TPMS not that accurate?
10-08-2017, 02:38 PM
#1
TPMS not that accurate?
hi everyone i went to put air in my tires today at the gas station using my psi checker thing which i have. the back tires match the tpms in the car and with my personal one, but the front tire right side in the car shows 31 while i got 35, also the left front tire in the car tpms shows 35 while mine showed 31. its as if the system mixed up the left and right front tires. I never got a service tpsm message so i assume everything is fine but its weird. right now back tires show 33 psi, front left shows 35 and front right shows 31 all with the tpsm in the car
10-08-2017, 02:51 PM
#3
Burning Brakes
I do believe they have an inertial switch in them and they need to be driven to activate. When they are dormant they only send out a signal infrequently. As far as accuracy goes one of mine is out by nearly 5 PSI high and on a hot summer day freeway drive will trigger a TPMS high pressure warning even though the cold inflation was 35 PSI with an analog gauge.
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mangahas (10-08-2017)
10-08-2017, 02:54 PM
#4
I do believe they have an inertial switch in them and they need to be driven to activate. When they are dormant they only send out a signal infrequently. As far as accuracy goes one of mine is out by nearly 5 PSI high and on a hot summer day freeway drive will trigger a TPMS high pressure warning even though the cold inflation was 35 PSI with an analog gauge.
oh ok fair enough so i guess its not that big of a deal, and il give it a good drive to see what happens, all i pretty much did after was take 2 mins drive home pretty slow and parked so i guess the tires didn't get a chance to fully update properly.
Last edited by mangahas; 10-08-2017 at 03:00 PM.
10-08-2017, 03:40 PM
#5
Team Owner
Sounds like what I'm seeing from OnStar when my Equinox hasn't been driven in a couple of days and they send me a notice about my car's tire pressures. One tire only had 31 lbs instead of the usual 35, according to them. But after I got in the car the next day and drove it to town, all 4 tires had 35 lbs.
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mangahas (10-08-2017)
10-08-2017, 04:49 PM
#6
Sounds like what I'm seeing from OnStar when my Equinox hasn't been driven in a couple of days and they send me a notice about my car's tire pressures. One tire only had 31 lbs instead of the usual 35, according to them. But after I got in the car the next day and drove it to town, all 4 tires had 35 lbs.
10-08-2017, 04:54 PM
#7
Team Owner
10-08-2017, 04:57 PM
#8
Le Mans Master
hi everyone i went to put air in my tires today at the gas station using my psi checker thing which i have. the back tires match the tpms in the car and with my personal one, but the front tire right side in the car shows 31 while i got 35, also the left front tire in the car tpms shows 35 while mine showed 31. its as if the system mixed up the left and right front tires. I never got a service tpsm message so i assume everything is fine but its weird. right now back tires show 33 psi, front left shows 35 and front right shows 31 all with the tpsm in the car
Unlike some newer cars, the C6 does not automatically detect which signal belongs to which tire. The association is established during the TPMS re-learn process. You can set it up to display the right rear as the left front if you want.
10-08-2017, 05:32 PM
#9
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hi everyone i went to put air in my tires today at the gas station using my psi checker thing which i have. the back tires match the tpms in the car and with my personal one, but the front tire right side in the car shows 31 while i got 35, also the left front tire in the car tpms shows 35 while mine showed 31. its as if the system mixed up the left and right front tires. I never got a service tpsm message so i assume everything is fine but its weird. right now back tires show 33 psi, front left shows 35 and front right shows 31 all with the tpsm in the car
10-08-2017, 06:04 PM
#10
Safety Car
The most likely explanation is that the readings for the front tires are swapped. This is easy to do if the TPMS re-learn was performed in the wrong order or if the wheels were rotated.
Unlike some newer cars, the C6 does not automatically detect which signal belongs to which tire. The association is established during the TPMS re-learn process. You can set it up to display the right rear as the left front if you want.
Unlike some newer cars, the C6 does not automatically detect which signal belongs to which tire. The association is established during the TPMS re-learn process. You can set it up to display the right rear as the left front if you want.
the fronts are reading opposite of their actual locations.
10-08-2017, 06:19 PM
#11
The most likely explanation is that the readings for the front tires are swapped. This is easy to do if the TPMS re-learn was performed in the wrong order or if the wheels were rotated.
Unlike some newer cars, the C6 does not automatically detect which signal belongs to which tire. The association is established during the TPMS re-learn process. You can set it up to display the right rear as the left front if you want.
Unlike some newer cars, the C6 does not automatically detect which signal belongs to which tire. The association is established during the TPMS re-learn process. You can set it up to display the right rear as the left front if you want.
thats probably the reason, but can i ignore it or should i tell the dealer
10-08-2017, 06:27 PM
#12
Le Mans Master
If you don't mind you can ignore it forever. Or you can have the wheel shop correct it the next time you buy tires. Or you can correct it yourself with a relatively cheap TPMS tool. You can probably get somebody to lend you one for free.
10-08-2017, 06:46 PM
#13
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10-08-2017, 06:55 PM
#14
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Sounds like a bad TPMS sensor.
In have a 2011 GS and all the tires are inflated to exactly 31 PSI (cold) and checked with a very accurate tire guage. The DIC also indicates 31 PSI on 3 of the tires (shows that the sensors are really very accurate) ... but the left rear only shows 28 PSI on the DIC.
At times, that left rear will just show XX on the DIC, and other times it shows 28 PSI.
Obviously a bad TPMS sensor that needs to be replaced.
My guess is that the OP has a bad TPMS sensor.
.
In have a 2011 GS and all the tires are inflated to exactly 31 PSI (cold) and checked with a very accurate tire guage. The DIC also indicates 31 PSI on 3 of the tires (shows that the sensors are really very accurate) ... but the left rear only shows 28 PSI on the DIC.
At times, that left rear will just show XX on the DIC, and other times it shows 28 PSI.
Obviously a bad TPMS sensor that needs to be replaced.
My guess is that the OP has a bad TPMS sensor.
.
Last edited by Turbo6TA; 10-08-2017 at 06:56 PM.
10-08-2017, 06:59 PM
#16
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10-08-2017, 08:14 PM
#17
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Go to Discount Tire and ask them to reset the sensors. You'll then have the DIC reporting the correct locations. Then bleed 4 psi from the right front. Done deal.
10-09-2017, 02:36 PM
#19
Pro
I use a very accurate gauge and get 31 PSI cold yet the TPSM always shows 29 psi cold. I've come to believe that the tire pressure monitoring system is to alert you of any sudden variations rather than tell you exactly want your tire pressure is in each tire
10-09-2017, 04:42 PM
#20
Team Owner
And mine take 20 miles to update the first time after leaving the garage...2 minutes is not enough.
Last edited by cclive; 10-09-2017 at 04:45 PM.
