05 Matrix AWD tire pressure light on - Toyota Nation Forum : Toyota Car and Truck Forums

Robert4524 · 07-08-2009, 03:56 PM

Can anyone tell me how the tire pressure sensor works? I got my wife's 05 Matrix's tires replaced several months ago now and when I got in the car recently I noticed the tire pressure light was on. I checked the tire pressure and a couple needed air. I filled them according to the pressure on the inside of the door and reset the sensor. However, the sensor keeps coming on. Wife says it has been doing it since they replaced the tires, but she neglected to tell me. I am figuring the tire store damaged a sensor. Is there a way to tell this?

Thanks in advance.

Rob

fishexpo101 · 07-08-2009, 05:48 PM

Tire pressure monitor are ABS driven, i.e., if the ABS "sees" that one tire is turning a different speed than the others, it will assume it is low on air.

If the tires are of different sizes or one is grossly worn out - the tire light will come on. Tire pressures should be within 2PSI of each other max - try plumping the tires with more air and see if the tire monitor goes away.

I believe OEM is 30PSI, which is too low IMO, I'd suggest starting at 35PSI and play around with pressures until you find a good comprimise between traction, ride, and fuel economy.

It is possible that one of the speed sensors on the hub got damaged - have to pull the tire off and look at the sending unit (wire) and see if there are obvious signs of damage (cable will run really close to the spring and strut. After this much time has past - be tough to lay blame on anyone - sometimes ABS wheels sensors just go bad/lazy.

mar kolya · 07-09-2009, 10:36 PM

I've had similar problem with my 2005 matrix. And I tried everything including changing tires completely to new ones (I bought a car with three different tire types on it).
But for me the problem was fixed when I reset the sensor differentially.
So, after you checked and fixed tire pressure you should press and hold 'tire sensor reset' button so light turns off. And right after this you need to press and hold it again. After some time the light will blink three times and remain off. I think that this fixes the problem and I saw similar description on some other site. But for sure this can be some kind of mechanical problem and this method won't help.
Good luck.