Tire Pressure TPMS accuracy...?

[RubiconRider]

So I lowered the pressure in my tires to 37 PSI today, but my TPMS still reads them at 40 PSI.. Is this normal?

Sponsored

 

[WranglerMan]

It takes alittle bit for the pressure to correct itself

 

[TheLion]

It's pretty close to being accurate based off the arb tire deflator I used. One or the other is accurate, not sure which. However they are only about 1-2 PSI off from each other - not enough for me to care either way

 

[Swanny297]

So I lowered the pressure in my tires to 37 PSI today, but my TPMS still reads them at 40 PSI.. Is this normal?

Takes a bit to level out - TPMS sensors aren’t very accurate most are about +/- 2psi (this is what they were typically spec’d at for ones we used on Colorado/Canyons)

 

[cjaama]

Digging up an older thread here to solicit further opinions.
I just picked up my JLUR Friday. My TPMS is reading 41psi at all four corners. I have a cheap digital gauge that reads 37.5 and two stick-type (looks like a pen) gauges that give different readings, one closer to 40 and one somewhere in between.

Can anyone say how accurate the TPMS is and how they’ve determined its accuracy? I'll probably end up just lowering it a couple to put it somewhere in the middle.

 

[COSJL]

For me it was within 1 psi of the cheap gas station pressure guage. I have already verified this guage to be within 1 psi of my Grand Cherokee tpms readings, so I think they are fairly accurate.

 

[Rhinebeck01]

@COSJL
@cjaama

I would use the TPMS sensor reading on the evic as an approximate.... use to eyeball quickly, to get an idea approx what the psi is.

There is no substitute for checking psi in tires in the early AM, when it is cool out ... before you drive the vehicle.

Do use a known to be accurate gauge.

In regard to your JL's TPMS:

How does the JL/JLU know which tire/rim/wheel is where .....

Well, there are 3 sensors on the chassis that monitor the 4 TPMS Sensors found on the 4 tire (rim) positions.

Info from the 3 chassis sensors is transmitted to the Wireless Control Module. There is no need for a 4th chassis sensor as the computer uses the process of elimination to determine the fourth tire location.

Yes, your JLU/JL knows exactly which rim is where, usually within seconds of a tire rotation for example. Yes, It's all done automatically.

There is a TPMS sensor in the factory mounted spare but it is not read by a chassis sensor/ considered by the computer until it is placed in one of the 4 tire positions.

.

 

[jerseymike]

I always think they are more accurate than the manual guage but not 100% sure

 

[WranglerMan]

My tire gage is digital so it’s more accurate the the EVIC display

 

[RMojitoJL]

my TPMS shows 1-2lbs more than measuring at the valve myself. idc what it shows on screen, as long as i know I'm running what I need to be.

Sponsored