TPMS Components


Compensating for Temperature Changes
For the 2005 Outback, Subaru specifies tire pressures set with cold tires (60° F). When tires are warmer or cooler than 60° F, pressure needs to be adjusted. Compensate for large swings to colder temperatures according to the following table.
If you drive out of your heated garage on a cold day and the TPMS warning light comes on, stop to check if the tires are low. Chances are you need air due to the swing to colder temperatures.
If you’ve been driving for a while (more than 20 minutes) and the light illuminates, you probably have a problem caused by a tire going flat.


  front rear
Garage temperature Recommended pressure (psi)
60° F 32 30
Outside temperature Adjusted pressure (psi)
30° F 35 30
10° F 37 35
-10° F 39 37


See more information in the Maintenance and Service portion of the Owner’s Manual.


Major Subaru TPMS components include:

  • Integrated valve stem and air-pressure sensor/ transmitter assembly with battery – each wheel
  • Receiver – under the driver’s seat
  • TPMS warning light – part of the instrument panel



How TPMS Works


The wheels’ air-pressure sensor/transmitter assemblies transmit individual air-pressure levels via radio signal to the receiver/control unit. Roll switches in the assemblies turn on the sensors when vehicle speed reaches between seven and 20 mph.


Transmitter data include detected air pressure, ID code and a code indicating the transmitter’s current mode. Each assembly’s sensor takes measurements every 30 seconds, which are transmitted every 60 seconds. After the vehicle has stopped for 15 minutes, the sensors enter sleep mode to conserve their batteries. They have life expectancies of 10 years or 100,000 miles.


The receiver/control unit collects data from the sensor/transmitter assemblies via a built-in antenna. If air pressure drops between 26 and 27 psi in one or more of the tires, the unit illuminates the warning light in the instrument panel (the system design does not indicate which tire is low).


TPMS – Important Safety Technology


Subaru equips vehicles with TPMS to improve safety. By warning of a tire’s air-pressure loss, TPMS helps drivers avoid accidents. An added benefit is the reduced wear and tear to a vehicle’s power train and chassis, potentially improving durability and lowering the cost of ownership.


(Don’t forget to check the air pressure in your tires at least once a month – especially after drastic fluctuations in ambient temperature. An investment in a quality tire gauge can save you money and improve safety!)




Add to Favorites
Added to Favorites  Close
Rate this Article

(4.3 based on 12 ratings)