Air pressure light

[Lyonsmin]

We have a 2012 outback and drove it .first time in deep unplowed snow. Performed well but low tire pressure light came on. Checked pressure in all tires,fine. Heard that I should run HIGHER pressure in winter. Any thoughts

[arthuruscg]

The light will also come on if the pressure is to high.

[subiesailor]

Cold temps and being close to the threshold regarding pressure. The sensors in the wheels do not measure pressure they simply trigger a signal when it goes below a certain pressure.

I have not seen them trigger for high pressure and highly doubt they will.

During the winter is when most people experience their first tire dash light when tires which are getting a little soft ie have not been checked see very cold temps and the pressure drops just enough to trip the monitor light.

All you need to do is make sure your running the listed tire pressure on the door on a cold day or morning and your fine.

[jogosub]

Originally Posted by Lyonsmin

We have a 2012 outback and drove it .first time in deep unplowed snow. Performed well but low tire pressure light came on. Checked pressure in all tires,fine. Heard that I should run HIGHER pressure in winter. Any thoughts

You get slightly better traction with higher pressure on ice - but - fresh snow is like sand - you get better results in sand with under-inflated tires. Look at those cars and their tires running Baja 500 races...

[Se7enLC]

Originally Posted by subiesailor

Cold temps and being close to the threshold regarding pressure. The sensors in the wheels do not measure pressure they simply trigger a signal when it goes below a certain pressure.

Not quite true. The sensor itself DOES report a specific pressure for each tire. The car just doesn't do anything with that information apart from reporting when it's too high or low. Same end result, though - you won't get any feedback unless the pressure is too high or too low.

In my last car, you would also get a warning if any one tire were different from the others by more than some threshold, even if all 4 tires were still within the acceptable pressure range. It's probably the same in the Subaru, so it's worth checking to make sure all the tires are at the same pressure.

[H61]

Make sure you check pressure when the tires are stone cold. After the car sits overnight is the best time to get a reading. If you're checking when they are warm or recently driven on they will read high.

[plain OM]

Originally Posted by H61

Make sure you check pressure when the tires are stone cold. After the car sits overnight is the best time to get a reading. If you're checking when they are warm or recently driven on they will read high.

And, if the car is kept in a warm garage but is used in much colder temperatures during the day, then add 1 psi for each 10 degrees drop in temp. (Tire pressure will drop 1 psi for every 10 degrees F in temperature.)

[GLwagon]

Originally Posted by jogosub

You get slightly better traction with higher pressure on ice - but - fresh snow is like sand - you get better results in sand with under-inflated tires. Look at those cars and their tires running Baja 500 races...

Close but wrong,
Sand has no base & you will sink to China.
Floating on snow is possible, but if there is a solid base (like a road) & you are not in too deep of snow you would rather cut through as much as possible at speed.

If you are on a possible surface that you can get buried in (super deep snow) then yes, floating is an option if you never stop moving.

For the average on-road driver in adverse conditions skinny tires & aggressive tread is very nice. The density of the snow will also factor quite a lot also.

Where there is snow there is likely ice, I'll personally take the skinny tires.

[Dirt1St]

I had the same issue with my 2013 OB. TPMS light came on when the temperatures started to drop here in the Denver area, I checked with the dealer, they said that Subaru recommends setting pressure on all 4 tires to 35 or 36 psi (cold). "Cold" here in November is colder than "cold" in August. The cooler temperatures, especially at night caused the pressure to drop just enough to trigger the TPMS warning. I had also be using a 2 psi difference between the front and rear tires. This difference might also have triggered the pressure warning. I generally check my tire pressures first thing in the morning.

[Adrien38]

In Subaru 2012 TPMS sensor that you can run with or without for winter driving. If you choose to run without the TPMS sensors, you'll see a warning light but there are no efficient problems associated with the light.