Jeep Renegade Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter · #1 ·
I had a 2018 Renegade and noticed that the tire pressure display on the dashboard was missing some numbers, like no 34 psi or 37 psi. It would jump right past those numbers. I recently got a 2021 Renegade and it is doing the same thing. Has anyone else noticed this?
 

·
Registered
2015 Trailhawk
Joined
·
724 Posts
Yes, I've noticed this. I assumed it was an analog to digital resolution limitation. It's a tire pressure warning system; not a tire pressure indicating system. I believe it specifically states in the manual not to use it as a substitute for a tire pressure gauge when setting the pressure.
 

·
Registered
2015 Trailhawk
Joined
·
724 Posts
Being a Fiat at heart. I assume the default pressure units are kPa (kilopascals). And I also assume the minimum resolution is 10 kPa which is about 1.5 psi. So if it rounds to the nearest 10 kPa then, after it does the conversion to psi, every few psi change will skip a least significant digit.

For example, 230 kPa = 33.36 psi which rounds to 33 psi. 240 kPa = 34.81 psi which rounds to 35 psi. No 10 kPa increment will round to 34 psi.
250 kPa = 36.26 psi (36 psi), 260 kPa = 37.71 psi (38 psi)

Edit: the default units may also be tenths of a bar which is the same as 10 kPa. Ah, the joy of metric units. If only my life was so simple.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #4 ·
Being a Fiat at heart. I assume the default pressure units are kPa (kilopascals). And I also assume the minimum resolution is 10 kPa which is about 1.5 psi. So if it rounds to the nearest 10 kPa then, after it does the conversion to psi, every few psi change will skip a least significant digit.

For example, 230 kPa = 33.36 psi which rounds to 33 psi. 240 kPa = 34.81 psi which rounds to 35 psi. No 10 kPa increment will round to 34 psi.
250 kPa = 36.26 psi (36 psi), 260 kPa = 37.71 psi (38 psi)

Edit: the default units may also be tenths of a bar which is the same as 10 kPa. Ah, the joy of metric units. If only my life was so simple.
That is so cool! Thanks for the explanation, rsanges!
 

·
Registered
Joined
·
852 Posts
I use the TPMS for informational conditions, not operational conditions; I check with a gauge once a week, no matter what the dash says, and the dash is always off from actual. But if for some reason it says a tire is 30 psi or so, it does warrant a tread check for impaled objects as well as a psi check. That's what I use the TPMS readings for; extremely odd readings.

If anyone is using the dash display for proper tire pressure, it was never designed for that and you are wearing your tires out faster than usual.
 
1 - 5 of 5 Posts
Top