TPMS inaccuracy

[Frenchy]

Sounds like you might have a faulty tire pressure gauge to me. That said a failed TPMS usually throws a code or shows a ridiculous pressure.

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[Rinn69]

Mine is only 1 pound different than my dash gauge. My MPG is within 1 mpg as well after several tanks of gas/adjustment.

@Tim H.
2 questions:
1--Are you running factory size wheels/tires ?
2--What number did you "plug in" to get that close for mpg ?

 

[GTGallop]

Mine is dead nuts on target. Just slow to read and respond.

 

[Cabose-1]

My tpms is pretty accurate. 1 off what any of my guages say. And i have 1 sensor that is always 2psi off. Weird.

 

[airline tech]

If they are off, try resetting the BCM and RTM (Using Forscan and performing a Self-Test - the TPMS sensors transmit to the RTM and the RTM sends the info to the BCM.
This will reset the TPMS system as far as communication goes in transmitting the pressure data.

You can recalibrate them but this requires a high-end scan tool with the TPMS function, I'm not sure if Forscan can do it as I have it on my Autel scanner and honestly have only used it once the whole time i have owned it for the TPMS sensor calibration.
I plan on using it for the Ranger when tire rotation is due (Soon) as the truck won't recognize automatically where the tire is moved (Location). I don't know if tire shops do the relearn.

 

[alcohenusa]

I plan on using it for the Ranger when tire rotation is due (Soon) as the truck won't recognize automatically where the tire is moved (Location). I don't know if tire shops do the relearn.

I can tell you that both of my Fords (2020 Ranger and 2018 Fusion) absolutely learn the location of the TPMS sensors after rotating tires.

 

[Colo_Ranger]

If you live by a Discount Tire, they have a tool that will reset the sensors. I had them set the pressure to 35 psi and then reset the sensors. Now it matches exactly. I know their autoflater is quite accurate on pressure reads. Now my sensors read 35 after being filled. I had one that read 15 psi off before I had DTC recalibrate them.

 

[Discount Tire]

If you live by a Discount Tire, they have a tool that will reset the sensors. I had them set the pressure to 35 psi and then reset the sensors. Now it matches exactly. I know their autoflater is quite accurate on pressure reads. Now my sensors read 35 after being filled. I had one that read 15 psi off before I had DTC recalibrate them.

Thank you for the shout out! I'm happy to hear that your tpms sensors and air pressures are back in line.

 

[reidmefirst]

If you live by a Discount Tire, they have a tool that will reset the sensors. I had them set the pressure to 35 psi and then reset the sensors. Now it matches exactly. I know their autoflater is quite accurate on pressure reads. Now my sensors read 35 after being filled. I had one that read 15 psi off before I had DTC recalibrate them.

We do have one near us, may give it a try. I found some tutorials for recalibrating the TPMS at home too. Instructions seem to vary, but there is one that says to deflate each tire one at a time while waiting for the horn to honk (I guess this tells the system where roughly 0 or some low psi is)? I do have a bunch of jack stands so I could guess I could do this without damaging any of the tires. Will read up on it a bit more before trying, or may just head to the tire shop. Thanks for the tip!

 

[Colo_Ranger]

We do have one near us, may give it a try. I found some tutorials for recalibrating the TPMS at home too. Instructions seem to vary, but there is one that says to deflate each tire one at a time while waiting for the horn to honk (I guess this tells the system where roughly 0 or some low psi is)? I do have a bunch of jack stands so I could guess I could do this without damaging any of the tires. Will read up on it a bit more before trying, or may just head to the tire shop. Thanks for the tip!

You won’t hurt the tires running them to empty with the weight of the truck, just don’t drive on them (duh!) and you’ll be fine. Discount takes about 3 minutes to do, so it’s much less of a hassle, imo.

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