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My tire pressure warning light came on a couple of days ago. I checked the tires and the two fronts were low (24 and 25 psi). I filled each to 29psi as the manual recommends, but the warning light has stayed on (3 days now). Is there a reset switch for this? Any recommedations?

Thx.
 

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There is a button below the radio that resets the light. It should have a picture on it that looks like the TPMS light. I have found that most cheap tire pressure gauges are not too accurate. I ended up getting a digital gauge. Tires will loose some air over time and temperature will change the pressure too.
 

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Interestiigly mine did the same thing (also because of the cold weather - that's not so interesting) as all were low, but upon bringing all 4 tires up to specs and starting the car, the TPMS light reset itself - I didn't need to hit the reset switch!! :confused:
 

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I think that the reset of the system tells it to expect a certain value from a specific sensor. This is not an absolute value. Hence you can tune the behavior of the suspension without violating the system parameters.
 

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When I hit a pothole, the TPMS light will come on sometimes. Resetting the light doesn't last too long nor does shutting off the car and restarting. If I mess with the tire pressure, let out some air and refill all 4 tires, I can reset the light and it stays off.

I know, go around the potholes... but sometimes I am looking at other cars or that cute girl walking down the street....
 

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How low does the pressure have to get before the light goes on all the time???? My light goes on 2-3 times a day. today it was on most of the trip to work and back. Resetting the light works for about 10 min. pressure is about 1/2 lb low when I could finally check it, I'm ready to add 5 lbs to each tire or tape over the light. it is annoying especially at night.

And I gave the cute girl a ride in my Smart. Sha ordered one the next day.
 

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I think that resetting the TPMS system only sets the new level to monitor.
here is part of the Tech manual that has been discussed here. do not know what a relevant loss would be?

A previously stored tire pressure is used as a comparative value. If a relevant loss of pressure occurs, the tire pressure monitor warning lamp in the instrument cluster warns the driver. The tire pressure measuring range is p = 0 to 78 psi (p = 0 to 5.5 bar).​

Manual restart​
The tire pressure to be monitored can be reset via the
switch on the cockpit switch panel. When the switch is pressed, the current tire pressure is stored in the memory of the control unit and is then used as the reference pressure, as long as it is within the permissible limits.
The tire pressure monitor warning lamp in the instrument cluster flashes to indicate that a manual restart​
has taken place.
 

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Post 15 confirms post 10.

Perhaps it is worth noting that the reset should ONLY be used if you have separately confirmed that all four tires are at the desired pressure. If you reset merely to make the light go away, and the four tires are (as an example) 30,30,30 and 20; then the warning may not signal a low tire till the 20 tire falls even lower. This is because the reset stored 30,30, 30 and 20 as the target values. This would effectively defeat the warning system---in a car with no spare. :)
 

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But what else are you to do if your tires are correctly inflated but the light keeps coming on? I pump mine up using a manual bicycle pump with built-in gauge to exactly the factory pressure when the tires are cold, around 45 degrees, which is cold here in Tucson. But still the light comes on after a minute or so. Now it won't re-set.

As I have said before, this system is not ready for prime time! What would happen if I just took the sensors out of the tires and threw them away? Would I be able to get the light to go out and (more importantly) stay out? This is a city car so who cares if I get a flat, that's what AAA is for.....
 

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Just how positive are you . . .

But what else are you to do if your tires are correctly inflated but the light keeps coming on? I pump mine up using a manual bicycle pump with built-in gauge to exactly the factory pressure when the tires are cold, around 45 degrees,
Just how positive are you that the pump's built-in gauge is anywhere near correct? I had one a few years back for my mower. When I pumped to the same amount in each tire and then checked with a large dial gauge, the tires often varied by several pounds. Worth the $$$ to invest in a really decent gauge for checking the smartie's tires.

Just my $.02 worth. . . :)
 

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... I pump mine up using a manual bicycle pump with built-in gauge to exactly ...
I did use the emergency kit compressor to add some air (easier than the bike pump, and allowed me to check if it's still working), but didn't trust its built-in gauge. Got a brass gauge at Sears (±$6) and if both gauges show about the same, the chance of some accuracy is pretty high... at least enough for me :wink:
 

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No sensors

As I have said before, this system is not ready for prime time! What would happen if I just took the sensors out of the tires and threw them away? Would I be able to get the light to go out and (more importantly) stay out? This is a city car so who cares if I get a flat, that's what AAA is for.....[/quote]

If you take the sensors out, the warning light will flash for a minute when you start the car and then stay on. (I didn't put sensors in my snow tires and that's what mine does. BTW, it doesn't bother me in the least so it might be a solution you'd like.)
 
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