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Tire air pressure sensor

Two days ago I had new tires put on my 2007 Toyota Highlanders and since that time my air pressure sensor light keeps coming on. The tires are the right size, I checked in the owners manual. I’ve taken it back to the shop that put on the tires twice. The first time they told me the spare was low on air. the second time they told me the batteries in the air pressure sensors are dying and need to be replaced. I thought that sounded like a lame excuse so left the shop and called the Toyota Dealer and asked if the air pressure sensors have batteries. The service department at the Toyota dealer laughed and said no, they run off the car’s battery. I called the shop back to tell them I was very disappointed and unhappy that they tried to sell me something that doesn’t exist and they stood by the batteries in the sensors story and claimed they would show them to me if I would come back to the shop. Who should I believe? Has anyone ever heard of replacing the batteries in tire air pressure sensors? Thanks for your feedback.

Normally the sensor is replaced when the battery goes dead. The battery is under a layer of epoxy inside the sensor.

“Keeps coming on”, is the warning light always on? Check the position of the main/2nd switch under the glove box.

Make sure the tires are inflatted to the proper pressure. Under the dash on right side of the steering column locate the diagnostic connector. Next to the connector is a button to reset the TPM system. Press the button and then drive the vehicle to see if that turns the light off.

Tester

It depends what type is used on yoru car. Some of these tire pressure monitoring systems simply monitor the wheel speed, the idea being that a flat tire being slightly smaller will rotate at a higher speed than a fully inflated tire, and other systems actually monitor the tire pressure using a battery powered sensor inside the wheel. If your car uses the latter type, then it could be a sensor battery problem. To find out which kind you have, you might give Google a try.

Here’s some general info on the subject:

" There are many different [tire pressure] solutions but all of them have to face the problems of limited battery lifetime and exposure to tough environments. "

Thanks No the light was not on before I had the tires replaced and when it came on, I checked air pressure and reset switch under the dash. It came on again. Took it to the shop, they reset it and it came on again. then they told me it was the batteries in the snesors

I just looked it up, the 2007 Highlander doesn’t have tire pressure sensors.

You must press the reset button untill the warning light blinks three times, then when driven the system will reset. It takes 30 to 60 minutes to complete.

From a Toyota bulletin;

“NOTE:
Depending on the vehicle owner’s driving patterns, habits, and trip duration,
initialization of the TPWS may take a significant amount of driving, with several trips,
to complete initialization. For this reason, the initialization should be completed by
the customer during normal driving conditions.”

Well? They may have damaged the sensor(s) when removing the tire(s).

When breaking the bead of the tire from the wheel it has to be done so that the tire bead doesn’t strike the TPM sensor or it can damage the sensor. This is one of those things where no matter how careful you are sometimes the bead breaks and it strikes the sensor. Some shops will own up to this and offer to replace the sensors for their cost. And some shops will deny any fault and charge for both parts and labor to replace the sensors.

Tester

http://www.carid.com/2007-toyota-highlander-tpms-sensors/oro-tek-tpms-sensors-1303186.html

http://www.ehow.com/how-does_4928738_tire-pressure-warning-system-works.html

Tester

This is the first page of the bulletin I was referring to.
This vehicle has an indirect tire pressure monitor.

That was the year TPM systems became manditory on all vehicles. So in some instances about 25% of the vehicles manufactured didn’t have direct TPM systems. But what are the odds that this vehicle has the non-direct TPM system?

Afterall, the first thing you have to do is look at is the compliant. Because if you deny that, then you’ll never figure it out.

Tester

In 2007 TPM systems were required on cars and trucks. This is the first vehicle that I am aware of 2007 and up that is an indirect system. Toyota indirect systems can be a pain to reset.

The OP must look at the vehicle, a metal valve stem indicates a tire pressure sensor. A rubber valve stem indicates no sensor or an indirect system.

Oh, I don’t know. I’ve got one car with the metal valves and I’ll guarantee it has sensors in the wheel. It resets by driving over 20 mph for about 30 seconds. The other has rubber stems and I’ll guarantee that has sensors in the wheels too. That one you reset by a key on type procedure and raise or lower the air pressure until the horn honks. I can’t believe either of these is reading the revolutions of the tires to determine the pressure since I’ll adjust the pressure in the garage and the readings change.

At any rate, I think the guy was saying the sensor batteries are worn out-evidently they’re only good for 5-7 years (or they were damaged when the tires were replaced). In either case, its buy four new sensors for $200 plus and have them replaced. I’ve had a tire and all four tires replaced on the two different cars and never had a problem myself though.

the tire sensors do have batterys in them and they our not serviceable

Did you check the spare? They might have taken one of your old tires to use as a spare and the spare is connected to the sensor, too. My Rav4 did that a lot until we figured out it was the spare. Now I have a Highlander and it does the same thing.

I agree with @Nevada_545
The earlier systems were such a pain, even the dealers were frustrated fixing them. On an 07, I would live with the light on and drive with an air gauge like I always have. Been doing that for the last 5 years with my truck that started acting the same way. You can spend lots of money to make the light go out and end up back at square one in no time flat.

I am pretty sure that the sensors actually operate from the air pressure, in my '09 Caravan. The light will come on sometimmes when the temp is down around 18 degrees and go out if the temp gets above around 25 or so.

@EllyEllis your car is newer.
TPMS had already been required for a few years.
The poster has a MY2007 car, the first year it was required.
There were still some holdout manufacturers who were using indirect TPMS systems.

As for your car’s light coming on . . . cold tires have lower pressure, perhaps low enough to warrant the light.
I have seen many guys inflate tires on a warm afternoon, only to have the light come on in the morning when the tire pressure was a few psi lower.

db4690 Of course you are right, but that was what I was trying to relay.

CDEas,

I have a 2006 Highland and have the same problem. The solution I found is to reset the sensor twice. The first time you do it the yellow light will go out. Press and hold again until the yellow sensor light blinks a few time. This has always worked for me. Good luck.

There are basically two types of tire pressure warning systems.

One uses pressure sensors/transmitters in each wheel. These do contain batteries and need periodic replacement. I’ve attached a document on these to give you some info.
http://tijil.org/Scion_Docs/Scion_06_misc_docs/2007sciontc_ncf%20Folder/tirepres.pdf

The second compares the signals from the wheel speed sensors. This type needs to be “reinitialized” every time you get new tires. I too have this type in my 2005 Scion, and i too have to go through the process. These are sensitive enough to trip when changing tires, even if you get the same size.
http://tijil.org/Scion_Docs/05_tC_Shop_Manuals/Repair%20Info/Service%20Bulletins/pd007t04%20-%20INITIALIZATION%20OF%20TIRE%20PRESSURE%20WARNING%20SYSTEM.pdf

Your owner’s manual should give you information on what type you have.