Help with warning light! ( ! )

Tire pressures are posted on the driver's side door jam by Toyota as 35 psi front / 33 psi rear. Many Prius owners run at 42 front and 40 rear. Get yourself a pressure gauge and check your tire pressure at least every couple of weeks. Don't drop below the 35/33 pressures.

 

Don't forget to "recalibrate" the pressure sensors after you inflate your tires.

 

My light came on 1 mile from home tonight--a 56 min. ride home in horrid snow conditions,--usu. it is a 25 min. ride. I have never had this light come on before--I have 4 snows on--no sensors. It was first blinking, and then stayed on steady. It's a 2007--2nd year with snow tires on. Should I be worried?

 

There is a button to lower left of the steering wheel. I do not remember if there is any special car configuration that needs to be in place before you push the button. Check your manual...

 

Oops....

 

Press and hold the little black button until the light starts blinking, its next to the key button under the steering wheel, near where your knee is.

tjoe78, depends on if your tire shop moved the sensors to your snow tires.
Check your tire pressure, you may have hit a nail.

 

The car asks the tire sensors for pressure readings every now and then. Sometimes there will be a glitch and the tire pressure all around is fine, but the light still comes on. It never hurts to make sure your tires are properly inflated.

If the sensors don't respond after a while, the car thinks all tires are flat, so the light comes on. If you store your summer tires, inflated, in your garage, the car may ask the summer tires sitting next to the car if the pressure is good and the tires respond yes. Then you drive away on your snows and the car gets out of range of the sensors in the summer tires. The next time the car asks, and gets no response, the light comes on.

Poor confused car, poor confused driver...:violin:

 

I am curious.... You have two sets of tires and wheels, but only one set has sensors? I know the Land Cruisers have the capability on having two sets of programmed sensors and can be switched between the two by way of a button in the glove box...
But, sofar as I know.... Prius can only "see" one set at a time without reprogramming each time you change the sensors....
If you have a TPWS (Tire Pressure Warning Sensor) light blinking for 10-20 seconds then going solid, you most likely have some sort of malfunction in the system. I would recommend having your local dealership check for codes.

 

Bill,
I had no problems until I brought our 2008 Prius in for the 5000mi. service. One week later the TP warning light came on. Took it in and they said the pressure was off and re-inflated. Two weeks later (today) warning comes on again. No problems before the 5000, problems after. Any chance the service guys messed things up?

 

There's always a chance the service guys messed things up. Humans have a great capacity to do that, present company included. But I suspect one or more tires was low, just as they said. Now the issue is finding out why the tire(s) lost air. The seal between the tire and the rim is a possibility, but unlikely; occasionally a rim weight will loosen the bead. A more likely scenario is either something going through the wall or tread of the tire, or a leaky valve core. Since your car is new, lion46, ANY problem is covered by the bumper-to-bumper warranty. Ask the dealer to make your tires stop leaking.