About TPMS (Tire Pressure Sensors): Are Aftermarket Ones Okay?

Since our Cayenne’s summer tires are on 20-inch wheels, I asked my husband, “Why did you choose 19-inch wheels for the winter tires?” and he said:

Because 19-inch wheels and tires are cheaper than 20-inch ones. I don’t care about looks for winter tires, and when it comes time to replace worn tires, cheaper is better. Also, I don’t dislike the design of these 19-inch wheels—they actually look more SUV-like, which I like.

He also bought tire pressure sensors on Yahoo Auctions. Porsche’s genuine sensors for four tires are quite expensive, so he got compatible new sensors for about 20,000 yen.

Since my knowledge is limited, I thought, “When you switch wheels or tires, the tire pressure automatically shows up on the car’s meter, right?”

So I asked, “Why do you have to buy tire pressure sensors separately? Aren’t they already installed on the car?”

Modern Porsches have tire pressure sensors installed in the wheels, but the wheels I bought had the sensors removed by the previous owner. So if I left it as is, every time I start the engine, a tire pressure system warning would appear, which would be annoying. That’s why I decided to buy and install separate sensors.

I see…

If I had bought a Porsche myself, I would have had no idea about this and would have been surprised by the tire pressure warning as soon as I switched to winter tires. I’d probably rush to the dealer, buy sensors, and have to remove and reinstall wheels and tires again, which would cost a lot… lol

However, my husband said about the non-genuine sensors:

I read online that “you need to clone the sensor ID” or “setup is required”, so I was nervous about buying them. But the product description said, ‘Programming is done, and the vehicle will automatically recognize the sensors after driving at speeds above 25 km/h for a few minutes.’ I trusted that, drove for about 20 minutes, and it recognized them without any problems. I was relieved. The pressure readings were also very accurate, matching the air gauge closely, so I think they’re quite reliable. By the way, to register new TPMS sensors, you just need to change the setting on the car’s screen from ‘20-inch Summer Tires’ to ‘19-inch Winter Tires’ and then have the car recognize the new TPMS. If you want to keep the old setting and sensors, you’d have to clone the existing IDs, but I don’t see the point. It’s better to just register the new TPMS normally.

Now that winter driving with the Cayenne is possible, my husband plans to go skiing with a friend in February to test the actual driving performance.

So far, on regular roads, the tires feel very smooth and no different from summer tires, but I’ll write a review after driving more.