I think I found your problem. I've been doing some more research and although everywhere in the FSM the manual says there are only 4 TPM sensors, the instructions call for "including the spare" when resetting tire pressures. I dug a bit deeper and found that there are actually 5 different DTC codes that can register to the TPMS ECU, meaning that there must be a sensor in the spare. I'm now 99% sure that your problem has to do with your missing spare tire. Hope this helps!

Javier

 

Thank you for your help. Is there anyway someone can take out their spare to see if the light comes on? That way I can figure out for sure what it is before I go to the dealer and spend big bucks on a spare I won't use.

I appreciate all of the imput on this subject and I hope I found the cure to my "check system" light.

 

Like I said before, the spare tire has a sensor but I guess no one believes me....yes the check system light comes on when ur spare tire is not in the trunk..believe me..it happened to me. put the spare tire back in the trunk and re-initialize.

 

I took the spare out. No change. I dropped the pressure in the spare by 50%. No change. I looked at the spare, and it has a rubber valve stem, not a metal one like all the pressure sensor equipped wheels. There is no sensor in the spare.

Javier - there is no data active shown for a 5th sensor. There are only four, and this is consistent across all documentation.

Here's what likely happened - a DTC was set when the other wheels were on the car. The DTC can only be cleared by the "Intelligent Tester." As long as there is a fault, the warning will continue. It's part of the system design to ensure either the system is working and all is well, the system is working and all is not well, or the system is not working and needs maintenance.

As for why don't they use the rotation method, Toyota did on the '05 and '06 Scion tC. It is worthless. By the time you figure out the tire is flat, it is ruined. You can ask my wife all about it. It also does not meet the minimum requirements of the '08 specification. Last but not least, if you replace one tire because it failed, you must replace both tires on the same axle or you will get the trouble code even though everything is actually fine. It's far from foolproof, and it's downright annoying - far more than the TPMS we have.

 

You're right Lance - every single reference I found to the TPMS refers to only 4 sensors. This table, from the 9/15/05 TSB entittled "Tire Pressure Sensing Transmitter Activation Procedure" is what threw me off:



I've seen the spare, and it didn't look like it had a sensor mounted in it. I guess maybe the system is capable of managing five sensors?

Javier

 

So, there isn't any 5 sensors? just 4 for sure? I'm so confused here.

 

Thank you for your help. I will most likely get to the dealer to have them check it out. I will let you know the outcome when I get it back.

Thanks again for your help.

 

I see the TSB, and interestingly enough it is ISx50 specific. However, an Adobe search for C2115 resulted in zero hits, where the same search for C2111, C2112, C2113, and C2114 gave me all the expected results. The key item I check is the data active table. It gives the names of all the data assigned to a subsystem with a short description of what the data describes.

Just to add another reason why I suspect a DTC, check this table from the FSM:

 

was there any resolution to this problem? Im having the same problem but I still have my spare in my car. I just switched back to my TPMS wheels after a 3-4 months of having them off.

 

The LS460 has 5 sensors, but our cars only have 4. In the 460 you see all 5 readings on the display

 

yea our is has only 4 sensors just a dumb question but is the gauge u use accurate? mayb u should try to fill it up a little but more than the reading on the gauge say like 34psi and reset the light again see if that helps

 

make sure its not on the second tire set this will make the light come on when u reinitialize it no matter how many time you do it. Its for like aftermaket wheels. Its for different specs... Hope this helps

 

When your tires are low on air the dash will read "low tire". Check system means there some other problem. I have had the check system come on 2 times in the past few weeks. Each time the dealer told me a sensor was bad. I'm actually about to drop the car off to get sensors replaced.

 

I actually spoke with a rep from service cause I think I am going to have the same problem , had the wheels with the sensors off for about a month now due to one blowing out gonna repalce it soon and then I saw this so I called them up he told me that they might have to reset it at the dealer because they have to use a machine that will initiate the sensors with the vehicle. not sure how valid this is but as soon as I get mine situated if I have the same problem, one thing is for sure I am going to put those sensors in a pipe so I don't have to worry about this when I have another flat or switch out my wheels.

 

There is a different warning when tire pressure is low. I just hope i dont have to go to my dealer because the I dont have one nearby. What does the reinitializing near the steering wheel actually do?