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yaris2010RS
02-02-2011, 06:52 PM
just a simple question, how does the tire pressure sensor work? i was under the impression that there was a small pressure sensor on the inside of the valve and it was wirelessly transmitted to the computer.

maybe im wrong, now the part that worries me is i recently changed my tires to a seperate set of rims and tires (came off a late 90's civic), should my dash not say i have a tire pressure issue?

billfires
02-02-2011, 07:16 PM
Do you park your car near the original wheels? It took a day or two for my TPMS light to come on initially, as I swapped the snow tires at my father"s garage. I brought the stock wheel/tires home and put them in my truck that is parked next to the Yaris and have only had the light come on once since (65 mile trip). Bill C

CTScott
02-02-2011, 09:59 PM
The sensors are wireless and are part of the stem assembly. The receiver listens for them, but because they can be interfered with, the system is tolerant of no comm conditions. The sensors need to not talk for 20 minutes of the vehicle traveling 5mph+ for the system to decide that the sensor is missing. And, as Billfires mentioned, parking next to the tires that still have the sensors in them will reset the no comm condition.

yaris2010RS
02-03-2011, 12:25 PM
at first i had the tires in the garage next to my car but now they are moved to the basement and i do about 100km a day (and no my basement doesnt follow me around)

yaris2010RS
02-07-2011, 12:40 AM
is there any way to find out if by some odd way there is a sensor inside the tires? do the sensors not need to be linked to the computer?

CTScott
02-07-2011, 07:31 AM
is there any way to find out if by some odd way there is a sensor inside the tires? do the sensors not need to be linked to the computer?

Look at the stems. If they are metal, then they are most likely the TPMS ones. If they are rubber, they are not.

The TPWS ECU needs to have the sensors registered to it, and doing so requires a tool (i.e. the ECU can't auto learn a new set of sensors).

yaris2010RS
02-07-2011, 09:48 AM
thats odd..... so basically my tpms isnt working?

i have a list of stuff to take up with toyota once i get some time and it gets a bit warmer......

CTScott
02-07-2011, 10:16 AM
thats odd..... so basically my tpms isnt working?

i have a list of stuff to take up with toyota once i get some time and it gets a bit warmer......

Does the light come on for a second when you turn the key?

yaris2010RS
02-07-2011, 11:10 AM
no, not that i can recall. i will double check when i finish class

yaris2010RS
02-11-2011, 04:16 PM
sorry for long delay but no the light does not come on for a second when i turn the key. what does this mean? i thought all yaris's came with this and since mine is the RS it definatly should have it right?

CTScott
02-11-2011, 04:45 PM
sorry for long delay but no the light does not come on for a second when i turn the key. what does this mean? i thought all yaris's came with this and since mine is the RS it definatly should have it right?

All USDM ones have had it since 2008 (as it is a US government requirement). Looking at the Toyota.ca site, I actually don't think that yours comes with it.

yaris2010RS
02-11-2011, 04:49 PM
oh......thats odd. but it does clear it up. ill ask at my next oilchange. is the ability there and just needs to be plugged in or is it a completly different system?

CTScott
02-11-2011, 05:13 PM
Pop your passenger glove box and look next to the blower stack for the TPWS ECU. The system is actually fairly simple. It consists of the ECU and the receiver (which is mounted to the rear left C pillar). The indicator LED is driven by the TPWS ECU. The TPWS does not speak to the ECM and actually isn't even a CAN Bus device. The TechStream tool communicates to the TPWS ECU via the older type ISO 9141 spec (AKA OBDII before CAN).

http://i372.photobucket.com/albums/oo163/ctscott329/Misc%20Yaris/TPWSECU.jpg

yaris2010RS
02-11-2011, 05:18 PM
kk, after class i will go out and take a look, thanks.

Bluevitz-rs
02-11-2011, 06:18 PM
Also, your summer tires will simply have rubber valve steams, not the metal ones.

OTA'sTOY
02-11-2011, 06:25 PM
IT IS POSSIBLE IT WAS NEVER INITIATED FROM DEALER DURING PRE DELIVERY INSPECTION

Freedan
02-11-2011, 06:30 PM
Yaris2010RS, count yourself lucky. I wish my car wasn't equip with TPMS/TPWS. Right now I have black electrical tape covering the annoying light because it's quicker than doing the TPMS bypass mods. :laugh:

donchae
02-11-2011, 11:35 PM
All USDM ones have had it since 2008 (as it is a US government requirement). Looking at the Toyota.ca site, I actually don't think that yours comes with it.

just a confirmation, would that mean that my 2007 sedan doesn't have tpms?

CTScott
02-11-2011, 11:58 PM
just a confirmation, would that mean that my 2007 sedan doesn't have tpms?

07's definitely don't have it.

donchae
02-12-2011, 11:19 PM
07's definitely don't have it.

that's good then! i don't have to worry about changing rims all the time.. woop! :w00t: