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Thanks mendonsy for pointing me to bstevens solution to the TPMS system. I had made an appointment to have the system re-synced to my new wheels / sensors. My Toyota dealer wanted $99.99 for this so I scheduled with a local garage who quoted me $47. When I saw mendony's post with the link to bstevens work around I cancelled my appointment and headed over to Radio Shack. The parts cost me $3.97. I came home and did the job in an hour [I removed the glove compartment box 'cause I value comfort more then time. I turned on the old Tundra and no TPMS light! I saved a minimum of $45 and possibly more. This site has provided me with so many cool ideas! Thanks bstevens! Now can someone figure out a plan to solder together a couple of resistors and diodes together to improve my MPG to 25 or 30?




I know I am going to catch a lot of slack about on this one but as a Service Adviser I don't quite understand wanting to bypass a safety system. Yes, I know it is annoying if there is a bad sensor (blinking light) but I would rather know than be driving around on a low tire, prematurely wearing the tires I spent good money on.

I just switched my wheels to the Tacoma 20" X-SP wheels so I currently have a sensor issue (constantly blinking TPMS light) but I just couldn't bring myself to bypass the system just to make it go off.

Yes, the dealership is expensive at times but did you really pay over 20-30 grand to bypass a safety system? A sensor does not go bad that often. When you change wheels, the sensor doesn't go bad unless the installer messed it up and in that case they can replace it. If they can't replace a sensor they ruined then why are they working on your vehicle to begin with?

Again, I know I am going to catch a lot of slack for speaking against the flow here but I had to add my 2 cents. Everyone here knows me and knows I love to mod as much as the next guy so my opinion isn't against a useful mod, it's against a mod to bypass a safety system. Just like the annoying seatbelt chime. It's not annoying if you put it on...

/end rant
As already mentioned there is no requirement by the FEDS to have these systems. I think that the manufacturers came up with them more in the interest of having another profit center versus a concern for safety. Even when my TPMS was functioning I used tire pressure indicators [from Radio Shack] which told me which tire needed air. Now it will be my TPMS.

Tire Indicator.jpg
 

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there is no requirement by the FEDS to have these systems. I think that the manufacturers came up with them more in the interest of having another profit center versus a concern for safety.
"In the United States, the Firestone recall in the late 1990s (which was linked to more than 100 deaths from rollovers following tire tread-separation), pushed the Clinton administration to legislate the TREAD Act. The Act mandated the use of a suitable TPMS technology in all light motor vehicles (under 10,000 pounds), to help alert drivers of severe under-inflation events. This act affects all light motor vehicles sold after September 1, 2007. Phase-in started in October 2005 at 20%, and reached 100% for models produced after September 2007. In the United States, as of 2008 and the European Union, as of November 1, 2012, all new passenger car models must be equipped with a TPMS."

See full text at Tire-pressure monitoring system

Steve
 

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There are also some states that require TPMS as part of their inspection for all vehicles that came equipped with it. NY started testing them in January as part of the annual state inspection.
You could probably get away with a simulator, but it would need to be a bit more sophisticated.
 

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Thanks Steve - I stand corrected. Here's another bit from your link...

"TPMS are not mandatory, but if a TPMS is fitted, it must comply with the regulation."

Is there a similar statement somewhere with regard to the AIP?

I like these workarounds or bypasses that have been developed but it sounds like it's the "Big House" if they're discovered.
 

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Thanks Steve - I stand corrected. Here's another bit from your link...

"TPMS are not mandatory, but if a TPMS is fitted, it must comply with the regulation."
It helps to maintain context. The actual statement is: "For N1 vehicles, TPMS are not mandatory, but if a TPMS is fitted, it must comply with the regulation."

Vehicle Category N: used for the carriage of goods
N1: having a maximum mass not exceeding 3.5 tonnes (7,700 lb)
N2: having a maximum mass exceeding 3.5 tonnes but not exceeding 12 tonnes (26,000 lb)
N3: having a maximum mass exceeding 12 tonnes

I interpret Category N as commercial vehicles, though "carriage of goods" is kinda ambiguous.

Steve
 

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My '05's light started blinking constantly recently. I figured since it's now 7 years old, and I don't want to dissable the system (I like having it - it's pointed me to a low tire due to a nail at least once or twice now), might as well replace all sensors instead of just the one who's battery died. My truck has a sensor in the spare as well as the main 4, but I thought I'd buy 4 sensors, and then (I thought) have the ECU set so that it ignored the spare. Anyone know if this is possible? Or, do will I be forced to get a replacement TPMS for the spare as well?
Thanks,
-Scott
 

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Yes. Go to Tundra forum. It is at the top of the list right now.
 

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Thank you very much for sharing your expertise. I was in disbelief for the first three minutes. One more very happy modier.
 

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This is awesome, I don't know how this was figured out, but well done indeed. One question if I may though. I don't want to zap anything, so I was wondering if anyone has the Radio Shack part number for the Zener? I found the resistors in my stash, but I would like to be certain that I have the correct diode. Thanks a bunch.

Edit: So the nearest Radio Shack was useless. They just pointed to a wall when I asked about diodes, they are a franchise store. I was in another town today and thought to check their store, a corporate store. I was told that the corporate stores are required to carry everything on the Radio Shack website. When I asked about 12v diodes, the employee walked up to a drawer and handed me these:
 

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About 4 bucks at Radio Shack and this mod worked great. Easy to swap back & forth as I swap wheels on truck. Took two tries as diode package diagram and diode didn't match for proper direction.
 

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I have an '07 Tundra, and I know there are a lot of solutions out there to disable the TPMS light, but I think that I have found a way to trick the computer into believing that everything is working correctly without removing the dash or having to store those stupid sensors in pressurized container in the truck. I bought $5 worth of stuff at Radio Shack and it took me about 30 minutes.

I soldered a 12 volt Zener diode, a 1/4 watt 2.2k ohm resister and a 1/4 watt 1k ohm resister together to look like this. Be careful with the diode to ensure that it is facing the correct way because it only lets the voltage flow one direction.

Behind the glove box is a small grey box with a 12 pin connector to it. You can do this mod without removing the glove box if you don't mind spending some time on your back in the floorboard.

Remove that connector and then on the left side of the connector (the side with the clip) remove the light blue wire (5th one from the top). There is a compression fitting on the side of the connector that you will have to pop out approximately 1mm and then you can use a pin to remove that metal connector out of the plastic harness from the connection side. This is fairly simple to accomplish (hard to explain) but only necessary if you think that you may want to return it to factory operation at some time, otherwise you can clip the light blue wire.

Next step is to connect the resistor end of the series that you soldered together to the light blue wire. Then reconnect the plastic connector to the computer and stick the diode end into the back of the plastic connector so it makes contact with the yellow wire in the top right position.

This sends approximately 4.4 volts from the computer thru the light blue wire to the combination meter to tell the system that there is no fault.

I have had this system on my truck now for about a month and have never seen that stupid light (it doesn't even show up on start-up since it always thinks everything is working perfect). And just to check this theory I swapped it back to factory spec today and the light came right back on...put it back the way I had it and the light went right back out. If anyone needs more pictures or additional info I would be happy to provide it. This fix saved me over $600 for 4 new sensors and the reprograming fee. Hopefully it will help someone else too.[/QUOTE

___________________

MAAAAAAAANY THANX!
Thanx for the solution!
i just finished wiring it according to your example. it worked like a charm.
for those who are wondering if its worth the trouble, i say go for it. Dont doubt.
you dont even have to take anything off to do it either.
i thank God for like you who spend time to share ideas and solutions!
keep up the good work folks, cause people like me need help more often we wish not :)>
 

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So what happens if you don't use the diode and Zener and just cut the blue wire, then connect it to the yellow wire, while leaving the yellow wire in tact? I remember doing something like that on my 08 Tacoma and it worked, don't see why it wouldn't here.
 

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I bypassed the tpms light just by checking my tire pressure with a tire gauge weekly. And if I'm on a long trip, I check them whenever I stop to stretch the legs or fuel up.
 

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Is this still working ? I have spent about 40 bucks today on pvc pipe caps trying to get canister thing pipe kept leaking made one out of iron pipe.light flashes then goes solid, even with cylinder in the pressurized. Got new wheels and tires, tire shop could not get sensors out they cut them out, I don't if the valve stem part being gone messed them up? Tire shop wants 300 buck for new sensors. Not seem like a dumb ass. How do I know the dyoide is going the right way?
 

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If your sensors are damaged, you will need new ones. Buy new ones and have the vehicle programmed for them. It would be a good idea to write down the serial number before you install them.
 

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Is this still working ? I have spent about 40 bucks today on pvc pipe caps trying to get canister thing pipe kept leaking made one out of iron pipe.light flashes then goes solid, even with cylinder in the pressurized. Got new wheels and tires, tire shop could not get sensors out they cut them out, I don't if the valve stem part being gone messed them up? Tire shop wants 300 buck for new sensors. Not seem like a dumb ass. How do I know the dyoide is going the right way?
I'd let the tire shop that wrecked your sensors know that when they get your new ones, you'll pay your bill.
 
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