a big deal out of dealing with my cars so I don't think they service any other Porsches.

I've ordered some 991.2 sensors from the Tire Rack. Since it's going to cost the same for NTB to dismount the tires, replace the sensors, and re-mount them whether I do it now or next winter, I'll have 'em do it when they show up. I'd only really be saving money if I waited until I had to replace the tires due to wear.

inspired626

The 991.1 and 991.2 TPMS are different. They both operate at 433 mhz. The 'handshaking' is different, that is why your 2018 did not recognize the 2014 TPMS.

FYI, ALL Porsche's manufactured for US sale only use 433 mhz. Porsche's that use 315 mhz TPMS are built and sold primarily in Asia.

bwiele

How much were the sensors from TR if I may ask?

And the reason I'm waiting is because my winters are already on my car. I'll wait until I swap them out in the spring because it's just not that big of a deal...

Gus_Smedstad

The Tire Rack sensors are $228 shipped. There are cheaper third-party sensors out there, like for sale on Amazon for $160, but I'm confident the Tire Rack sensors will work and not so sure about a random set for sale with no customer testimonials.

Suncoast wants $560 for a set (including the valve stems, which are $100), and I'm not even sure if they'll work, since the ones they list say "2012.5 or newer," which is wrong. Oh, sure, they'd probably work, since they're a Porsche dealership and they do check VINs for those, but it's still disconcerting that the web page for the part is wrong.

boatracer