My experience with the pressure system started about a week and a half ago when the cold weather hit. Every morning when I get in truck the indicator stays on, for I'd say 1st 10 miles or so. When the tires warm up, light goes out and doesn't come back on until next morning. Have'nt checked my tires yet, figured it has something to do with the changes in temperature.

a little update on my situation...

i got my tires rotates and had them check the pressure on the spare. he said it was a little low, but not too bad. but he put more air in it. i'll be in the mountains again in a couple of weeks, so i'll let you know if that was the problem.

I have the same crap happening. I've added air to my tires now running 35 psi, and the weather is getting cold so the light came on. Tried to add air to the spare at the gas station but I have sport wheels and the angle won't let me add air. I guess I will go by the dealers and let them add the air, what a POS setup. Is it the air pressure difference or is it the total air pressure that sets of the alarm? Gets cold pressure goes down in the spare the alarm goes off?? Or it gets cold air pressure goes down I add air to the tires on the ground and the air pressure difference between the spare and the tires on the ground causes the alarm to go off??

Anytime my air pressure light came on, it was one of the tires on the ground, not the spare. I run my tires at the recommended pressure that is on the door jamb. Recently, when cold weather hit, one of my front tires was low, causing the light. I have now installed my winter rims with rubber valves, and no light yet, but it came on intermittently last winter.

I'm having a similar issue. Mine is on steady and I attempted to put air in the tires with a weak chevron mart compressor to no avail. I'm going to try again and I hope it isn't a chronic nusiance.

To chime in here and keep this thread active, I have just installed aftermarket wheels and tires with regular, rubber valves. No TPMS light for a week and then it started flashing. I topped up the spare but the light is still flashing. My wife says it drives her crazy. I don't even notice it. Maybe I'll put a piece of tape over the lens.

If anyone figures out how this thing works, let me know.

Is the TPM sensor mounted on the tire or on the rim itself? I want to know if I replace my tires will I need to transfer the sensors to the new set.

The idea here is to find the connector to the sensor, disconnect it, and somehow determine the resistance of the sensor on the connector terminals when no MIL.

Then on the input of the ECU side of the connector, you connect a resistor that equates to an "in range" load value that the sensor would put out under nominal conditions.

We do this on the VSV (vacuum switching valve) connectors on the Supra when we go to a aftermarket turbo set-up. This so we don't get a "check engine" MIL. The "check engine " light will respond to all other conditions so it's much preferred over just removing the lamp bulb or using tape.

Put simply we need to place the correct resistor across the connector terminals going to the ECU and stow the sensor connector. Just to fake out the computer and give it an in range value. Of course this means the sensors wont tell us if our tires are low, but I can usually catch that



Just a thought...

Well, it finally happened to me as well... I had the truck parked at a friends house for a few hours, it was pretty cold...40 degrees or so. When I got in and drove, the light came on. I didn't think much of it...the next day light was still on as I drove it to a mall. When I came out and got in, light was out..it was warmer at this point. Haven't seen the light since.

I know this light isn't a real big deal...but it's kinda annoying being these are new vehicles we are talking about.

Mine was the spare. Had to lower it to fill it. Set all of your tires to 35 psi including your spare and that should cover you even during below "0" weather. Your tire pressure will go down 1 psi for every 10 degree drop in temp. The light will come on when they get below 28 psi's.

PS- I find that 35 psi is a good setting for ride quality and tire wear.

Mine went away when I put air in the tires. Yay!

I think the people with the blinking MIL have the real issue.

New to the forum, although been reading for couple months now. This morning it was 14' outside and with 2300-miles I was surprised to find the dash light indicating tire pressure should be my concern for the day.

Called the dealer, the service manager wasn't much help. I've learned about this problem reading this thread! I checked all 4 tires and the spare - all at 31-lbs. This was done after I got home, so I'll check again in a couple hours for a cold reading.

It's a Monday, next available appointment is a week away. I'll play with the 35-lb someone else mentioned. Does the senser reset automatically? Or is there some secret reset trick?

Really like the 4Runner, but I too have couple of the nagging issues I've read about. The driver seat - making noise. I also have a noise when the sunroof is fully opened, sounds as if the sunroof motor cycles on and off. Gave the dealership a chance to resolve, they couldn't duplicate. I'll wait until it starts to get warmer, shouldn't need much open air with it being 14'.

Put my T4R.ORG sticker on the other day. Anyone else out there from Delaware?

Hey welcome to forum. Hope we can help with your questions.

I've had the truck long enough to know that when the temp drops it wreaks havoc with the TPM. Tires seem to be low on air when it gets really cold tricking the TPM. After driving for a while, the air in the tires should warm up and sensor should go off. If it doesn't go off, usually the spare is the culprit. Since its not a drive wheel it isn't warming up. The last couple of days has been pretty cold in VA so I've seen the same effect as you.

The sunroof motor cycling on/off could be the automatic feature of the wind deflector. The wind deflector will lower when you exceed a speed of about 55mph and then it will raise again when you drop below 45mph. If its not that then there is something wierd going on with your sunroof.

Delaware here. I've seen a few around here from Delaware. Nice to know our small state is representing.

Oddly, as soon as the temperature outside came up, today it was @ 40' - dash indicator light went out on it's own.

(I didn't get around to putting the tires at 35-lbs the night before.)