Low Pressure Indicator Light Threshold Pressure

[DesertRatR]

I have a 2010 Yaris Hatchback. Sticker on door frame indicates preferred pressure is 32 psia. What is the set point threshold at which the low pressure indicator illuminates? I called the dealer and the service writer I spoke to wasn't real knowledgeable.

[CTScott]

The service manual only states that a loss of more than 5.8 psi in 30 seconds will trigger the indicator or the pressure dropping below an unspecified threshold. Looking at the TechStream data for the TPMS ECU that I have on my test bench, then "IDn Initial Threshold of Low Pressure" is set to 24psi, which would be a 25% drop in pressure from the OEM recommended 32 psi.

[DesertRatR]

Thank you for the reply. I checked the tires after the light stayed illuminated upon cold start this morning, at an ambient temperature of about 72F. Three tires were above 30 psi by varying amounts. One was at 28 psi. I inflated it to 33 psi and made sure the other three were reading 33 psi. The light did not illuminate. I wonder why Toyota won't share the threshold with even dealers?

[Astroman]

Damn if Scott got a nickel for every helpful post he'd have a crapload of nickels. :thumbsup:

[BIGTAZ351]

Astroman,
He'd have at least enough to make "Crashy" a "no cost" project...and probably put gas in it too.

I see Scott added another Yaris to his garage. They'r like potato chips you cant have just one...I'm thinking when my 2010 is paid off I'll get another one....

[yarisugi]

Forget Siri. WE NEED A CTScott APP.