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My tyre pressure monitor light came on this morning, telling me to reset pressures and showing all 4 tyres red. I'll check pressures tomorrow, but any idea why all 4 would show up at once?
500 Tyre pressure monitor question
- Thread starter Fiat500newbiekitty
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500 Tyre pressure monitor question
Well it could just be that all four tyres are under pressure, in which case they will show up if your display does indeed show all four individual tyres. On our Hyundai i10, the TPMS light comes on if it detects low pressure but doesn't tell you which tyre so it forces you to check all four tyres until you find the one that is low on pressure.
As a note, 3 years or so ago, I bought a brand new pre-reg 500 from a Fiat dealership and I had to inflate all four tyres myself on their forecourt because they couldn't be arsed to do some simple basic checks before I started my journey back up North. That particular 500 TA wasn't fitted with TPMS, I only noticed because both front tyres looked well under pressure before I even got into the car. When I put the pressure monitor on, both front tyres were down to 10 psi.....:bang: A pretty crap state of affairs when you've just parted with hard earned cash and the dealership clearly didn't even bother to PDI the car properly.
As a note, 3 years or so ago, I bought a brand new pre-reg 500 from a Fiat dealership and I had to inflate all four tyres myself on their forecourt because they couldn't be arsed to do some simple basic checks before I started my journey back up North. That particular 500 TA wasn't fitted with TPMS, I only noticed because both front tyres looked well under pressure before I even got into the car. When I put the pressure monitor on, both front tyres were down to 10 psi.....:bang: A pretty crap state of affairs when you've just parted with hard earned cash and the dealership clearly didn't even bother to PDI the car properly.
OP
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Thank you I'll check each tyre pressure tomorrow. Just getting used to have this feature and didn't realise it highlights all 4 even if one is off.
Your 500 dealer sounded very lazy!
Funky Spike
Member
The TPMS goes off on my car when I swap between winter and summer wheels, not straightaway but usually a day or two after. I always check the pressure again, even though I checked them when I put them on and once I reset the TPMS it's fine.
I see you've just got the car, has it had any new tyres?
Spike
I see you've just got the car, has it had any new tyres?
Spike
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From my experience with pressure, it doesn't take much of a drop to trigger the message. Adding extra air painless. Discovered that couldn't reset the sensors until following morning when tyres completely cold. Nothing in handbook or online told me this. Hope this helps.
TrevC
Established member
My 500 didn't have a TPMS, but the 500X I have now does. The system is called iTPMS, the "i" standing for indirect. It derives changes in pressure by measuring differences in the rotational speeds of the wheels.
Last week I swapped the tyres front to rear, and a couple of days later the TPMS warning came on. Pressures checked out ok so I reset the system and it hasn't recurred. Amazingly the handbook explains that this may happen! Makes sense really as I changed the relative diameters of the wheels so the system has to be re-calibrated.
Direct TPMS, as fitted to our Suzuki, can be identified by metal valve stems, secured to the rim by a nut. These will generally give an actual pressure reading for each wheel.
Last week I swapped the tyres front to rear, and a couple of days later the TPMS warning came on. Pressures checked out ok so I reset the system and it hasn't recurred. Amazingly the handbook explains that this may happen! Makes sense really as I changed the relative diameters of the wheels so the system has to be re-calibrated.
Direct TPMS, as fitted to our Suzuki, can be identified by metal valve stems, secured to the rim by a nut. These will generally give an actual pressure reading for each wheel.
ahmett
Prominent member
When i got my car the pressures were 45 psi! = )))
First generation TPMS had sensors in each wheel with a battery in each, this system gave excellent monitoring but suffered from valve stem sealing issues, it was also more expensive to fit and maintain(often the sensor had a non replaceable battery, pretty stupid)
So makers went "indirect" and use the ABS sensors to detect differences in speed the theory being a low pressure wheel has a different radius so trips the system.
Personally I think the above is a crap system, fitted because all new cars must have it so its the cheapest option, problem is its way less accurate rather than 3Lb down its more like 10 until it trips, just think what a 100 miles at 70 would do if your tyre was down nearly a third?
So makers went "indirect" and use the ABS sensors to detect differences in speed the theory being a low pressure wheel has a different radius so trips the system.
Personally I think the above is a crap system, fitted because all new cars must have it so its the cheapest option, problem is its way less accurate rather than 3Lb down its more like 10 until it trips, just think what a 100 miles at 70 would do if your tyre was down nearly a third?
TrevC
Established member
No idea if the batteries in the Suzuki sensors are replaceable. To view the tyre pressures you have to drive the car first, then stop and go to the TPMS in the menu on the screen. This is because they are powered via a centrifugal switch so the battery only gets drained when the car is moving.
Not true at all these systems are very quick to note a drop in tyre pressure, they can't give an accurate pressure because they are not directly addressing the pressure in the tyre, but they can very quickly tell when the pressure changes.
