Tpms

Ok so I'm on my second set of aftermarket wheels for my 07 LGT and with both sets my tire pressure light comes on after driving for a couple miles and its not the usual constant light, its a steady blink every 15 seconds. With both sets I made sure I got the TPMS put in the wheel. And this winter when I put my stock wheels on, I had no problem. Whats the deal? Ever happen to anyone else?

So you have a seperate set of tpm sensors for each set of wheels?? If so it sounds like the one set is not calibrated correctly for your car. I believe they use a frequency to communicate with the car.

Correct...and the system will only hold 4 sensors at a time.

Ok so I'm on my second set of aftermarket wheels for my 07 LGT and with both sets my tire pressure light comes on after driving for a couple miles and its not the usual constant light, its a steady blink every 15 seconds. With both sets I made sure I got the TPMS put in the wheel. And this winter when I put my stock wheels on, I had no problem. Whats the deal? Ever happen to anyone else?

 

You have to take the car to the dealer and have them register the new sensors with the system. Like Opie said, the unit can only have 4 sensors registered with it at a time, so you have to reset the system each time you put a new set of wheels on the car (once when you put on your aftermarket wheels and once more when you put the stock wheels back on). Subaru did not include a way to do this yourself. It sucks, but that's pretty much just the way it is.

Hey thanks for the great info guys. I havent had a good reason to head down to the stealdership in a while.

You would have thoght they'd have been nice enough to include a graphic of which tire is low when the light does come on. Happened on my wife's OB and it was of course the 4th tire I tried.

Is it okay to keep driving with that light blinking

If you take out the "m", you have TPS. TPS reports, anybody? Heh. Nevermind.

Is it okay to keep driving with that light blinking

 

It won't hurt anything, just means the system's not happy.

 

Its in the manual but I think flashing indicates a probelm with the system (as in no sensors detected) but steady on indicates a problem with the actual pressure its reading.

 

Once the sensors are registered, if it flashes it needs attention.

 

On my wife's car the light went on when one of the tires hit 28 lbs or so.

Ok so I appologize for not looking for my manual but...

 

I simply upped the pressure and mine blinks.

 

Anyone know the pressure range these things are happiest at?

A solid light means you have one or more tires that are low (less than about 27 lbs I think). Blinking means there is a problem with the system. According to the service manuals, the possible causes of a blinking TPMS light are: air pressure sensor malfunction, air pressure sensor is out of battery, tire pressure monitoring control module is faulty, or defective vehicle harness.

According to my dealer, they can program the trip points with the Subaru select monitor or whatever tool they use. I don't know if there's an "over" high range as well.

 

FWIW - I read an article that said metal valve stem caps can screw up the signal to the computer.

It may be that certain tire centers can program the ECU (or whatever the controller for the TPMS is) for the sensors as well. If your dealer is a long drive, try phoning around to Goodyear and Firestone places. HPH

A solid light means you have one or more tires that are low (less than about 27 lbs I think).

 

I've learned how sensitive these things are. When traveling up or down the mountain in the winter, the light will turn on or off, respectively. We actually had the temps dip into the 40s one night here recently, and that sent the light on. I checked the pressure in all 4 tires with only one being around 30#; however, upping the pressure turned off the light. Sheesh!

Is there anyway of just getting rid of the entire system? dont care for it too much, i can check my own tire pressure. I dont want the hassle of going to the dealer everytime i change my rims back for winter or summer.

I don't know. Its federally mandated, I think, so intentionally disabling it may be a no no.

 

On the other hand I don't know of any test for it at inspection time, unless they check for a code in the ECU when they hook up to the CAN bus.

 

The simplest way is to probably pop the bulb from the cluster, but I don't think I'd be wanting to take that cluster out just for that.

 

Around here at least one tire shop can reprogram the system, Sullivan tire. One of the guys there was complaining about how expensive the system was, somewhere around 5k I think he said.

 

If you rotate your tires at all, you should get the system reprogrammed then as well, although since Subaru doesn't provide an indication to me of which tire is low, as long as the computer is happy I don't care where it thinks the tires are.

 

BTW - my dealer charged me about $25 for reprogramming the sensors.