understanding low tire pressure light


  #1  
Old 03-21-17, 07:30 AM
M
Forum Topic Moderator
Thread Starter
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,659
Received 835 Upvotes on 732 Posts
understanding low tire pressure light

We have 2 vehicles with the low tire idiot light. My 2010 Jeep calls for 35 psi in the tires and the light comes on when it drops to 33 psi. My wife has a 2016 Nissan Altima which calls for 32 psi. The onboard gauge said the tires had 27 psi but my gauge said 26. I aired them up to 34 psi. The low tire light never came on with her car.

I know there are differences between manufactures but what is the norm?
 
  #2  
Old 03-21-17, 08:49 AM
Marq1's Avatar
Member
Join Date: Sep 2016
Location: USA MI
Posts: 9,745
Received 1,210 Upvotes on 1,098 Posts
Each OEM sets their own requirements but 3-5psi seems to be the norm!
 
  #3  
Old 03-21-17, 01:03 PM
Gunguy45's Avatar
Super Moderator
Join Date: Dec 2007
Location: USA
Posts: 19,281
Received 6 Upvotes on 6 Posts
Ex-'s Kia had the light come on. Checked all to verify. 1 tire down 1.5 psi. Checked with regular and digital gauge...yup, 1.5 psi. Can't be that sensitive, well, still under warranty, but I'll set it to 32 just to see. After 3 min of driving, light went out. 1.5 psi???
 
  #4  
Old 03-21-17, 01:24 PM
M
Forum Topic Moderator
Thread Starter
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,659
Received 835 Upvotes on 732 Posts
I don't have a digital tire gauge but it amazed/aggravated me the first time the low tire light came on in my jeep. It pretty much comes on with the onset of every winter and I've never had less than 33 psi in any of those tires. So a 5-6 psi difference came as a bit of a shock with her Nissan. For some reason 27 - 32 seems like more than that Personally I just as soon not have that feature. Just something more to go wrong or wear out. I've always been able to tell if one front tire was more than a pound or two lower than the other and no more than 5 psi difference for the back tires.
 
  #5  
Old 03-21-17, 02:13 PM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 29,711
Upvotes: 0
Received 15 Upvotes on 13 Posts
Current vehicle is the first with that idiot light. Doesn't even tell you what tire. Got the darn thing two days ago. Going to have to go out and cuss at it soon.
 
  #6  
Old 03-21-17, 02:26 PM
M
Forum Topic Moderator
Thread Starter
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,659
Received 835 Upvotes on 732 Posts
I'm under strict orders not to cuss out my wife's car ..... but then again what mama don't know

My jeep doesn't tell what tire as far as I know but every time it's lit up - all 4 tires were 2 lbs low. It doesn't monitor the spare until it's on the ground.

My wife's car ahs an onboard read out of the tire pressures but I have no idea if it lets you know which one if/when it lights up.
 
  #7  
Old 03-21-17, 04:21 PM
Marq1's Avatar
Member
Join Date: Sep 2016
Location: USA MI
Posts: 9,745
Received 1,210 Upvotes on 1,098 Posts
Current vehicle is the first with that idiot light. Doesn't even tell you what tire.
That is actually a better feature, cant tell you how many stories I hear where someone has rotated the tires, got a signal for a low tire, and the owner keeps putting air in the tire.

Hint, car doesn't know the front tires are now in the back!
 
  #8  
Old 03-22-17, 08:37 AM
B
Member
Join Date: Oct 2008
Posts: 1,215
Upvotes: 0
Received 0 Upvotes on 0 Posts
In my experience, automotive air pressure gauges are the LEAST accurate devices I have ever worked with! One gauge will say 30, another 35. The worst seem to be the gauges attached to the filler hoses at gas stations.

That goes for the internal gauges in tires as well.

It seems to me bicycle tire gauges, purchased from a quality independent bike shop, are much higher quality. I don't know if they are more accurate though?
 
  #9  
Old 03-22-17, 10:50 AM
W
Member
Join Date: Feb 2006
Location: USA
Posts: 6,395
Received 63 Upvotes on 55 Posts
Tire Pressure

My truck displays tire pressure of all four tires by position.

I have found that pressure fluctuates about one pound for each 10 degrees change temperature of ambient air.
 
  #10  
Old 03-22-17, 12:22 PM
F
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 16,321
Received 38 Upvotes on 30 Posts
My 2009 Toyota Camry has a single light to denote low pressure. I currently have a slow leak on the right rear and even when the pressure drops to 26 psi (rated pressure is 34) the light is dark. It DOES work, I have found the pressure to be as low as 16 psi when the light is on.

My sister's kid used to work as a mechanic's helper at a Toyota dealership. He told me the tire pressure monitors were always causing problems. We can all thank the Federal government for the requirement to have the tire pressure monitors.
 
  #11  
Old 03-22-17, 12:59 PM
czizzi's Avatar
Member
Join Date: Jul 2007
Location: USA
Posts: 6,541
Received 15 Upvotes on 13 Posts
The sensor works on an internal battery similar to a watch battery. May be that the battery is dead on the vehicle. It is located on the other side of the fill valve on the inside of the rims and you have to remove tire to get to it. My wife's car has it and it constantly reads "service tire monitor".
 
  #12  
Old 03-23-17, 03:43 AM
M
Forum Topic Moderator
Thread Starter
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 45,659
Received 835 Upvotes on 732 Posts
I doubt the battery would be dead on my wife's car as it only has 1600 miles on it. I'm just surprised that there is such a wide range between the different manufactures.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: