2010 TPMS - Technical Details?

[hefomofi]

I just rotated the tires for the first time on our 2010 Pilot. The TPMS warning came on earlier this week for the first time the temperature dipped below freezing. I aired the tire and the warning went off before I drove off. Amazing stuff.

Is there anyone out there that has additional technical detail on how the TPMS works? I noticed a small sensor with six blue torrents near the front brake. It looked somewhat like a revolver from a toy cap gun.

I am just interested in more detail on how the TPMS works - I'm guessing there is a radio frequency (?) or proximity sensor inside the tire, I've seen the replacement TPMS sensor online for around $38.00 or so. Is the TPMS sensor powered with it's own internally battery?

There has to be some part of this system that senses the position of the TPMS sensor inside the tire, or the TPMS sensor relays a signal to another receiver sensor near the tire itself. Perhaps it is done by angle of the TPMS relative to the frame.

I'm also guessing (not that I'm thinking about it), if a lift kit were put on a Pilot it would potentially put the alignment of the TPMS sensor in the tire to the frame out of alignment.

I'm an engineer by nature so just curious if any other engineers out there have any design/technical details.

[carguy07]

Tire Pressure Monitoring System
An onboard Tire Pressure Monitoring System (TPMS) warns the driver if the air pressure decreases significantly in any tire. The system helps reduce the chance of damaging a tire or losing control of the vehicle due to low air pressure. This is important because a slow leak, such as one that might be caused by a nail or road debris, might not be easily detectable but could cause loss of grip and potentially a blowout.
TPMS uses a sensor mounted on each wheel that continually monitors tire pressure and sends a coded signal to the TPMS electronic control unit (ECU). The process begins with a signal initiator located inboard of each tire on the chassis. The initiator sends a unique signal for each TPMS sensor. Then the TPMS sensor sends tire pressure data to the TPMS ECU, which compares the values for each tire's pressure against an acceptable range of pressures. When a tire's pressure drops significantly below the proper level, an alert will appear on the information display screen.
On the Pilot Touring model, the system can display the air pressure in all four tires simultaneously via the Multi-Information Display (MID). At the driver's preference, the MID can continually show the air pressure in all four tires. Regardless of whether the driver chooses to monitor the pressures, a warning will still occur if a tire drops significantly below specification.


tpms - How it works - service manual scans - Acura MDX Forum : Acura MDX SUV Forums

[rocky]

sweet thanks

[hefomofi]

Thank You for the info...

There has be some type of battery in the sensor in the tire; I find that interesting...if there is a "watch-like" battery in the sensor in the tire; in that a watch-sized battery is now designed to last outside in sub-zero temperatures and with all the road bumps/vibration.

I've seen similar backup/CPU control system "reboot" batteries lasting over twelve years now in computer security sensor system; but these batteries are all in climate controlled centers.

Found this as a side note, while not a pilot, shows where the Honda sensor is mounted in proximity to the rim; and how the sensor would have to be replaced if the tire is dismounted incorrectly as happens in the video.

YouTube - Episode #85 - Honda Fit TPMS Sensors in Older Wheels

YouTube - Episode #85 - Honda Fit TPMS Sensors in Older Wheels

[hefomofi]

....looks like there already was an earlier thread on the battery details...

TPMS : batteries?