air pressure sensor problem

[johnm]

Lately the dic displays a high tire pressure warning shortly after starting the car. As I drive the car the dic indicates a high pressure warning in one tire then a few seconds later in another tire then another over and over. The computer says the pressures are in the
42 to 44 psi, the actual hot tire pressures are always 34 to 35psi. Is it possible all the sensors are bad? Or is this a computer probleqm. Anyone had any similar experience. Thanks

 

[c4c5specialist]

HI there

Disconnect your negative battery cable for about 4 mins and then reconnect and take for a test drive.

Let us know how you made out.

Allthebest, c4c5

 

[johnm]

Disconnected the negative pole on battery. The dic read zero air pressure for the first 10 miles, then read 20psi for the rest of the trip
The second time I drove the car, the pressures read 42-46 and the high
pressure warnings returned on all wheels. My warranty expires in 5 days so I think I will run it into the dealership. Thanks for all your help.johnm

 

[johnm]

Took my car in yesterday for the tire pressure sensor problem. A little embarrassing as it turns out the sensors were working properly, I had to much air in the tires. Apparently my tire gauge that I have used forever on all my other vehicles (that don't have sensors) is not accurate. They reset the pressures and no more warnings. Wasn't a total wasted trip they did fix the transmission leak I found the week before. Thanks again for the help

 

[Mac]

Interesting to learn the pressure sensors are so accurate... and nice to get the tranny leak fixed too!

-Mac

 

[Red Vette]

Took my car in yesterday for the tire pressure sensor problem. A little embarrassing as it turns out the sensors were working properly, I had to much air in the tires. Apparently my tire gauge that I have used forever on all my other vehicles (that don't have sensors) is not accurate. They reset the pressures and no more warnings. Wasn't a total wasted trip they did fix the transmission leak I found the week before. Thanks again for the help

I use a digital tire pressure gage on my 02 coupe and 08 convertible and if there is any discrepancy between the pressure reading on the gage and the DIC, I recheck with another digital gage. I find the digital gages to be very accurate, provided the batteries are okay. Also have found that the tire pressure readings on the DIC are accurate for both the C5s and C6s, and for that matter, on my 1994 C4 when I still owned it.
Barrett
Barrett

 

[Pourboire]

Tire Pressure Monitor system not reporting low tire pressure

Purchased 2011 Grand Sport corvette which now has 1000 miles. I was surprised to get a warning from On-Star that one of my tires was under inflated by 9 psi (should be 30 and measured 21psi). If the system is reporting this via on star how come it did not give me a warning on the dash. When I received the e-mail, sure enough the pressure was down by 9 psi and still no indication of a problem on the TPMS light. Does anyone know waht the threshold level is before it reports a problem in real time to the driver. Could this also be an indication that there is something wrong with the internals since I have had 4 check engine light warnings (PO442 code which is emissions) in which dealership can not locate the problem.

Checked with a local reputable Chevrolet dealership in Phoenix instead of the inept one in Scottsdale. They took the time to inform me that the C6 corvette with the run flat tires will not activate the Tire Pressure Monitor System dash board light until the pressure drops tp 6 psi from the recommended 30 PSI. In light of the aforementioned, it would be wise to check tire pressure readings with the on-board system which is extremely accurate. Not sure why they set the threshold so low. Want to thank Dad for is inputs regarding Check Engine Light. Chevrolet refuses to take it to a higher level to resolve problem so I will try a different dealership which has trained Corvette mechanics on staff. As a backup, I purchased a On Board Diagnostic Sytem to monitor this problem if they can't resolve this issue. I figure the item failing will eventually permanently fail and allow any dealership to resolve problem. The lesson I learned from these incidents is that the Chevrolet technical support is worthless. I think my dog knows more about cars than these service technicians who's only concern in the morning is what tie to ware.

 

[Dad]

Could very well be the gas cap seal is dirty or it was not tightened correctly.

My grandson drives his '08 Impala on a dirt road and we have to clean the seal and knock out code P0440 Evaporative Emission (EVAP) System every few months.

Sorry, now back to the TPMS problem..............

 

[johnm]

tire pressure monitor

I think it is a little disturbing that government motors knows what my air pressure is in my tires. My new yukon with onstar tells me when to change the oil and when there is service required. I was speaking to the on star "Lady" the other day and she new where I was and when I shut the car off. She also told me all engine codes that may appear will automatically be sent to my dealership. I don't know about the rest of you but that is a little more than I am comfortable with. se

Purchased 2011 Grand Sport corvette which now has 1000 miles. I was surprised to get a warning from On-Star that one of my tires was under inflated by 9 psi (should be 30 and measured 21psi). If the system is reporting this via on star how come it did not give me a warning on the dash. When I received the e-mail, sure enough the pressure was down by 9 psi and still no indication of a problem on the TPMS light. Does anyone know waht the threshold level is before it reports a problem in real time to the driver. Could this also be an indication that there is something wrong with the internals since I have had 4 check engine light warnings (PO442 code which is emissions) in which dealership can not locate the problem.

Checked with a local reputable Chevrolet dealership in Phoenix instead of the inept one in Scottsdale. They took the time to inform me that the C6 corvette with the run flat tires will not activate the Tire Pressure Monitor System dash board light until the pressure drops tp 6 psi from the recommended 30 PSI. In light of the aforementioned, it would be wise to check tire pressure readings with the on-board system which is extremely accurate. Not sure why they set the threshold so low. Want to thank Dad for is inputs regarding Check Engine Light. Chevrolet refuses to take it to a higher level to resolve problem so I will try a different dealership which has trained Corvette mechanics on staff. As a backup, I purchased a On Board Diagnostic Sytem to monitor this problem if they can't resolve this issue. I figure the item failing will eventually permanently fail and allow any dealership to resolve problem. The lesson I learned from these incidents is that the Chevrolet technical support is worthless. I think my dog knows more about cars than these service technicians who's only concern in the morning is what tie to ware.

 

[navy2kcoupe]

I think it is a little disturbing that government motors knows what my air pressure is in my tires. My new yukon with onstar tells me when to change the oil and when there is service required. I was speaking to the on star "Lady" the other day and she new where I was and when I shut the car off. She also told me all engine codes that may appear will automatically be sent to my dealership. I don't know about the rest of you but that is a little more than I am comfortable with. se

They probably have the ability to monitor how fast you're going as well! Big Brother's been here for awhile it seems!
Andy

 

[Pourboire]

A few weeks ago I mentioned that Chevrolet indicated that the air pressure warning system will not activate until tire pressure reaches 6 psi.
Well I can report from experience that this imparted information is false. I had a catastrophic tire failure in one of my Run Free Flat tires. I heard a loud bang out of the passenger rear tires which was plugged only a week before. I turned on the pressure measuring capabilities which the Vet. has and monitored the pressure as I drove home. During this period the pressure warning system activated around 20 psi +/- 2 psi. Not sure when updated info is displayed in the diagnostics. Once again i received incorrect information from Chevrolet service personnel. Fortunately when I bought the car I purchased road hazard insurance from Discount Tire (No better tire company can match their service and prices). In the end the replacement tire cost me $79.00 (cost for new road hazard on tire), which was better than paying out $700.00.

 

[Dad]

Reread your post of 6-14-2011, they did not tell you the system will activate when the pressure reaches 6 PSI . Pressure is to be set a 30 PSI cold, if it drops to 25 or below, 6 pounds, it will activate a warning. The information they gave you was correct.

 

[Pourboire]

Dad, Actually (Steve at courtesy Chevrolet in Phoenix did the research on my inquiry) and stated 6psi not 6 psi below 30 psi. Naturally this did not make sense to me either because the On-Star was activated to report this problem via and e-mail The reason I inquired was that the warning was not coming on when my tire pressure was reading 21 psi when I had a nail in the tire.

 

[NORTY]

The range for TPMS is 24PSI to 42PSI. If your pressures go above or below those thresholds, then you car will go into "ACTIVE HANDLING ACTIVATED" mode. The car won't allow you to do certain things (such as try to pull 1G laterally in a turn.) Individual braking can and will like occur.

One of the 1st things any driver (with TPMS) should do is check your pressures when they're cold. (Of course, cold can be subjective.) Cold is different in Chicago than Sandy Eggo. I prefer 31PSI (rear) @ 60F and 30PSI (front) @ 60F. Then I watch oil pressure, then coolant temp, then oil temp, then coolant temp again. I do this during the 1st 10-15 minutes of driving.

I doubt the service techs wear ties anymore. Too many have been killed or maimed by V-belts and other stuff under the hood over the years. OSHA might have a problem with them wearing ties, loose clothing, jewelry...

Back in the 1970's, While taking an auto shop class in high school, I saw a guy get "drawn in" by a string around his neck (he was wearing a "hoodie.") Just about cut his head off as the string wrapped around a fan blade. He lived but he bled like a stuck pig until the EMT's got there.