Low Tire Pressure Warning Light
 

Hi All

You've been helpful before...here's hoping you can help again!

My "Low Tire Pressure" light has been on my dash for a day. My tires are fully inflated. They are factory No2, but I topped up with air from the gas station today to 37 psi ( the recommended amount on the inside of the door). I called the dealership and they said drive for 20 minutes over 50 km. Did that...nothing...

I recently had a similar issue with an oil change light...and you guys knew a great "reset". Any special magic reset for this dilemma?

one mroe little note...I'm in London...the place with all the snow recently...any chance the cold weather has afected anything in the tire pressure sensor? Just a thought.

Happy Jeepin'

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Re: Low Tire Pressure Warning Light
 

Could be the snow up to the window ledges. lol I'm from outside Sarnia and glad of it today!

Re: Low Tire Pressure Warning Light
 

The weather does mess with these sensors , if your tires are at the right psi , then try to ignore it and it should go out . Mine go on and off with the weather changes .

Re: Low Tire Pressure Warning Light
 

Hiya,
ff. Filled with summer air?

Re: Low Tire Pressure Warning Light
 

I don't have all those new gadgets on my tj, but possible cud be snow has gotten around the senor and its frozen, clean around the area of it, if you remember what the tire pressure was b/4 u put air in, try going back to it, or if all else fails then disconnect the battery for say 30 mins then reconnect supposedly it resets your computor.. your going to have to reset your stations on the radio..hate that..lol

Re: Low Tire Pressure Warning Light
 

If it's the jeep in your sig, it's still under warranty, take it in and tell them to fix it. There have been all kinds of problems with these tpms. Or just put a piece of electric tape over the light.

Re: Low Tire Pressure Warning Light
 

Have you changed your tires recently?
Old fart is right it's under warranty bring it in. The part about the tape over the light well that's your choice but for me after spending over 30g's on a JKU I not putting a piece is tape over anything to cover it up, Sorry oldfart just my opinion.
I have to say I have not had much problem myself with the TPMS I did however get suck in some mud once and broke one leaving me stuck and with a flat. But that is what a winch is for right? I'm a tech at a dealership I have however had a few clients who have problems. I once spent 2 1/2hrs trying to turn the light off and never did she had to go to work and needed her Jeep back. Most of the time is is very simple, adjust air and drive the light goes off.

Re: Low Tire Pressure Warning Light
 

Did any body try putting up to 40psi and then dropping to 37psi? the sensor may need to be slightly over pressured to reset it then reduce the pressure to the recommended setting.

Re: Low Tire Pressure Warning Light
 

Thanks all for the tips (even the elec tape...you meant well). After I posted I headed off down the 401 to less snowy roads. I got to Woodstock-ish and all of a sudden the light went off, and has not come back on (to TO and back). Thinking it had something to do with warming the tires up thoughourly. Yes indeed, I have "summer air" except it's more like "Summer No2".

If it happens again...damn right Im heading to the dealership...warranty in hand.

Happy Jeepin'

Re: Low Tire Pressure Warning Light
 

Was temp related for me. Temp hit -30 light on. Drove to heated garage, light out. Next morning after about 20'mins driving light was on.

Re: Low Tire Pressure Warning Light
 

Cold weather decreases pressure, thats all it sounds like to me.

Re: Low Tire Pressure Warning Light
 

Possible for sure. Not true always. My viar supplied dial gauge showed I put 37 lbs in all 5 tires, 5 lbs more than I usually run. In my case I think it was the cold.

Re: Low Tire Pressure Warning Light
 

First off I support the warranty reccomendations, for sure.

My 0.50cets...on my 08JKU This light has come on twice, usually when there's a good change in temp. The solution has always been drive to the dealer and have them touch up capacity of the tires with nitrogen. Each time it didn't take much, I think the sensor is pretty sesative. I just wonder how it works, is it wireless? Huhhh!

Re: Low Tire Pressure Warning Light
 

mine is on as of this morning... -20 here the coldest morning yet... gonna give it a bit before I go to the dealership about it.

Re: Low Tire Pressure Warning Light
 

checked the tire pressure and all 5 were down 3-4lbs so i topped them up and ta da no more light yeah!

Re: Low Tire Pressure Warning Light
 

note: soon after I got my Jeep last winter I had the same problem with this stupid light... make sure the spare is also at 37, it has a sensor as well. Now I dont even notice the light as it is on 24/7 cause of the 35s :)

Re: Low Tire Pressure Warning Light
 

Thanks Jenna , good call on the spare , always forget about it till it is needed .

Re: Low Tire Pressure Warning Light
 

The spare tire is "Not an Active Tire" and therefore will not activate the TPM warning lamp.
The reason for this is if you did have a flat and change it with the spare. After 10min of driving above 25km/h the system will automatically update and the TPM warning lamp will extinguish. Now the system is ready to warn you of another tire pressure problem should it arise.
Recap the spare will not turn on the light should it(the spare) go flat, on this model.
In the pass on some other models the spare would turn on the light but it would normally tell you the the spare tire is the one that is low.

Re: Low Tire Pressure Warning Light
 

if you say so. I just know that on my 2009 JK the only tire that was below the recommended setting was the spare and once I filled 'er up the light went away. By process of elimination I determined that the spare was the problem and the TPMS was the same as the other 4 tires. I dunno tho... I'm just a girl :)

Re: Low Tire Pressure Warning Light
 

LOL " I'm just a girl :)" Girls can beat us guys any day in any sport or hobby. There is a woman(Isabel) in my other hobby, R/C airplanes IMAC contests. That kicks OUR ASSES every time we compete against her, so don't give me that.
I didn't want to come off rude, sorry if I did. I just wanted to clarify that spare is not an active tire. I am 99.9% sure but just for argument sakes I'll deflate my spare before going to work tomorrow morning and double check.
The reason I know is because I got a flat in the bush once and the light came on. After I changed it with the spare and drove the 10min above 25km/h it turned off even thought the spare tire was flat. the Key to this whole thing is "driving 10min above 25km/h"

Re: Low Tire Pressure Warning Light
 

If you take the tires off vehicle and leave in garage, the sensors will set off light when you pull into garage. In this case I'd say all 5 are inactive but computor still picks up sensors every time drive into garage.

Re: Low Tire Pressure Warning Light
 

Hello
So I aired down my spare to 13psi and drove to work today. No TPM light came on. We all should check our spare ever so often because, it may go flat and we wouldn't know. And if that time comes and we need it :O it will not be a great spare :)
Unless you have an onboard compressor.

Re: Low Tire Pressure Warning Light
 

Hey JeepTechO!!!!!!!O

First thanks for the clarification on the 5th wheel not having a sensor. Huh. Cost savings perhase?? You would think it should be (monitored) a flat spare when you need it will spoil the buffet line every time. :)

Do you know how these sensors report back to the computer? I have yet to figure that one out.
Thanks

Re: Low Tire Pressure Warning Light
 

Judging by the "important notes reguarding vehicles which come equiped with TPMS", that are listed under the rims, on TireRack's website, the sensors are emitting a radio signal similar to how a cordless phone communicates to its base station. They list 315mhz as the frequency a Jeep JK's sensors operate on, but that could just be the univeral frequency the aftermarket makers, (who provide the part to OEM) use.

Re: Low Tire Pressure Warning Light
 

Hello Jeepminded
There is a TPM sensor on the spare wheel. it is just not transmitting a signal while the vehicle is driving.
On vehicles equipped with Tire Pressure Monitoring System, one tire pressure sensor (6) is mounted to each wheel in place of the traditional tire valve stem. Each sensor has an internal battery that lasts up to 10 years. The TPM system operates on a 315 MHz radio frequency(RF). An RF signals of 315Mhz is transmitted by each of the vehicle's active tire pressure sensors(the spare tires TPM sensor is in active) to the WIRELESS CONTROL MODULE (WCM) The WCM communicates with the module(cluster) that controls the "TPM telltale lamp", via the vehicle bus system. Upon detection of a warning or fault condition, the WCM will send a request to illuminate or flash the yellow TPM telltale. Also, upon detection of a warning or fault condition, the display module will send a request to sound the "chime". A chime will only be requested once per ignition cycle per warning or fault condition detected.

Re: Low Tire Pressure Warning Light
 

Hi JeepTech0!!!!!!!0

Thanks very much for your detailed post on how the sensors work.

You are speakng my language (RF) it's my profession. Battery operated transmitters in your valves, cool! Make sense the spare has one, just not active as you say. Means I will now make sure I check it at lease once per month.

Re: Low Tire Pressure Warning Light
 

Darn send button got in the way again....thanks also to Topbanana for answering my question.

Re: Low Tire Pressure Warning Light
 

Now if we just knew where they hide the WCM, we could disable the sucker and everybody's problems would go away. Back to checking tires the old fashion way, with a tire guage!

Re: Low Tire Pressure Warning Light
 

Nothing beats a accurate tire guage.

Something else comes to mind....since each tire has its own RF transmitter, wouldn't it be kinda cool to have the data from each sensor conveted into real time air pressure per tire, and on a display showing all 4 corners....could even add the 5th tire out back. The dash display wouldn't do, it would have to be a seperate screen or something. Hmmm.

Re: Low Tire Pressure Warning Light
 

Some Jeep models do this, Grand Cherokee is one of them. could be others.

Re: Low Tire Pressure Warning Light
 

this sounds like ur best bet . i had the same thing and i over inflated and droped it and it was off before i got off my street. other wise u probley have a bad sensor... good luck

Re: Low Tire Pressure Warning Light
 

Hey, if we're wishin', how bout a GPS with a designated BEER STORE button, that immediately pulls up directions to the nearest one (or LCBO as default)! lol

Re: Low Tire Pressure Warning Light
 

I have a 2010 mountain edition. The tps light came on 1 week after bringing the jeep home. I read up on this problem in other forums. I tried topping up the tires to 35 lb all around, no change at all.
You need to put 37 lb in all of the tires, spare included. The tps on the jk is a dumb sensor, and will not tell you which tire is low. I drove 20 km after putting the air in (I have nitrogen, and putting regular air in with it is fine) and the sensor went out.
Nitrogen is a waste of money.

Re: Low Tire Pressure Warning Light
 

Mever mind....double answer.

Re: Low Tire Pressure Warning Light
 

it's got to do with the outside temp. The owners manual even mentions it. Mine has been on for approx 2 days now, i figure it will go away as soon as it warms up a bit. i'm in Ottawa.

Re: Low Tire Pressure Warning Light
 

Well, i must say i'm going to check my spare tire tonight. My Tire pressure warning light is still on.

Re: Low Tire Pressure Warning Light
 

i had the same alarm at 30 psi topped up with air to 37 psi (door spec) and the alarm went away.
Then the dealership evacuated the air/nitorgen and replaced with nitrogen and i have no alarms ,so take yours back for a fix

Re: Low Tire Pressure Warning Light
 

n02 or 02 makes no difference. filling all tires up to 37PSI should have fixed it alone. 2008 came with no spare TPMS. if 2010 actually does that is good. I wonder if I just get another sensor whether the jeep will monitor that as well? i really dont know how the system works.

can anyone explain. is there designated transponders tpms programmed into the body module? if you park beside another jeep will your jeep monitor another jeep, LOL??.