I went up over 4,000' in sub-freezing weather and noticed my 2007 Tacoma tire pressure light came on. Checked the 4 tires on the ground - saw no problem and continued on my way. A couple of days later, back at sea level and ~60deg the light has stayed on. Aired up all 5 tires - yes, spare too - and the light remains on. Manual calls for 29psi, I inflated to 30psi. Light is still on.
Do the batteries in the tpms fail? Would a dealer charge for an opinion? When I am near a faster connection I'll Utube search for a reset procedure, but was wondering if the one copied below from a Toyota forum was valid.
On a Chevy it was something like the following:
1) turn the key on but don't start 2) turn the lights on and off 3 times, after the third time the vehicle horn will beep once 3) let the air out (or add air) of the front left tire until the vehicle horn sounds 4) go to the next tire clockwise (front right, rear right, rear left) and adjust air pressure until the horn honks for each one 5) turn the key off and the system goodI had a similar problem ~3-4 years ago and forget what I did then.