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Discussion Starter #1
Hello!

I took a speed bump a little took quickly (a tad over 15mph, but that was a very steep speed bump), and since then, the tire pressure light on the dashboard of my Smart ForTwo Passion has been on. I checked the tires' pressure at the gas station... they are all fine.

Should I be worried that the speed bump caused more damage to the car (busted shocks? some damage to the wheels?)? Or would the mechanic be able to just reset the dashboards lights?

Thanks
 

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The dealer would be extra happy to take your money to do it. However, in the manual for your vehicle it tells you how to reset the light.
 

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Discussion Starter #3
Thank you. Would somebody mind giving me the directions as to how to reset the light? I bought my car used, and I wasn't given a copy of the vehicle manual...
 

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If it doesn't stay out after resetting, and making sure your tire pressure is correct, you may have a damaged pressure sensor. I've been there.
 

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Discussion Starter #7
thanks a lot, folks. I'm out of town until the 1st. Then, I'll try resetting the light and I'll see where that gets me.
 

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Discussion Starter #8
I tried resetting the light. It goes off for a little while, but then it lights up again maybe a half hour later.

Any clues what this could mean?

I'm approaching 60k miles, so I need to bring it for maintenance and an oil change. It'd be great if I had an idea what to expect about this pesky 'check tire pressure' light, still.
 

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If you are sure the tire pressure is correct, you can press and hold the reset until it goes out, as stated. I seem to have one tire with a slow leak after a few potholes. When my light comes on, I start the car so the light is on and then top up a tire and check the light. If it goes out, that was the tire. If not, I go to the next until I get no light. If you've done all four and the light is still on, it could be the sensor. I had two get bent up to the point the dealer replaced them, but the light didn't come on. That leads me to believe that a broken sensor might not trigger the light. The other thing that has been mentioned on the forums is the sensors are battery powered. I don't think the battery is replaceable, but the sensor could look good but not respond.
 

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If you have too much air pressure in the tire, the sensor will trigger the light too. I have found the 'pencil type' tire gauges to be widely inaccurate. I picked up a digital pressure gauge and found out that my old pencil gauge was way off the mark. Using the digital gauge I have not had any problems with TPMS lights.

You are going with the tire pressures listed on he drivers door frame right??
 

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If you are sure the tire pressure is correct, you can press and hold the reset until it goes out, as stated. I seem to have one tire with a slow leak after a few potholes. When my light comes on, I start the car so the light is on and then top up a tire and check the light. If it goes out, that was the tire. If not, I go to the next until I get no light. If you've done all four and the light is still on, it could be the sensor. I had two get bent up to the point the dealer replaced them, but the light didn't come on. That leads me to believe that a broken sensor might not trigger the light. The other thing that has been mentioned on the forums is the sensors are battery powered. I don't think the battery is replaceable, but the sensor could look good but not respond.
I'm pretty sure this system is going to notify you with the light on that data is missing from a bad sensor.

Per Rusted Wrench :
"The smart tire pressure sensors transmit 6 data messages every 60 seconds, including absolute pressure, tire pressure, temperature, wheel identifier for position identification and status information containing manufacturer, direction of turning and operating mode. The sensor positions are learned on each drive cycle. The sensor contains a battery whose service life is said to be approximately 10 years.
The sensor only knows the current pressure. It does not know how much is too much or too little. Once the desired tire pressure is set and the system put in learn mode, the system control unit stores the desired pressures and compares them with the currently transmitted pressures from each sensor when they are operating. The control unit makes the decision to illuminate the pressure warning if the current pressures are out of the desired range."

With that much information transmitted by each sensor every sixty seconds, I can't imagine that the receiver wouldn't light the light if it does not receive a packet from one of the sensors in a reasonable time frame.
 

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IYes, the light will come on if there is a sensor bad. I know. (2009 passion coupe). Not sure if they will come on when you have too much, I've filled my tires to 35psi (cold) in hopes of improving gas mileage.

A sensor will cost about $126 to replace at the dealer. I did that once. Then one day I went to put air in one of the front tires while doing a brake job on it, and the stem broke, so I replaced both front tires sensors with regular old rubber tire stems (about a buck each).

I now have only 1 sensor left, and the light is on all the time, but since I carry a tire gauge and check them every couple of fillups, I'm not worried about the tires being low.

I personally will not spend $500 on tire pressure sensors!
 
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