Tire Pressure Assembly and TPMS repair kit (nut, washer, valve insert, cap) info

[Soda Popinski]

I recently purchased a set of four (4) Subaru Tire Pressure Assembly kits from Harte Subaru in Hartford, CT.

 

Harte Subaru caimed that the Sensors came in a sealed assemby kit with Sensor, Washer, Valve Stem and Valve cap, but no nut. The nut is required to actually hold the sensor to the wheel. The dealer had claimed that there was no part number; I was unable to locate a Subaru specific part number. There is an aftermarket product readily availabe called an AirAware TPMS Service Pack. See Below for part numbers and prices.

 

At least in the 2008 Subaru line, we use what's called a Schrader Tire Pressure Monitoring System (TPMS) which works by direct-read. This means that once the tire pressure falls below 26PSI, the sensor stops sending a signal, and when the TPMS 'brain' stops getting a signal from any of the four (4) sensors on the car, it will turn the light on. This is a solid light, and if any of the 4 sensors are missing alltogether, the light will flash.

 

The Schrader system can be either an aluminum valve stem or a rubber valve stem, except the rubber ones will have a brass band 3/8" thick at top of the rubber stem before the valve cap.

 

I have the alluminum stems on my vehicle so I will explain these.

 

Here's what the assembly looks like when ordered from Subaru:

 

http://i167.photobucket.com/albums/u148/cherrybloom203/legacy%20gt/0524081410.jpg

 

To the lower left of the SEL sticker and barcode, is a small hole (in this picture, it's in the extreme lower left of the picture). This is the antenna.

 

The washer comes pre-inserted on the base of the stem and sensor, which is black. The valve stem is already screwed in and secured (the auminum shaft... the small torx screw is located in the small hole between the sticker and the valve shaft in the picture). The valve cap is a small, grey colored plastic cap.

 

I must state this in bold because this is worth it:

 

Never use metal caps on your valve stems, you run the risk of seizing the caps to the stem, and when you go to remove them, they will snap the stem off because of metal fusion.

 

Inside the valve stem is a removeabe valve insert. Never use anything other than a nickle plated valve insert or it will fuse itself in there, and you can't get air in or out.

 

This brings us to the fact that the SOA kit DOES NOT COME WITH A NUT/SPACER part.

 

Schrader Bridgeport is the name of the company who makes the AirAware kit used for replacement or repair TPMS kits. Here's a picture of the correct kit used for a Subaru with an Aluminum Valve Stem:

 

http://i167.photobucket.com/albums/u148/cherrybloom203/legacy%20gt/0524081410a.jpg

 

Note what comes with in the 20011 kit:

 

A Metal Sleeve/Nut combo. This is a speciaty spacer and nut. You can't just go to the hardware store and buy one. Again, if you use anything other than an auminum nut, you will seize the nut to the valve threaddings and it will snap off.

 

The 20011 kit also comes with a replacement washer, handy to keep around incase one of yours cracks or dries out. The kit aso comes with a replacement plastic cap and a nickle plated valve insert.

 

What the insert does is let you release all the air from the tire by unscrewing it with a special valve removal top, which looks like a pair of tweezers that fit around the sides of the insert push pin. It unscrews in the standard, lefty loosey - righty tightey fassion.

 

There are cheap knockoffs that use steel inserts... you MUST use a nickle plated one, with the RED band.

 

The AirAware repair kit is readily available at MOST aftermarket wheel and tire shops, garrages and should be at Subaru dealers who are smart.

 

The AirAware repair kit part number is 20011 and cost me $8.00 + tax in Connecticut, USA.

 

For a more in-depth look at how the TPMS system works is a thread HERE

 

Also to note: when removing a tire off a rim with a TPMS, always break the bead on the opposite side of wheel, on the same surface as the valve stem. This is so the tire bead doesn't break the sensor off when you go to remove the tire off the wheel.

 

As of 5/22/2008, the price of the TPMS sensor (each) from Subaru of America dealers is $70.88 PER SENSOR. These are vehical specific and they recommend you give them your VIN number when requesting them.

 

Also, the Subaru TPMS system DOES NOT RECOGNIZE where on the vehicle the sensors are located, so rotating does not screw it up. The TPMS access port does not report a location code or the actual tire pressure.

 

If you replace a sensor or a set, you MUST have them re-callibrated to the TPMS computer or they will not be recognized. The TPMS computer can only retain codes for 4 sensors, which stinks because you cannot add one for the spare tire, or a secondary wheel set for winter tires. As of 5/22/2008, the cost to re-cal the sensors is $45 USD in Connecticut.

 

If you are thinking about disabling the TPMS light or not using the sensors at all; note that it is illegal (in the united states) to disable, tamper or bypass the sensor light. By law, no garrage, retailer, wheel reseller or dealership can touch it. Supposedly, the access port cannot do it.

 

P.S> if you wanted to re-cal the wheels yourself, the computer that allows you to do it costs $5000, according to the dealer.

 

If you have the rubber or chrome covered Schrader valve stems, here are your part numbers for the replacement kits (not the sensor):

 

22008 - Chrome (pastic-chrome cap, not metal)

20008 - Rubber (black plastic cap)

 

Common sense: When you bring your car in for service or to a tire shop, or garrage: Remove your valve caps incase they were to lose them. Put them in the cup holder or keep a zip-lock bag in the car handy so you can make sure they get back on there. Over the years I've visited a number of garrages who never put the caps back on.

[jamiesong]

I saw your previous thread and though I would point out that they do exist. I picked some up when I first got my 08 and was shopping for winter wheels tires last fall... I don't remember the cost... but as expected from a local dealership it was a bit excessive. Pretty close to the cost of the kit you found... Just thought I'd put this out there.

 

http://i243.photobucket.com/albums/ff157/jg7734/0526081533.jpg

[yakker]

Great. Another safety gizmo forced on the public because of fat, lazy americans.

[Soda Popinski]

An update: yet to confirm. The aftermarket sensor repair kit did NOT work on my new rims, because the internal threadding inside the nut spacer doesn't come all the way down to the edge. It stops about 1/8" shy of grabbing the subaru oem valve stem when mounted. I'm going to order some sensor nut valve's (pictured above) and compare.

 

Will keep this thread posted.

[CzarDestructo]

I recently had to have one of these replaced by a local tire shop. They claimed they could re-program the car computer in shop. They did something in the car interior, some sort of button combination on the dash. They told me after I turned the car on and off a few times the computer would accept the new combination of sensors. Needless to say this didn't work and I really don't feel like spending another $45 (on top of the $120 to replace the damn thing) to have them change a single variable in the computer.

 

Does anyone have a service manual or know this button combination so that I can give it another shot?

[js516]

There isn't any button combination. I think the dude in the tireshop has been playing too much Soul Caliber IV.

 

You need Subaru's diagnostic tool to place the TPMS system into learning mode and then using a TPM tool to trigger each transmitter in sequence and have it send out its id.

 

I'm hoping someone somewhere can grab the messages that get exchanged between the select monitor tool and ECU/TPMS. If we have the protocol, then its not that big of an effort to write a program to do the same thing using a USB/Serial type adapter.

[LGT Dave]

There isn't any button combination. I think the dude in the tireshop has been playing too much Soul Caliber IV.

 

You need Subaru's diagnostic tool to place the TPMS system into learning mode and then using a TPM tool to trigger each transmitter in sequence and have it send out its id.

 

I'm hoping someone somewhere can grab the messages that get exchanged between the select monitor tool and ECU/TPMS. If we have the protocol, then its not that big of an effort to write a program to do the same thing using a USB/Serial type adapter.

 

+1

 

Only the dealer can reset the TPMS system at this time. There are other car manufacturers that make it so that you can do this yourself, but Subaru decided not to make that possible.

[CzarDestructo]

You need Subaru's diagnostic tool to place the TPMS system into learning mode and b] then using a TPM tool to trigger each transmitter in sequence and have it send out its id. [/b]

 

Are you implying that each sensor needs to be triggered physically or can everything be done without having to dismount the tire again?

[js516]

Partial yes, each sensor has to be triggered individually, in sequence. The TPMS tool is a device that you point at the valve sticking out of the wheel, and hit a button to send the sensor an RF signal telling it to send its id. Other TPMS sensors use a large donut shaped magnet, but IIRC thats not the type we have. You do not need to unmount the tire.

 

http://www.artsautomotive.com/TPMS.htm

[CzarDestructo]

Big thanks for the insight. It's making me more and more irritated that these things had to be installed at all. I think after I eat up these stock tires I'm not going to bother replacing these damn things. Not worth the price.

[BradyCat]

I'm shopping for a set of winter wheels and tires, so I phoned up the dealer and asked how much a new set of TPMS's would cost for my new rims as well as the cost of 'recoding' them. They said that my rims do not have sensors in them and that the sensors are housed in the differential and that they work on wheel speed and not actual tire pressure or something. He said I would be able to put on new rims without having to buy new sensors and the monitor would not have to be recoded. I don't suppose the '09's are any different then previous years? Is my dealer talking out of his -ss or what?

[ilh]

If the Canadian cars are like the US cars your dealer is an idiot. The US cars certainly have sensors inside each tire. Does Canada have the TPMS requirement that the US has?

[kirbwrx]

can anyone tell me if it is necessary to rebuild your tpms when you swap tires? i just came from discount tire and he told me i needed to rebuild them everytime i changed my tires...sounded like bs to me so i walked, didnt feel like paying $40 for something i didnt need and he was pissing me off being so pushy about it

[Mr. Sinister]

can anyone tell me if it is necessary to rebuild your tpms when you swap tires? i just came from discount tire and he told me i needed to rebuild them everytime i changed my tires...sounded like bs to me so i walked, didnt feel like paying $40 for something i didnt need and he was pissing me off being so pushy about it

 

He fed you BS. I just got a new set from Discount Tire as well and I specifically asked if I needed the rebuild and the salesguy said no. He said he would have told me if I needed to but since the car only had ~5K miles on it, I wouldn't need to.

[DrCloud]

[The dealer] said that my [09] rims do not have sensors in them...

There are TPMS systems that don't use sensors, but 09 Subarus still use the same sensors as the 07s and 08s, according to TireRack, at least. I tend to trust them.

 

can anyone tell me if it is necessary to rebuild your tpms when you swap tires?

Not unless the installer has crushed a sensor during the tire de-mounting/mounting process. TPMS sensor batteries are designed to last 5+ years.

 

And previous posts are right -- to this point, only Subaru dealers have the tool to reprogram a system for new sensors. We finally had it done (to sensors supplied by TireRack), and it worked fine. My wallet was sore, but it worked. HPH

[NutBucket]

Great. Another safety gizmo forced on the public because of fat, lazy americans.

Bingo. Happy I don't have these.

 

On my dad's Tacoma, there's a sensor on the spare as well so you're forced to pull it out from under the bed and keep it inflated. Not a bad idea, just very inconvenient.

 

But, at least his truck has a button under the dash for the TPMS...haven't read the manual but likely to recalibate the system

[rymac320]

I recently purchased a set of four (4) Subaru Tire Pressure Assembly kits from Harte Subaru in Hartford, CT.

 

I must state this in bold because this is worth it:

 

Never use metal caps on your valve stems, you run the risk of seizing the caps to the stem, and when you go to remove them, they will snap the stem off because of metal fusion.

 

 

+1 ... I had no idea the metal Subaru star caps would seize on like that - i snapped one of my metal valve stems yesterday while trying to get it off. (See pic - note the inside of the cap is the part of the stem that seized.)

 

That tire has been loosing pressure consistently for the past 3 months, even though the dealer has 'fixed' the leaky valve stem 3 times. If they had actually fixed it, I never would've had to put air in it, and in turn, never broken the valve stem!

 

So rather than drive around with the donut, I'm friendly with a garage across the street from work, and they just put in a rubber valve stem for nothing until my appointment with the dealer.

 

During this I also discovered that the other 3 are also seized on. So, will the TMPS sensors be covered under my warranty? I bought the car new from the same dealer 15 months ago - its a 2008 with 26,000. The caps are Subaru parts that the dealer even sells.

[LegacyMUN2k6]

I hope there covered, i have one tire that loses air. Have to fill up with a air compressor every two dys.

[CapnJack]

Wish I would have seen this thread two weeks ago. I ordered another set of sensors for my summer wheels and found out the sensors did not come with nuts. The parts person and I did find the nuts from Subaru however. They were $1.68 each.

 

Subaru Part Number is 902860004 NUT VALVE 10V2

[Aczwild]

Soda Pop, here's a question for you. The sensors you have pictured are for a 2007 Legacy, not "for your 2008" (they are different). Did those sensors work with your 2008 GT, or did you have to get the 2008 sensors?

 

The reason I ask is because I have a set of 2008 sensors and my stupid dealer has told me that they wont work on my '07 (I really dont trust them much any more). Before I install them I want to know if you had a problem, or if anyone with an '06-'07 GT has used the 2008 version

[dmanaenk]

^ 07 sensors work fine in my 08, so I'm almost sure reverse would be true.

[amp583]

Hell. Mine snapped to half its length - basically the valve cap has some threaded stem in it but theres enough to get some air in and likewise the air pin is still there...

 

Do i need a new sensor or can i fix it with the AirAware 20011 kit?

 

 

 

 

+1 ... I had no idea the metal Subaru star caps would seize on like that - i snapped one of my metal valve stems yesterday while trying to get it off. (See pic - note the inside of the cap is the part of the stem that seized.)

 

That tire has been loosing pressure consistently for the past 3 months, even though the dealer has 'fixed' the leaky valve stem 3 times. If they had actually fixed it, I never would've had to put air in it, and in turn, never broken the valve stem!

 

So rather than drive around with the donut, I'm friendly with a garage across the street from work, and they just put in a rubber valve stem for nothing until my appointment with the dealer.

 

During this I also discovered that the other 3 are also seized on. So, will the TMPS sensors be covered under my warranty? I bought the car new from the same dealer 15 months ago - its a 2008 with 26,000. The caps are Subaru parts that the dealer even sells.