Tire pressure warning system (false low pressure readings)

[lyronva]

We have a 2005 G35 Coupe, and for the last 6 months or so there has been a very slow leak in the right rear that is manageable. If I don't check the pressure every 2 or 3 weeks, it can drop low enough that the indicator light comes on. When this occurs, the low tire is around 30 psi (where we're inflating to 35 psi cold, as recommended).

For the last couple of weeks, Just a few days after a full check for all 4 tires' pressure, the indicator light will illuminate. I was initially thinking that the leak had accelerated (or we had run over something and punctured one of them), but a check indicates that all is well. The light will go off for a day or so and then come back on.

Has anyone seen this phenomenon? Is there a simple reset procedure? The manual suggests a reset at the dealer in the event of having to use the spare, but that's all they provide.

Thanks very much in advance for any help you all can provide -

B

[BusyBadger]

What's the outside temp when the light is on and then goes off?

I've had it get cold enough outside that my indiactor light comes on when I'm at altitude and then when I get to a lower and warmer level the psi will rise and the light will go out when everything is "back to normal".

[lyronva]

What's the outside temp when the light is on and then goes off?

I've had it get cold enough outside that my indiactor light comes on when I'm at altitude and then when I get to a lower and warmer level the psi will rise and the light will go out when everything is "back to normal".

No, but this is a very good consideration. While we do drive at altitude and/or in cold temperatures sometimes, these latest episodes have been at sea level and where the lowest of the 4 room temp tire pressures is about 33 psi, and it hasn't gotten any colder than maybe 45F here, which wouldn't be enough to drop it below 30 psi (or wherever the indicator point is). Furthermore, sometimes the light is on after driving a long ways when the tires are hot and reading 38-39 psi when they read 35 cold.

Thanks -

B

[telcoman]

We have a 2005 G35 Coupe, and for the last 6 months or so there has been a very slow leak in the right rear that is manageable. If I don't check the pressure every 2 or 3 weeks, it can drop low enough that the indicator light comes on. When this occurs, the low tire is around 30 psi (where we're inflating to 35 psi cold, as recommended).

For the last couple of weeks, Just a few days after a full check for all 4 tires' pressure, the indicator light will illuminate. I was initially thinking that the leak had accelerated (or we had run over something and punctured one of them), but a check indicates that all is well. The light will go off for a day or so and then come back on.

Has anyone seen this phenomenon? Is there a simple reset procedure? The manual suggests a reset at the dealer in the event of having to use the spare, but that's all they provide.

Thanks very much in advance for any help you all can provide -

B

Why not just get the tire inspected and repaired?

I too had a slow leak in one tire and had it repaired. Turned out a large staple had just made it into the center of the tire.

Good tires and brakes can prevent you having an accident.

If the tire is going to fail it will happen on a dark and stormy night when you are tired, in a rush to just get home and go to sleep.
Or if you are single the tire will fail when on a first date with a hottie who just suggested her place and by the time you get the tire situation straightened out she'll have a headache.

Telcoman

[SVTCOBRA]

Do you encounter bumpy roads??
I think I have a sensor going bad in my coupe.
A bumpy road will set one of the off. '
Also, have noticed that over the winter the sedan lights do not come on. It has Nitrogen.
The coupe lights will come on as temps drop. No Nitrogen.
Also, the sedan tires do not loose air as the coupe does.
Not that the coupe looses a lot! but, I went 1 year without putting any air in the sedan, which is unusual for me and I check the tires frequently.

[mgrgata]

I too have the same issue. When the light turned on, I went straight for a gas station and checked my tires and pressure was well above the warning light as prescribed in the manual. My opinion I think its a bad sensor and I drive on rough roads. I did have the alarm go off when my 19' tires were below 28 psi. At least it works when it is supposed to.

[lyronva]

I too have the same issue. When the light turned on, I went straight for a gas station and checked my tires and pressure was well above the warning light as prescribed in the manual. My opinion I think its a bad sensor and I drive on rough roads. I did have the alarm go off when my 19' tires were below 28 psi. At least it works when it is supposed to.

Thanks, it's good to know that someone else has experienced this phenomenon (and I don't mean that the way it sounds). I'm assuming there are 4 individual sensors? And yes, if it's going to be dodgy, it's good that it's false positives rather than lack of negatives).

B

[infinitgkid]

If the tire is going to fail it will happen on a dark and stormy night when you are tired, in a rush to just get home and go to sleep.
Or if you are single the tire will fail when on a first date with a hottie who just suggested her place and by the time you get the tire situation straightened out she'll have a headache.

Telcoman

A little over dramatic, but a good point none-the-less. As I'm sure you can imagine, having a tire fail on you is always an inconvenience.

Fix the tire and set your tire pressure to your desired level.

For me, I have my tires set to 30 psi on all four corners. It used to be 35, but If you lower your pressure on all four tires so that the tires read the same across the board, the computer should be able to adapt. Also, another thing to consider is that the indicator goes off at the slightest margin of difference in pressures; whether it increases or decreases.

For example, just the other day my tire pressure is set at 30 psi all around and my driver side front dropped to 29.7 (Digital tire pressure gauges are SOOOOOOO accurate/awesome!) and the light came on.

But if anything, I think your REAL issue here is just getting that tire fixed. Slow leak or big leak; a leak is a leak and is bad news.

[tfree32]

I had a sensor go off over the weekend. The tires are fine and it appears that the cold weather caused it.

[lyronva]

If the tire is going to fail it will happen on a dark and stormy night when you are tired, in a rush to just get home and go to sleep.
Or if you are single the tire will fail when on a first date with a hottie who just suggested her place and by the time you get the tire situation straightened out she'll have a headache.

Telcoman

A little over dramatic, but a good point none-the-less. As I'm sure you can imagine, having a tire fail on you is always an inconvenience.

Fix the tire and set your tire pressure to your desired level.

For me, I have my tires set to 30 psi on all four corners. It used to be 35, but If you lower your pressure on all four tires so that the tires read the same across the board, the computer should be able to adapt. Also, another thing to consider is that the indicator goes off at the slightest margin of difference in pressures; whether it increases or decreases.

For example, just the other day my tire pressure is set at 30 psi all around and my driver side front dropped to 29.7 (Digital tire pressure gauges are SOOOOOOO accurate/awesome!) and the light came on.

But if anything, I think your REAL issue here is just getting that tire fixed. Slow leak or big leak; a leak is a leak and is bad news.

> But if anything, I think your REAL issue here is just getting that tire fixed. Slow leak or big leak; a leak is a leak and is bad news.

Quite true -

> Fix the tire and set your tire pressure to your desired level.

I am still thinking that this will not solve the problem - there are instances where the sensor goes off and all 4 tires are reading within 0.5 psi (no telling margin of error is, but the resolution of the gauge is only to +/- 0.5 psi).

> If you lower your pressure on all four tires so that the tires read the same across the board, the computer should be able to adapt.

> Also, another thing to consider is that the indicator goes off at the slightest margin of difference in pressures; whether it increases or decreases.

Both interesting points if true - I will have to test these sometime -

Thanks -

B

[gwoods]

My tpms light is on and all my tires including spare are at 35 psi. Dealership says that the sensors do wear out and wants $250 to replace whichever one is worn. I am just ignoring the light and checking my tire pressure about once a month like I always do anyway.

[telcoman]

My tpms light is on and all my tires including spare are at 35 psi. Dealership says that the sensors do wear out and wants $250 to replace whichever one is worn. I am just ignoring the light and checking my tire pressure about once a month like I always do anyway.

I had two sensors replaced while under warranty

I have my pressure set at 35lbs on all four tires when cold

[jerbru]

has anyone found a solution for the false tire pressure light?

[telcoman]

has anyone found a solution for the false tire pressure light?

Yes



Replace the defective sensor

They have a battery in them. Like the ipod the batteries are non replacable and do wear out. The sensors are about $125 and a half hour labor to replace them. They have to be paired to the ECU in your vehicle. Better to let the dealer do it in my opinion

Telcoman