Hi,

My friend has a 2004 4Runner with the tire pressure monitoring system. The warning light is lit on the dash, and a couple weeks ago he had an unexplained leak in the left front tire.

We took it to a tire shop, removed it from the vehicle and after several methods of inspection, could not find anything wrong with the tire. They even removed it from the rim and stretched it a bit.........still could find no holes. Therefore, I figure the only thing that could be wrong would be the valve stem, which contains these sensors.

Does anyone know how this system works? If he puts a new sensor/stem in the left front wheel............does it need to be programmed somehow? Or can any sensor be put on any one of the wheels and the vehicle will detect it? I just have no idea exactly how the system works.

I appreciate any insight you could provide.

 

isnt this covered by the toyota warranty? i dont think they would put sensors that are front/back/left/right wheel specific into each side, unless ofcourse if they are different sizes.

 

The monitor system checks all the tires and even the spare. Make sure the PSI is set to Manufacturer Settings and even check the spare tire.. Only think I can think of if the shop messes up the sensor when fixing the tire. And from what I gather, only a certain machine is suppose to be used to the 4Runner and such.

Check the spare and see if that is it, if not, might want to head to the dealer and see what they think.

 

The tire system monitors all 5 of the tires including the spare, make sure all of the tires are at recommended levels. Drive it around for a while if any of the tires are low (~less than 32 psi), I think it took about 50 miles for my low tire sensor light to turn off.

If the sensor is "broke", even a hairline crack in the plastic case, or just defective, you have to have a new sensor installed. But first you must have all of the serial #'s from all 5 sensors (yes that means you have to have all of the tires removed, increasing the chance that you break another sensor) to re-program the system at the dealership. It is a 7 digit series of letters/#s on the right side of the sensor, that I believe is just below a longer series of letters/#s. You can get a detailed picture showing exactly where they are from the dealership if necessary.

Just make sure you write all of the sensor #s down for future reference.

P.S. If you can't tell, I have been through this very nightmare, the system is a POS and I called Toyota and filed a complaint. No way to just disable the system according to the dealership its part of the VSC ecu. If you do a search you will find more info about this.