Today: Outsmarted by Your Car?

Dear Car Talk

Dear Car Talk | Dec 04, 2014

Dear Car Talk:

While on a recent business trip with a bunch of fellow engineers, the battery in my 2010 Toyota Highlander with a keyless-start system went dead. Of course, we blamed it on the youngest member of the team, whom we had forced to do the long drive that day. But the reality is that the battery was four years old, and it just died. Luckily, we found a helpful engineer from Boeing who happened to be parked near us -- an electrical-power expert, too!

He jumped the car for us for about five minutes and got the basic lights and beeps working again, but the car would not start. The green "ready" button was lit up for the push-button starter, but no response. So after checking all the stuff we could think of, we got the owner's manual out and handed it to the rocket scientist on the team. In time, the rocket scientist found the problem. In order to start the car after jumping it, one has to open and close the driver's door with the ignition off! Bingo -- it worked. Why have such a nuisance safety procedure? Most folks would have headed for the tow truck or dealer before figuring it out. Please comment!

-- Steven

Outsmarted by a car. Welcome to my world, Steven. The reason you needed to open and close the door is because of the way the smart key communicates with the keyless ignition system. With a push-button start system, the car and the smart key have to talk to each other. Before starting the car, the computer asks, "Are you there, key?" And the key responds: "Yo, dude, it's me. We're good."

But the computer doesn't know to look for the key unless the driver's door is opened and closed. That's its signal to check for the presence of the correct smart key. Otherwise, it doesn't even ask. And since the battery died when the door was closed, and then you opened the door while the battery was still dead, the computer never got the (open door/closed door) signal to check for the presence of the key. But congratulations on saving yourself time and money by reading the owner's manual and solving the problem.

Resorting to the owner's manual is atypical male behavior, Steven. It's a humiliation greater than even asking for directions! I'm both proud and ashamed of you.


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