GEN 2 Tyre rotation and TPMS sensor

[wheelman55]

Now would this get rid of the idiot tire indicator on the dash. I have the rear passenger showing trouble etc and the tires fine.

I get the idiot light tire icon when pressure is below 30 psi. Maybe that’s what is causing your light to be on??

 

[OriginalToken]

Now would this get rid of the idiot tire indicator on the dash. I have the rear passenger showing trouble etc and the tires fine.

What pressure is it showing?

If it is below a certain point (I think 31 PSI?) it will show as bad, even though you know it is good. With Fordscan you can go in and rest this trouble point to a lower level. I know when I air down for sand the trouble indicator is on the entire time.

T!

 

[goblues38]

The system DOES NOT automatically know the position of each wheel/tire assembly when they are moved to a different position on the vehicle.

The system only knows the sensor ID and the position that said sensor ID has been trained to. When you rotate the tires you need to perform the TPMS reset outlined in the Owner’s Manual:


Performing the System Reset Procedure
Read the entire procedure before attempting.
1. Drive the vehicle above 20 mph
(32 km/h) for at least two minutes, then park in a safe location where you can easily get to all four tires and have access to an air pump.
2. Place the ignition in the off position and keep the key in the ignition.
3. Cycle the ignition to the on position with the engine off.
4. Switch the hazard flashers on then off three times. You must accomplish this within 10 seconds. If you successfully enter the reset mode, the horn sounds once, the system indicator flashes and a message shows in the information display. If this does not occur, please try again starting at Step 2. If after repeated attempts to enter the reset mode, the horn does not sound, the system indicator does not flash and no message shows in the information display, seek service from your authorized dealer.
5. Train the tire pressure monitoring system sensors in the tires using the following system reset sequence starting with the left front tire in the following clockwise order: Left front - driver side front tire, Right front - passenger side front tire, Right rear - passenger side rear tire - Left rear, driver side rear tire.
6. Remove the valve cap from the valve stem on the left front tire. Decrease the air pressure until the horn sounds.
Note: The single horn tone confirms that the sensor identification code has been learned by the module for this position. If a double horn is heard, the reset procedure was unsuccessful, and you must repeat it.
7. Remove the valve cap from the valve stem on the right front tire. Decrease the air pressure until the horn sounds.
8. Remove the valve cap from the valve stem on the right rear tire. Decrease the air pressure until the horn sounds.
9. Remove the valve cap from the valve stem on the left rear tire. Decrease the air pressure until the horn sounds. Training is complete after the horn sounds for the last tire trained, driver side rear tire, the system indicator stops flashing, and a message shows in the information display.
10. Turn the ignition off. If two short horn beeps are heard, the reset procedure was unsuccessful and you must repeat it. If after repeating the procedure and two short beeps are heard when the ignition is turned to off, seek assistance from your authorized dealer

Sorry...but this is wrong and not needed.

Drive the car 10 miles...and you are done....here is how it works on a very high level.

There are parts (sorry not an engineer) in the TPMS inside the wheel that create an electrical current due to the centrifical forces of a rotating wheel. It can take 5-10 miles for this to build up enough charge. Thats why a spare with a TPMS does not show up right away.

Pretty soon, all the 4 active wheels have enough charge if you will and they create field....the trucks sensors read the time it takes to read each wheel and thats how they know which corner is being reported.

I bought a TPMS learn tool when i got my TPMS installed in my spare....have never had to use it.

 

[engine45]

Thank you fellas. That could be it. I keep the rears 29-30 psi. I’ll put a few pounds in and see what’s up then.

 

[OriginalToken]

Sorry...but this is wrong and not needed.

Drive the car 10 miles...and you are done....here is how it works on a very high level.

@FordTechOne has already acknowledged that this technique may not be needed today. It appears the manual may be referencing older vehicles, and has not been brought up to date. For sure, you CAN do the technique listed on todays trucks (I did it this past week on a couple of my 2020 company trucks, just to see if it worked), the system will correctly identify the location of each wheel using this technique, but you do not appear to have to do this unless you want to.

There are parts (sorry not an engineer) in the TPMS inside the wheel that create an electrical current due to the centrifical forces of a rotating wheel. It can take 5-10 miles for this to build up enough charge. Thats why a spare with a TPMS does not show up right away.

Pretty soon, all the 4 active wheels have enough charge if you will and they create field....the trucks sensors read the time it takes to read each wheel and thats how they know which corner is being reported.

I bought a TPMS learn tool when i got my TPMS installed in my spare....have never had to use it.

Your above does not explain why I can change the pressure (when not changing tire locations) in my tires and have correct dashboard indications before leaving the driveway. It also would not allow you to use the TPMS learning tool while the truck was not in motion.

Your description above is not how the TPMS works. The TPMS sensors in each wheel have a battery, there is no "charge" to build up. Battery less TPMS have been in development for a while, but pretty much all of the fielded systems today use a battery.

Some sensors do use centrifugal forces to tell when a tire is rolling and possibly how fast it is rolling. This allows the TPMS to change modes. It can be in a power saving mode while stationary, and update more often while rolling.

In the case of the Ford system it transmits the pressure readings every 6 hours if it is not rolling, and every 15 to 60 seconds while rolling.

" the trucks sensors read the time it takes to read each wheel and thats how they know which corner is being reported." How do they read time? What time are they reading? What truck sensors?

T!