This may be old news to some of you, but useful to others.
I’ve been battling the “Low Tire Pressure” light on the dashboard of my wife’s Toyota. Even if I keep all four tires at exactly the same pressure, the stupid light wants to come on. I had to get some new tires for my pickup, and asked the guy at the local tire shop if he had any ideas. He suggested two things:
-First, check the air pressure in the spare tire. He said Toyota is famous for putting a tire pressure sensor (TPS) in their spare tires. If the spare has low pressure it will trip the warning light just like any of the four tires on the road.
-Second, check tire tire decal on the door post of the driver’s door. He said even if all four (five) tires are at exactly 34 psi, the warning light will come on if the recommended pressure is 40 psi.
I haven’t had time to check and see if his tips are relevant to my wife’s car, but you can bet I’m going to at least try them before I schedule a trip to the Toyota dealer. It’s a little embarrassing as a “professional mechanic” to be so stupid about something as simple as TPS systems, but… I console myself with the knowledge that most tire shop guys and Toyota mechanics wouldn’t know how to adjust the concave clearance on a combine.
