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Discussion Starter #1
Please see the last couple of sentences for the those that prefer to TL;DR. :amuse:

So I'm not sure how or when this happened but I've only had to fill air in my tires once in the last 11 months. The TPMS readings were fairly consistent through the months.

It was actually pretty dangerous because I was filling air in a vehicle's tires for the very first time in my life and I didn't know how much is too much. I relied on the RF and LF TPMS values in the DIC (the brass stick "sensor" on the air hose was very loose and I wasn't sure how accurate it'd be) and no matter how much air I tried to get in there (front right), the values simply wouldn't change. I eventually stopped when I could actually SEE the tire expand a little more than what I intuitively thought was natural. I thought I'd wait coz the TPMS might be slow to respond or something. The gf was at the wheel giving me a verbal readout of the numbers. I went to the back and started getting air in those. She then switched the DIC to RR and LR and said "Uh, it says the pressure is 46 for RR". My tire max is rated at 44. I kinda got scared because we were in the middle on nowhere and a tire blowout (while not as dangerous as it happening when driving) would be a big pain to fix.

So I let air out of the rear tire. I kept going and the numbers wouldn't change on the RR. I began to panic for a bit but then it kinda struck me. I told the gf to monitor the RR number on the DIC and I went to the RF tire and started letting the air out. Sure enough, the RR number immediately dropped. I then quickly got all tires up to 34 and was on my way. I think I had 46 psi in the tire for only about half a minute or so and it has since been four months and nothing's happened so I suppose the tire is fine.

What I'm wondering is (and for those that came down here without reading my interesting story :embarrest: as the title says)why would this happen, and more importantly, is there a way for me to fix this without having to go to the dealership?

Thank you.
 

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Yes, wheels were rotated without relearning the sensors. This is easily calibrated you can do it yourself, or since it's been over 4 months you could just rotate your tires front to back again.

---------- Post added at 09:46 PM ---------- Previous post was at 08:10 PM ----------

TPMS Matching Process for Vehicles with Remote Keyless Entry (RKE)
Set the parking brake.
Turn the ignition switch to ON/RUN with the engine off.
Press and hold the Remote Keyless Entry (RKE) transmitter's lock and unlock buttons, at the same time, for about five seconds to start the TPMS learn mode. The horn sounds twice indicating the TPMS receiver is ready and in learn mode.
Start with the driver side front tire. The driver side front turn signal also comes on to indicate that corner's sensor is ready to be learned.
Remove the valve cap from the tire's valve stem. Activate the TPMS sensor by increasing or decreasing the tire's air pressure for about eight seconds. The horn chirp, can take up to 30 seconds to sound. It chirps one time and then all the turn signals flash one time to confirm the sensor identification code has been matched to the tire/wheel position.
The passenger side front turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the passenger side front tire and repeat the procedure in Step 5.
The passenger side rear turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the passenger side rear tire and repeat the procedure in Step 5.
The driver side rear turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the driver side rear tire, and repeat the procedure in Step 5.
After hearing the single horn chirp for the driver side rear tire, two additional horn chirps sound to indicate the tire learning process is done. Turn the ignition switch to LOCK/OFF.
If no tires are learned after entering the TPMS learn mode, or if communication with the receiver stops, or if the time limit has expired, turn the ignition switch to LOCK/OFF and start over beginning with Step 2.

Set all four tires to the recommended air pressure level as indicated on the Tire and Loading Information label.
Put the valve caps back on the valve stems.

---------- Post added at 09:48 PM ---------- Previous post was at 09:46 PM ----------

TPMS Matching Process for Vehicles without Remote Keyless Entry (RKE)
Set the parking brake.
Turn the ignition switch to ON/RUN with the engine off.
Using the Driver Information Center (DIC), press the INFO and Set/Reset buttons at the same time for about one second. Then press and release the INFO button until the TIRE LEARN? message displays.
Press and hold the Set/Reset DIC button for approximately three seconds to start the TPMS learn mode. The horn sounds twice to indicate the TPMS receiver is ready and the TIRE LEARN ON message displays. The driver side front turn signal also comes on to indicate that corner sensor is ready to be learned.
Start with the driver side front tire.
Remove the valve cap from the tire's valve stem. Activate the TPMS sensor by increasing or decreasing the tire's air pressure for about eight seconds. The horn chirp, can take up to 30 seconds to sound. It chirps one time and then all the turn signals flash one time to confirm the sensor identification code has been matched to the tire/wheel position.
The passenger side front turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the passenger side front tire and repeat the procedure in Step 6.
The passenger side rear turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the passenger side rear tire and repeat the procedure in Step 6.
The driver side rear turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the driver side rear tire, and repeat the procedure in Step 6.
After hearing the single horn chirp for the driver side rear tire, two additional horn chirps sound to indicate the tire learning process is done. The LEARN COMPLETE message displays if all four tire positions are learned. Turn the ignition switch to LOCK/OFF.
If no tires are learned after entering the TPMS learn mode, or if communication with the receiver stops, or if the time limit has expired, the TIRE LEARN? message displays on the DIC. Turn the ignition switch to LOCK/OFF and start over beginning with Step 2.

Set all four tires to the recommended air pressure level as indicated on the Tire and Loading Information label.
Put the valve caps back on the valve stems.
 

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Discussion Starter #4
Hey thanks a lot Coby. I actually read about the re-learn feature, both on posts and in the manual but none of the posts said that this was needed after every rotation. But it makes sense since the sensors probably have an RFID that are calibrated to correspond to a particular wheel and when it is rotated, it still thinks it is on that wheel unless it is recalibrated.

Thanks again. I will calibrate them later this evening and give an update here.
 

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When I saw how the tire shop treated my wheels when rotating tires "for free" I was quick to order the TPMS tool myself. It's like 80 bucks and since I have 3 sets of wheels (summer, winter and track) it is priceless to be able to do the relearn myself after a swap or rotate in the comfort of my own garage :)
 

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Where did you get one for $80?
 

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The tool when pointed at the valve stem will transmit a signal to the RCDLR instead of you manually inflating and deflating the tire to calibrate it to the right position on the car.
 

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