Low tire pressure light...

[FRSBRZGT86FAN]

Originally Posted by AKUSHOU

After driving 20+ miles to work with an average speed of 60-65 mph and the light not going out I was scratching my head. But that same trip back home in the afternoon it went out sometime along the way.

So figuring it was temp related, but wanted to make sure with you fine folks

Originally Posted by PandaSPUR

Yep, I think the approximation is like every 10 degrees = 1psi. Rough approximation.

Btw, related but slightly OT, does anyone know if the TPMS actually updates during the ride? Or does it only update on engine start? To me, it seems like it only checks pressure on engine start. I don't think I've ever had that light go out mid-drive.

Anyway, I just picked up a Vivair portable compressor that runs off the 12v accessory port and a digital tire gauge. Cost me $50 after tax from Amazon.

My 2015 nissan rogue with tech package fully loaded seems to have the whole temp thing figured out. In fact it won't even show each of the tire pressures till you've driven for some time and the tires get up to a preset temp, or if one of the sensors is reading an extremely low number. I feel like the TPMS system on these cars could use an update as a whole.

[Tcoat]

Originally Posted by PandaSPUR

Yep, I think the approximation is like every 10 degrees = 1psi. Rough approximation.

Btw, related but slightly OT, does anyone know if the TPMS actually updates during the ride? Or does it only update on engine start? To me, it seems like it only checks pressure on engine start. I don't think I've ever had that light go out mid-drive.

Anyway, I just picked up a Vivair portable compressor that runs off the 12v accessory port and a digital tire gauge. Cost me $50 after tax from Amazon.

They are updating constantly. Not much use having a low pressure sensor that only tells if there is a problem with the pressure at start up.

[Tcoat]

Originally Posted by FRSBRZGT86FAN

My 2015 nissan rogue with tech package fully loaded seems to have the whole temp thing figured out. In fact it won't even show each of the tire pressures till you've driven for some time and the tires get up to a preset temp, or if one of the sensors is reading an extremely low number. I feel like the TPMS system on these cars could use an update as a whole.

So you could drive with an almost flat tire until it reaches a certain temp? Or if it is below a certain threshold it would still tell you it is low regardless of temperature? That sounds overly complex to me. Just let me know if low. I know if it is cold out and will make the call if it needs to be checked or not.

[jawn]

My last car used the wheel speed sensors to figure out if one of the tires was flat. No TPMS needed on the wheel itself. I miss it.

[mdm]

Originally Posted by jawn

My last car used the wheel speed sensors to figure out if one of the tires was flat. No TPMS needed on the wheel itself. I miss it.

I don't have TPMS but another version of my car has this speed-based pseudo-TPMS. In the manual, they are saying that in some cases such system may miss a low-pressure tire, like two tires on one side or on the same axle losing pressure. They go on to say that these cases account for ~50% of real-life low-tire-pressure situations. So it seems that true TPMS is better after all :-)

[FRSBRZGT86FAN]

Originally Posted by Tcoat

So you could drive with an almost flat tire until it reaches a certain temp? Or if it is below a certain threshold it would still tell you it is low regardless of temperature? That sounds overly complex to me. Just let me know if low. I know if it is cold out and will make the call if it needs to be checked or not.

No the tpms works normally, but when you switch to the infotainment screen which tells you exact pressures it won't show it, it shows a message like "Tire Pressures will appear while driving". One morning we had a flat when you started the car it would say Warning _____ side ____ tire leak detected and it also prevents the awd from being fully engaged when that occurs. So yes below a certain threshold it will warn you regardless, theres a lot of safety tech in that car.

[PandaSPUR]

Originally Posted by Tcoat

They are updating constantly. Not much use having a low pressure sensor that only tells if there is a problem with the pressure at start up.

Makes sense. Coulda sworn I've had the light stay on until I park the car momentarily and then restart it. Guess I'm imagining it.

Anyway, will be inflating my tires some more once my pump and gauge get here tomorrow. wee.

[chaoskaze]

isn't every -10 degree sorta = -1 psi?

[Tcoat]

Originally Posted by FRSBRZGT86FAN

No the tpms works normally, but when you switch to the infotainment screen which tells you exact pressures it won't show it, it shows a message like "Tire Pressures will appear while driving". One morning we had a flat when you started the car it would say Warning _____ side ____ tire leak detected and it also prevents the awd from being fully engaged when that occurs. So yes below a certain threshold it will warn you regardless, theres a lot of safety tech in that car.

OK that makes sense. Still over complicated but makes sense.

[bcj]

The warning will come on if you get a hole in the tire while driving.
Got a .75" x 1.25" piece of metal strapping in a rear tire. Sucked.

Inspect your tires for foreign materials in the tread.

If you let your pressures drop close enough to the low margin, a high pressure weather system cruising through may trigger on the inside/outside differential pressure.
Man up and put some air in your tires. Running low isn't good for them.

[Dorb]

My BRZ has sat in the garage pretty much since winter snow hit, just fired it up and the tire light was on, just put air in as they were down to 27-29psi each tire. I was amazed. My Avalanche sits out all year and checking it tomorrow after work, can't wait to see how low it will be. - I just don't recall the BRZ losing that much the last couple of winters.

[BRZnut]

Originally Posted by Dorb

My BRZ has sat in the garage pretty much since winter snow hit, just fired it up and the tire light was on, just put air in as they were down to 27-29psi each tire. I was amazed. My Avalanche sits out all year and checking it tomorrow after work, can't wait to see how low it will be. - I just don't recall the BRZ losing that much the last couple of winters.

Mine does that each winter if I do not keep on top of it and triggers the low pressure light at around the same level as you.

[SmartedPanda]

Happens to mein California, 40F-ish and 1 tire loses 2-3 PSI.

[thomasmryan]

coming from motorcycles, I check the tire pressure every ride.


if your garage is 60 and its 20 outside, +4 psi.