Tire pressure light comes on, goes off

When was the last time you reset the TPMS? Try that.

 

Do you have your license plate bulbs replaced with LED's?
I had the same issue and it turned out to be the LED's that were interfering with the TPMS reciever which is located near the rear of the vehicle. The ONLY LED's that caused this problem were the high power SMD ones. I got some different LED's and it works just fine.

 

I honestly don't think they would interfere with the TPMS receiver. When the light flashes, and then stays on - it means there is a malfunction in the tire pressure monitoring system. If it just comes on without flashing, that means you are actually losing pressure. This is in your manual if you'd like to confirm. Maybe you have a fault with the system, but I doubt it. I say if this happens again be sure to post and let us know. I've never had this issue - only when I had the LED's in the license plate area.

 

Check all 4 tires and then set the tpms. If it goes off again see dealer.

 

Is your light still on, flashing for a minute after you start the car?

If your light flashes a minute, then stays on, this indicates some type of system problem. It the light simply comes on, this indicates a tire-pressure problem.

If your light is on, you can determine the problem if you're brave, by shorting TC and CG on the DLC3 connector, with your car on, but engine off (press "on" twice without pressing the brake). The TPMS light will sequentially flash the DTCs stored in the TPWS ECU, and then you'll know what's wrong.

Here are the codes:

http://www-rohan.sdsu.edu/~nash/TCH/TPMS.pdf

 

I think you just solved a mystery regarding my Prius... I was about to post a question about it.
A year or so after I bought my '06 Prius, I got 4 wheels for a set of X-Ice for the winter. Work great, but with those wheels/rims on, every time I drive past a certain spot on the interstate some 60 miles from here, the tire pressure light comes on. Stays on for the rest of the day, then eventually goes off and stays off until I happen to drive past that spot again.
At first I checked the tires, but eventually I knew they were fine and there was something special about that spot. The road, the elevation, something. Now it seems pretty clear that there is probably some type of interference right there that make the light come on when I'm using those wheels, which are not Toyota rims.
Anyone else experience this?

 

That location is 15 minutes from your home, right? At 15 minutes, the TPMS light will go on, if any of the TPMS sensors' signals has not been received (ie. you drive away from the tires, with sensors, that are in your garage).

 

Seems unlikely at 15 minutes, since the poster said it was about 60 miles, unless they got that pursuit mode from KITT in Knight Rider .

It seems odd that the one particular spot seems to cause it, then cancel it though. Even if there was some sort of interference (something using a similar frequency), I would expect it to clear before driving past it again.

 

My bad. I didn't read the post closely. Clearly, he is passing a TPMS check-point!

 

No-- way more than 15 minutes. Takes almost that long to get from my house to the freeway. Plus it doesn't do it any other time or place, even if I'm on the road for a hour.

But one thing I got to thinking about was that I found this thread doing a search, and hadn't noticed it was in the 2010+ models area, so I'm not positive my 06 has the RF sensor system. It may have the type that compares the rotations of the wheels to determine if one is "fuller" than the other (-if I'm remembering that right)...

 

Hey kid, go play in your own forum.

No seriously, that could be the case. My 2002 Sienna has that system. The way to check is to look at your valve stems. If they're rubber, they aren't the TPMS-type.