A steady TPMS light means at least one tire is 25 percent or more below its recommended pressure. A light that blinks for about a minute and then stays on means the monitoring system itself has a problem, usually a dead or damaged sensor. Check all four tires with a gauge before anything else.
We replace, program and relearn TPMS sensors at our Tyler and Longview shops, and we program the sensors on every wheel and tire package we install.
Why is my TPMS light on?
A steady TPMS light means one or more tires is low. Federal safety standard 138 requires the warning when a tire is 25 percent or more below the vehicle maker's recommended cold pressure. On a tire that should run 35 psi, that's about 26 psi.
That's lower than it sounds. A tire can be well past "a little soft" before the light bothers you, so treat a steady light as real. It isn't the car being dramatic. It's the one dashboard light that's usually right.
| What the light does | What it means | What to do |
|---|---|---|
| Stays on steady | A tire is 25% or more below recommended pressure | Check all four with a gauge, fill to the door sticker |
| Blinks about a minute, then stays on | System fault, often a dead or damaged sensor | Have the sensors scanned |
| Comes on in a cold snap | Air pressure dropped with the temperature | Top up the tires, the light should clear |
| Comes on after new wheels or a rotation | Sensor missing, not programmed or not relearned | Have the sensors programmed and relearned |
TPMS light blinking
A blinking TPMS light means the system can't do its job. The standard requires a malfunction warning that flashes for 60 to 90 seconds when you start the car, then stays lit. The usual causes are a sensor with a dead battery, a sensor damaged during a tire change, or new wheels without sensors.
Continental Tire draws the same line: steady means pressure, flashing means the system. A blinking light won't go away with air. You can fill the tires until they're round as a beach ball and the light will keep winking at you like it's in on a joke.
Tire pressure light on but the tires look fine
Tires can look fine and still be 25 percent low. A radial tire bulges only slightly when it's under-inflated, so your eyes are a terrible gauge. The light on with "fine-looking" tires is usually real low pressure, a cold-weather drop, or a sensor fault.
Cold weather is the classic one in East Texas. Pressure drops about 1 psi for every 10 degree drop in temperature, according to AAA. A 40 degree swing between an October afternoon and the next morning can take 4 psi off every tire.
The tires didn't change overnight. The air just got colder and grumpier, like everybody else at 6 a.m.
Check with a real gauge, cold, before you drive. Fill to the pressure on the driver's door sticker, not the "max" number molded into the tire. If the light clears after a short drive, that was it.
Light still on after you've filled them? We scan the sensors and tell you which one's quit. See TPMS sensor service in Tyler and Longview.
How to reset a TPMS light
Most TPMS lights reset on their own once the tires are filled to the right pressure and you drive for a few minutes. Some vehicles have a reset button or a menu setting, and the exact steps are in your owner's manual. A blinking light won't reset this way, because the problem is a sensor.
- Fill all four tires, plus the spare if your vehicle monitors it, to the door-sticker pressure.
- Drive for 10 to 20 minutes above city speeds so the sensors report in. That's common on many vehicles, but check your manual.
- Use the reset button or menu if your vehicle has one.
- Still on, or blinking? A sensor needs to be scanned, replaced or relearned.
What we find when the light's on
When that light comes on, I'd bet on one of three things: a nail, a cold front, or a sensor that's been running on the same battery since the truck was new.
Candace Sheets came into our Longview shop near closing time with the light on and left this review: "Low pressure light came on. Pulled in close to quitting time unsure if they could even help. They pulled my vehicle in and found a nail in my tire. Plugged it and got me out of there super quick." That's the light doing its job, and us doing ours.
TPMS questions
Is it safe to drive with the TPMS light on?
How long do TPMS sensors last?
Do new wheels need TPMS sensors?
Why does my TPMS light come on when it's cold?
Light on and won't quit? We find the low tire or the bad sensor, then replace, program and relearn it at either shop. See TPMS service in Tyler and Longview, or call Tyler at (903) 500-8557 or Longview at (903) 500-9626.
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