On stock (2012-?) Wranglers, do all wheels including the spare have TPM sensors?

 

Yes. But the spare is not read until it is put into service. Only the active wheels are sensed.

 

Thanks for the quick reply. What makes a wheel "active"? Is it just spinning motion?

I know on GM cars you have to program/activate the TPM sensor to each corner, that's the only way they will be recognized.

 

Yes. Centrifugal force. The computer will find them and they are not specific to any position meaning you can rotate them without programming.

There is an algorithm that causes the computer to probe a particular wheel (or all wheels...I'm not sure on that). The conditions must be met first. That is why it takes different amounts of time for different Jeeps with regards to how long it takes for their new sensors to be recognized. It's quite elaborate and I wish I had bookmarked it when I saw it because I cannot find it again. The sensors in the wheels have batteries which are rated for approximately 7 years of service. However, to make them last longer, the sensors must be rotating to make the connection to the battery. So by disconnecting when parked, battery life is extended.

 

Awesome, thanks guys. I need to pull the wheels off the Jeep and go get them balanced and the TPM question was nagging me, if I had been running with only 4 sensors on a 5 tire rotation. Good to know they've all got 'em

 

TPMS is waste of technology. I can check my own PSI, it will go off if you air down and you will see that annoying TPMS light on the dash. First week I had my new Jeep I took my stock steel wheels off put new wheels and tires on them and Just turned off TPMS using AEV ProCal and never looked back.

 

Then they weren't thinking of you when they mandated these on new vehicles, but most people either choose not to or maybe don't know enough to understand why they need to keep their tires properly inflated on the road. I don't think a day goes by that I don't see at least one car driving at a high rate of speed (speed limit is 70-75 on these roads out here) with noticeable low aired tires. Look at vehicles in the queue at Costco where it is free and easy to have them check and air you up and you will find people with one tire so low the rim is damaging the bead and tire against the ground. Sometimes even when you tell someone they ignore you and get back on the highway like that, puts everyone in danger.

 

I disabled TPMS through my Aeroforce.

 

I just got an idiot light warning that my TPMS is 'malfunctioning' according to the owner's manual. The light flashes for about a minute, then stays on. Dealer said it is probably a battery in one of the sensors. Sucks. Going to see about disabling the whole system.

 

Doubt it's a battery as they are rated for seven years of active time. They are only active when the vehicle is in motion. They use centrifugal force to connect the battery in the sensor. Not sure if it would work but I would try disconnecting the battery negative for 10 minutes to clear the system and then see if it comes back. Otherwise I would disable it rather than putting money into repairing it.