TMPS sensors reading high

[Sandevino]

New 2023 Ram Lone Star 4x4 with factory 18” rims and tires.

Ambient air temp is 80 degrees and all tires are set at 36psi and manually verified. The TMPS sensors all read 37psi and after a few miles the fronts read 38-40psi while the rears read 37psi.

What is the process to reset or retrain the sensors to reflect accurate pressure?

Thanks in advance!

 

[SniperDroid]

Being a difference of 1 psi in your Guage and tpms is quite acceptable as standards go. The increase while driving is normal as the air in the tires warms due to friction between the tire and road , and expands. Thus the reason for setting pressure while tires are cold.

 

[Sandevino]

Being a difference of 1 psi in your Guage and tpms is quite acceptable as standards go. The increase while driving is normal as the air in the tires warms due to friction between the tire and road , and expands. Thus the reason for setting pressure while tires are cold.

Thanks. I get the variance and acceptable range but they do not read accurately when cold.

Every other vehicle I have reads accurately.

 

[SniperDroid]

I have never, in 50 years of driving, been lucky enough to own a Guage that was perfectly accurate. Congratulations!

 

[Sandevino]

I have never, in 50 years of driving, been lucky enough to own a Guage that was perfectly accurate. Congratulations!

Maybe my luck ran out…lol

 

[Dean2]

Being a difference of 1 psi in your Guage and tpms is quite acceptable as standards go. The increase while driving is normal as the air in the tires warms due to friction between the tire and road , and expands. Thus the reason for setting pressure while tires are cold.

Spot on!!!

 

[Jay P]

Elevation also affects the reading. The TPMS sensors read absolute pressure and your tire gauge reads the pressure based on atmospheric pressure and the TPMS is calibrated for sea level. As you go higher in elevation atmospheric pressure drops but the absolute pressure inside the tire is still the same. Some auto manufacturers correct the reading you see via TPMS sensors but most don't so at higher elevations your tire gauge will show a higher pressure than the TPMS shows.

 

[Tulecreeper]

I can spend 20 minutes setting the pressure on all 4 tires until the TPMS reads exactly as the book/sticker says they should when cold, then the next few times I drive the PSI's on all of them are all still acceptable but none of them are the same as any of the other three. They could be anywhere from 2 to 6 PSI higher, but none of them rise at the same rate as any of the others. The TPMS system is not an exact science, it's just a gauge to keep you in the ballpark. When you air up, get them within a couple PSI of where they're supposed to be then forget it.

 

[Sandevino]

Elevation also affects the reading. The TPMS sensors read absolute pressure and your tire gauge reads the pressure based on atmospheric pressure and the TPMS is calibrated for sea level. As you go higher in elevation atmospheric pressure drops but the absolute pressure inside the tire is still the same. Some auto manufacturers correct the reading you see via TPMS sensors but most don't so at higher elevations your tire gauge will show a higher pressure than the TPMS shows.

I’m in Dallas - 700’ above sea level. The TPMS sensors that came with the truck for my trailer tires report the same pressure as the manual gauge.

I think I’ll bring this up with my service advisor when I stop in next week.