2007 m35 tpms warning failure?

[gene786]

I arose this morning to drive to church, after a block made a left turn and heard and felt a bump. Checked my tire pressure reading, 3 psi in left front tire, about 30 in the other three tires. Road side service guy could not find anything obviously wrong with tire, but he said that he thought I had been driving with low pressure for a while pointing out some pattern on the tire sidewall.

I had not noticed any warnings nor has my wife. A year ago, we did have a low pressure situation with warnings noted.

Most discussions I have found are related to sensor problems. It seems to me that the sensor in all the tires were working since they registered a value. The manual indicated that if there were a problem with the tpms that a warning should come up with on ignition for a minute, did not see that. With spare tire mounted, no warning and no psi reading from the spare.

My plan is to take tire to local shop for repair and/or replacement and then to dealer for evaluation of the tpms. Any comments? Thanks.

[xerexabante]

You have an 07 so you are covered under warranty unless you have over50k miles. Anyway take it to the dealership and make sure you have a little grease to your service rep, this will make your life easier. Good luck and take a look at your Warranty cards for warranty issues. A little reading will not hurt.

[SteveTheTech]

Welcome to NICO!

It is always a smart idea to invest in a manual tire pressure gauge and keep it in the glove box in case something like this happens. If you had the tire gauge you could see what the pressure is currently, so if there is a sensor failure you will still be safe.

The spare tire will not register a reading since it is not programmed to the TPMS unit. It will also most likely set a tire light code for no communication with the sensor at whatever location it is at.

[szh]

It is always a smart idea to invest in a manual tire pressure gauge

Yup!

I strongly prefer to measure regularly with an accurate gauge. I have an Accutire digital model that has 0.1psi resolution (I forget the accuracy specs, but it is better than 0.5psi, as I recall) and really works well!

Z

[gene786]

You have an 07 so you are covered under warranty unless you have over50k miles. Anyway take it to the dealership and make sure you have a little grease to your service rep, this will make your life easier. Good luck and take a look at your Warranty cards for warranty issues. A little reading will not hurt.

Thanks for the reminder. So far tho' I've called the service rep assigned to me for three days and no response. Will make a more sustained effort today.

[gene786]

Welcome to NICO!

It is always a smart idea to invest in a manual tire pressure gauge and keep it in the glove box in case something like this happens. If you had the tire gauge you could see what the pressure is currently, so if there is a sensor failure you will still be safe.

Thanks for the welcome. I do have a manual tire gauge in my trunk. My issue is when I pulled over upon feeling the uneven ride I checked the tire pressure readings on the status menu and it did show 3 pounds psi in the affected tire. So apparently the sensor was working. My complaint is that the alert apparently did not work nor a warning that the alert system was not functional.

It reminds me of the loss of my first and only GM car while driving home in 1966 from Texas upon discharge from the service. The temperature warning light lights up upon ignition, but that only tested the integrity of the bulb. It does not test the integrity of the sensor connection to that bulb. The engine overheated in midsummer in AZ and it was discovered that the sensor connection was hanging free in the breeze.

Certainly, I should check the tires manually, but then why have a warning system?

[SteveTheTech]

A variation of 3 psi after driving is not uncommon and should not have set a light unless it was below 28psi. There a few maybes in this incident in my mind. When hitting a bump it may be possible to compress the sidewall of the tire enough to allow some air to escape. Also the low tire with visable sidewall damage may have been caused by scuffing the wheel against a curb.

I would recommend the dealer for any service with the TPMS system as they have the only tool to service the system.

[gene786]

A variation of 3 psi after driving is not uncommon and should not have set a light unless it was below 28psi. ...I would recommend the dealer for any service with the TPMS system as they have the only tool to service the system.

It was 3 psi, not 3 psi lower than other tires which read 31. Got through to dealer service and I'm on board for 8:15 am. Thanks to all.

[szh]

It was 3 psi, not 3 psi lower than other tires which read 31.

Too low!! I would strongly recommend setting and running at near 36 psi as a reasonable compromise between ride comfort, safety and road harshness.

This also gives you a bit of time to make sure that it does not drop too low.

Keep a pump at home, check bi-weekly and refill to 36 psi (since it is normal for tire pressures to drop 1-2 psi in a couple of weeks - regardless of weather changes).

Z

[SteveTheTech]

Too low!! I would strongly recommend setting and running at near 36 psi as a reasonable compromise between ride comfort, safety and road harshness.

This also gives you a bit of time to make sure that it does not drop too low.

Keep a pump at home, check bi-weekly and refill to 36 psi (since it is normal for tire pressures to drop 1-2 psi in a couple of weeks - regardless of weather changes).

Z

It's a great practice. I would highly suspect that the last time the tires were rotated the sinsors were not reset for their new position. Had it been howing current pressure?

[gene786]

It turns out that I had a puncture in the side wall. The tire was replaced and the pressure system reset. I did not get an answer as to why the low pressure warning did not go on. My fault, I was anxious to leave for another appointment.

Manual tire pumps have been recommended here. Any particular brand comes to mind or is the item generic?

[szh]

Manual tire pumps have been recommended here. Any particular brand comes to mind or is the item generic?

Accutire is the most common brand for digital pressure gauges.

I have this one: http://www.amazon.com/Accutire...r=8-3 (the Accutire MS 5510B Racing Tire Gauge).



It is not perfect ... the mechanism for re-reading is not convenient at all. If you use the side-valve to bleed a little air, it does not re-read, till you take the damn thing off and release pressure and push in again. However, I have gotten used to this little anomaly and love the accuracy of the gauge.

Z

[szh]

Also, these: http://www.ghmeiser.com/dial.htm are good mechanical tire pressure gauges.

Z

[szh]

This one: http://performancetuner.net/DTPG.html is one of the ultimate accuracy ones ... but a bit overkill.

Z

[szh]

A good read: http://www.carbibles.com/tyre_bible_pg2.html. See the section on gauges and tire-pressure systema, etc., about 2/3 of the way down the page.

One funny thing there: "One last note : if you're a motorcyclist, don't carry your pressure gauge in your pocket - if you come off, it will tear great chunks of flesh out of you as you careen down the road...."

Z

[jonlex99]

A good read: http://www.carbibles.com/tyre_bible_pg2.html. See the section on gauges and tire-pressure systema, etc., about 2/3 of the way down the page.

One funny thing there: "One last note : if you're a motorcyclist, don't carry your pressure gauge in your pocket - if you come off, it will tear great chunks of flesh out of you as you careen down the road...."

Z

That last note funny as hell. Who would be stupid enough to ride around with a tire gauge in there pocket.