Service TPM light

[RFG]

Just started. Only seems to happen at night after work. When its sub 20 degrees. Will cold effect the system?

 

[IISPEEDYII]

Yeah, it will effect the batteries. Mine has said service tpm since a month after I bought the car, such a useless feature.

 

[Pappibri]

Mine tends to do that sometimes when the temps dip below 20*. I agree, a worthless feature. I can tell by driving my rig if a tire is low. But I guess some people need a machine to tell them how to do everything.:gaah:

 

[08H3]

On a related note, one of my sensors is reading intermittently. I'm sure it's low battery. Is there a way to check and see which one it is?

 

[IISPEEDYII]

On a related note, one of my sensors is reading intermittently. I'm sure it's low battery. Is there a way to check and see which one it is?

Yes, I believe if you try to re sync the system you can figure it out by finding out which one doesn't sync. The instructions are in the owners manual. The one that is dead, or not currently working will not sync and the horn won't beep then.

 

[RFG]

Thanks for the quick replies. I carry a tire pressure gauge in all my cars.

 

[4speedfunk]

I find electrical tape over the DIC helps fix this.

 

[08H3]

Ha ha...if I subscribed to that method, I'd have about a dozen pieces of tape all over the dash.

 

[f5moab]

What is the exact message on the DIC? If it says LOW TIRE, one or more of your tires have dropped below the calibration of the sensor. If it says SERV TPM there is a problem with the system.

If your LOW TIRE warning comes on when you first start the vehicle and goes off after driving a few miles chances are one or more of your tires are low. Since the driving of the tire warms it up, increasing the tire pressure.

I hope you all understand that as temperature drops, air pressure inside the tires drops at a rate of 1 lb for every 10 degrees, and when the tires warm up, the pressure goes up 1 lbs for every 10 degrees increase in temp.

That's why, if the tires are at 35 psi on a nice 80 degree day, they will be at 30 on a cool 30 degree day. So if the sensors are set to turn on the light at 32 psi, the light will come on after the vehicle sits for a while. However once you start driving the vehicle and the tire warms up by 30-40 degrees, the tire pressure just went up by 3-4 lbs going above the 32 psi threshold.

And with large air volume tires like that used on a H3 or other truck it is next to impossible to tell if they dropped five pounds if all four have dropped. On small air volume tires like used on Vettes, sure, there is only an inch of rubber between the rim and the road, not four or five inches.

And the only way COLD affects the system is by the air pressure drop in cold weather. Sensors use lithium batteries so the temps need to drop to around 40 below to affect the batteries.

And low, high or normal tire pressures do not add any strain on the sensor or batteries. Regardless of the temps or the pressure inside the tire, the sensors will send a signal at set time while rolling or less when sitting still for a set period of time.

Oh, and just remember, it was the US government that required these sensors, it was not the car/truck manufacturers.

 

[06 H3]

On the topic of "useless sensors" I work at a tire shop and you wouldnt believe how many people NEED these sensors. Guys, People are ****in stupid, I hate to sound mean but we have people coming in with CEL saying the CEL means I need new tires or when the TPMS light goes on then they think that means the car is telling them its time for a rotation and balance. If it wasnt for the TPMS light people will drive tires with 10lbs of air in them. Its sad.

 

[4speedfunk]

So true. I've been driving around for months with my "OIL CHANGE" message scrolling past. I'm getting pretty good at ignoring the DIC. Perhaps I should sit down at the CAD and draw up a plate that covers up everything except the tach, speedo, and fuel gauge? I could laser cut them from brushed stainless, and screw them to instrument cluster. That way I could finally remember what it means to actually DRIVE a car again!

 

[USMC_TOP]

Do it! I would pay money for one of those!

 

[IISPEEDYII]

This is too funny

 

[cgalpha08]

lol i do agree about the TPMS light, heck if it looks low, it is probably low, I check my tires at-least once a week.

As far as the CEL, yea its annoying when an 02 sensor is triggering it and it doesn't go away, and yea half the time you can hear it when something is majorly wrong with a drive-train component. However it is nice to know when something bad is going on and catch it before its too late.

The oil change message is just dumb. An oil pressure gauge would be nice to have along with a trans temp gauge (i know the scan-gauge offers some of these but im talking about a permanent gauge)

Currently my CEl is on for 02 sensors or something like that, im not really too concerned with it and will change them whenever I get around to it.

 

[digglesworth]

Just push the little reset button on the cluster. The message will come on about 5 miles down the road. Push the reset again and it won't come on anymore on that trip. Not sure if a failing sensor will trigger constant warnings but I dont have sensors. this is how I deal with it. Pushing the reset button twice on every drive. Unless it's less than 5 mile trips. Lol.

 

[f5moab]

On the topic of "useless sensors" I work at a tire shop and you wouldnt believe how many people NEED these sensors. Guys, People are ****in stupid, I hate to sound mean but we have people coming in with CEL saying the CEL means I need new tires or when the TPMS light goes on then they think that means the car is telling them its time for a rotation and balance. If it wasnt for the TPMS light people will drive tires with 10lbs of air in them. Its sad.

Before the system was mandated, the NHTSA did an extensive survey of actual drivers on the roads in about 10 states. Over 85% of the people had incorrect air pressures in their tires. And when the system was first released, the lineup at the dealers on a cold morning would have been funny if not for the dealer technicians adding air to the tires. Most people do not relate air temps to air pressure.

And yes, people are really stupid.

I have run with that message in the DIC and light for almost four years. I guess if I ever really have a flat tire it will be a big surprise. But I'm pretty knowledgeable when it comes to vehicles, and vehicle tires, but I'll be damned if I can tell that my tires are 10 psi lower than recommended by looking at them.

 

[Gunner_45]

 

[Airborne]

I find electrical tape over the DIC helps fix this.

The sh!t he says never gets old. Keep it coming CJ.

 

[chaos254]

On the topic of "useless sensors" I work at a tire shop and you wouldnt believe how many people NEED these sensors. Guys, People are ****in stupid, I hate to sound mean but we have people coming in with CEL saying the CEL means I need new tires or when the TPMS light goes on then they think that means the car is telling them its time for a rotation and balance. If it wasnt for the TPMS light people will drive tires with 10lbs of air in them. Its sad.

I feel your pain lol. I work at a Ford dealer and we get at bunch of people everyday that come in freaking out about their tire lights being on. Always the worst in the spring and fall.

Most people know nothing about cars so they just drive until a light comes on telling them they need service. It's scary to think about how many people are driving around with no brakes, bald tires, etc.

 

[Panzer07]

I feel your pain lol. I work at a Ford dealer and we get at bunch of people everyday that come in freaking out about their tire lights being on. Always the worst in the spring and fall.

Most people know nothing about cars so they just drive until a light comes on telling them they need service. It's scary to think about how many people are driving around with no brakes, bald tires, etc.

I agree I was one of them people's that new nothing about cars...when I first got my H3 but after a week I actually sat down and read the user manual...I was amazed of how many pages the manual actually has about seat belts and it's safe and operation...once I got done I had all my questions answer and new what each button and light mean or do. Needless to say my manual ended up with a bunch of sticky notes of what I consider important.XP.

Torres

 

[RFG]

I just rotated the tires. All at 35#. So. I'm going with temperature.

 

[Best4x4]

I'm not sure how the GM tire sensors work, but I know some TPMS can be tricked by making a PVC tube with the sensors inside of them. Then you add a valve stem and pump up the PVC tube to like 40PSI and you can run aftermarket rims with no TPMS sensors and you don't get any faults.

On my F150 I just covered the stupid LED under the gauge cluster skin, and called it a day, but since we have the DIC it's not that simple lol. You could cover the (_!_) LED on our H3's and then when it freaks out just hit the tripometer button to clear it.

 

[4speedfunk]

H3 sensors need centrifugal force to work.

 

[4speedfunk]

Electrical tape over the warning light works good too!

 

[rsc]

TPMS is the most worthless requirement. In the south we get big temperature fluctuations. Last weekend I got up to ice on my tent but it was 80 in the afternoon. How do you set the system for psi variations of 5 or 6 degrees just due to air temperature? And on top of that, you have to unmount the tire to change out dead or dying batteries that give no signal in the morning but work in the afternoon.