Why would it show the spare!? :rofl: The system shows the tire pressure for your safety while driving on those 4 tires. If one of those tires fails, you move the spare to that spot and the system will pick display it.The reason I ask is the dash only appears to show tire pressures for the four wheels on the 2013 evic display.
While the is a TPMS sensor in the spare the system doesn't monitor the spare. Sensors are activated by inertial control and the spare doesn't spin. The system sees 4 uniqiue id'd active sensors reporting a pressure.I don't have full access to pull the requirement but a few years back it becam a federal requirement that all us vehicles must now be equipped with TPMS monitoring. So everyone should have it.
And it does monitor the spare at all times. You can search the threads and many people have had TPMs lights on and after hours of trouble shooting with no luck have finally found that it was the spare tire that was low. The TPMS only monitors a sensor freq. it does not know which tire is low or how many tires there actually are.
No worry, your light won't come on because of the spare. Get a sharpie and write "No TPMS - 01/17/13" on the inside of the spare's rim, so a few years from now when you use it you'll know why the dash light comes on.Sorry for bumping an old thread but I was curious about this as well. I just sold my original set of tires off a 2013 JKU last night, and while I had transferred the sensors to my 4 new wheels and tires when I had them changed (I only bought 4 new wheels and tires and kept one of the originals for a spare), I totally forgot about the one that was still in the original spare.
So I sold my spare along with the original set of 4 last night but no lights have lit up on the dash yet.
So I am assuming this must be true, as long as the wheel is not in motion then it is not being monitored by the computer, unless my dash light is suddenly going to come on today.
The Spare isn't part of a Tire Rotation, for one, that's why it's called a spare, to be ready when needed, not worn out/down. Per the owners manual, it shows you how to rotate and the spare will not set off the tire warnings.... A spare is to be used as a spare, not as a permanent solution.Should be in all five or you'd have problems with the TPMS when you do a five tire rotation. I know the 2012s have them in all five.
You are Right....Here is that info from the 2013 Owners manual:While the is a TPMS sensor in the spare the system doesn't monitor the spare. Sensors are activated by inertial control and the spare doesn't spin. The system sees 4 uniqiue id'd active sensors reporting a pressure.
Let the air out of your spare and see what (doesn't) happen.
Most of those people that reported dash lights simply inflated past the threshold turning them off. A cheap tire gauge that reports on the high side will cause this problem.
REad your Manual.....plus thst's the only way these devices can work.....if they were on 24/7 they would have to be changed very often....the Battery can't be that big and last that long....so how else could that work?I don't have full access to pull the requirement but a few years back it becam a federal requirement that all us vehicles must now be equipped with TPMS monitoring. So everyone should have it.
And it does monitor the spare at all times. You can search the threads and many people have had TPMs lights on and after hours of trouble shooting with no luck have finally found that it was the spare tire that was low. The TPMS only monitors a sensor freq. it does not know which tire is low or how many tires there actually are.
A spare on every JKU I have seen is the exact same wheel, tire, and TPMS sensor that's on every corner of your wrangler. As such, it's somewhat of a waste not to rotate it into the mix. (Rubber doesn't last forever). Not to be nit-picky, but if it's rotated in, it tends to be around the same outside diameter when they wear down (so your not putting on a slightly larger spare if the other tires are worn - works the diff more -ok-pretty nit-picky, but accurate nonetheless). Also, a new spare almost says "take me", so I always toss a more worn tire on there.The Spare isn't part of a Tire Rotation, for one, that's why it's called a spare, to be ready when needed, not worn out/down. Per the owners manual, it shows you how to rotate and the spare will not set off the tire warnings.... A spare is to be used as a spare, not as a permanent solution.