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I picked up my XC90 this July, have never checked (nor inflated the tire pressure) the usual way with my digital pressure gauge, until today.

I have never suspected the accuracy of TPMS, until I noticed a gradual drop in MPG over the past month, especially after I have completed a trip with over 80% on highway and under Ecco mode, the MPG at gas pump was 18.3. Initially, I thought the drop in MPG was completely due to the weather (while in fact, it's pretty warm up here in NYC). Still, I had to move my lazy ass to get the digital gauge out, and OMG, my all four tire pressures were under 33, the label shows it needs to be 38, while TPMS showed 39. I took my car to a gas station immediately which is like half mile away, and inflated all four to 41, (the gauge there also showed a low 30ish). After reboot, guess what, TPMS also showed 41!!!

That means I have driven an under inflated XC90 for an unknown amount of time. Looks like, I can't count too much on TPMS, still have to check tire pressure the same old way.
 

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I picked up my XC90 this July, have never checked (nor inflated the tire pressure) the usual way with my digital pressure gauge, until today.

I have never suspected the accuracy of TPMS, until I noticed a gradual drop in MPG over the past month, especially after I have completed a trip with over 80% on highway and under Ecco mode, the MPG at gas pump was 18.3. Initially, I thought the drop in MPG was completely due to the weather (while in fact, it's pretty warm up here in NYC). Still, I had to move my lazy ass to get the digital gauge out, and OMG, my all four tire pressures were under 33, the label shows it needs to be 38, while TPMS showed 39. I took my car to a gas station immediately which is like half mile away, and inflated all four to 41, (the gauge there also showed a low 30ish). After reboot, guess what, TPMS also showed 41!!!

That means I have driven an under inflated XC90 for an unknown amount of time. Looks like, I can't count too much on TPMS, still have to check tire pressure the same old way.
You inflated a cold tire to 41 or a hot tire to 41?
Also when you checked and they were 33, was that hot or cold?

Makes a mountain of a difference.
 

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I picked up my XC90 this July, have never checked (nor inflated the tire pressure) the usual way with my digital pressure gauge, until today.

I have never suspected the accuracy of TPMS, until I noticed a gradual drop in MPG over the past month, especially after I have completed a trip with over 80% on highway and under Ecco mode, the MPG at gas pump was 18.3. Initially, I thought the drop in MPG was completely due to the weather (while in fact, it's pretty warm up here in NYC). Still, I had to move my lazy ass to get the digital gauge out, and OMG, my all four tire pressures were under 33, the label shows it needs to be 38, while TPMS showed 39. I took my car to a gas station immediately which is like half mile away, and inflated all four to 41, (the gauge there also showed a low 30ish). After reboot, guess what, TPMS also showed 41!!!

That means I have driven an under inflated XC90 for an unknown amount of time. Looks like, I can't count too much on TPMS, still have to check tire pressure the same old way.
I spoke to a Volvo dealer last night about winter tire packages and asked him about tpms. He told me that there Volvo oem winter packages don't include tpms sensors. He said it's because the tpms are particularly inaccurate under rapidly changing winter temperatures. So when they install these winter packages, they disable the tpms readings in Sensus. Then enable them again in the spring when the original tires go back on.

Not sure if this is true or just him trying to justify why these winter packages don't include tpms sensors, but that's what he told me...

Sent from my SM-G920W8 using Tapatalk
 

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I picked up my XC90 this July, have never checked (nor inflated the tire pressure) the usual way with my digital pressure gauge, until today.

I have never suspected the accuracy of TPMS, until I noticed a gradual drop in MPG over the past month, especially after I have completed a trip with over 80% on highway and under Ecco mode, the MPG at gas pump was 18.3. Initially, I thought the drop in MPG was completely due to the weather (while in fact, it's pretty warm up here in NYC). Still, I had to move my lazy ass to get the digital gauge out, and OMG, my all four tire pressures were under 33, the label shows it needs to be 38, while TPMS showed 39. I took my car to a gas station immediately which is like half mile away, and inflated all four to 41, (the gauge there also showed a low 30ish). After reboot, guess what, TPMS also showed 41!!!

That means I have driven an under inflated XC90 for an unknown amount of time. Looks like, I can't count too much on TPMS, still have to check tire pressure the same old way.

Sorry, I'm still new...where in the Sensus does it show TPMS info? I know the alert/signal can come on...but didn't know it will show the exact pressure.

Thanks,
 

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Just passed 350 miles on our new XC90 and got a message on the screen noting that TPMS Service is required. I checked all of the tires and it they were all properly inflated. The tire pressures are also properly displayed on the Sensus display, so I'm not sure what the fault is. I guess this will be our first visit to the service department.
 

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I spoke to a Volvo dealer last night about winter tire packages and asked him about tpms. He told me that there Volvo oem winter packages don't include tpms sensors. He said it's because the tpms are particularly inaccurate under rapidly changing winter temperatures. So when they install these winter packages, they disable the tpms readings in Sensus. Then enable them again in the spring when the original tires go back on.

Not sure if this is true or just him trying to justify why these winter packages don't include tpms sensors, but that's what he told me...

Sent from my SM-G920W8 using Tapatalk
That is interesting my dealer said that they were built in, he definitely did not say they were not needed with the winter tire pacakage

I wanted to ask this question too because I use a pretty good tire gauge and I always check my tires cold. I noticed that the tpms is about 1.5 more than the gauge every time so I am not sure what to trust but my gauge never let me down.
 

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I have the winter tire package and the TPMS works just fine. Granted I bought the package from my dealer but installed the wheels myself.
 

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Just passed 350 miles on our new XC90 and got a message on the screen noting that TPMS Service is required. I checked all of the tires and it they were all properly inflated. The tire pressures are also properly displayed on the Sensus display, so I'm not sure what the fault is. I guess this will be our first visit to the service department.
Quick update, after visiting our local dealer, they were not able to find anything other than a "software problem." All the tires were properly inflated and all the TPMS sensors in the tires were functioning properly. They just reset the warning message and told me to drive it around and see if it came back on.

Well, after 5 days of driving, the message came back on again. Still looks like tire pressure is being properly reported by the system, so I'm not sure what the fault is about. Just dropped off our XC90 for its second visit to the service department in less than 2 weeks of ownership. Hope this isn't a bad omen, but we've never had these kinds of issues with our past vehicles, 3 of which were also brand-new or newly re-designed models. Hope they can fix it before we leave on Friday for a Presidents' weekend Tahoe ski trip (one of the main reasons we bought the vehicle).
 

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I will manually check my tire pressure today (cold, ~39°) and report the findings. The TPMS has been consistently reporting:

FL FR
44 44

RL RR
43 43

psi

Strange as it hasn't changed the last few times I've checked it. And IIRC it was showing "Updating..." for quite some time.

Standby...
 
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