March 21, 2010

Car Talk

What to do when the car battery's dead and jump-starting it sets off the alarm

Syndicated columnists

Dear Tom and Ray:

I am trying to jump-start my husband's 2008 Honda Accord. It's been sitting for a few months since he was deployed to Iraq, and I need to move the car ASAP before the street sweepers come. However, when I connect the last jumper-cable clamp, the horn starts blowing. How do I make it stop so I can jump the car and not have the whole neighborhood staring at me? Thanks!

Ray: Jump-start it in the middle of the night, Lisa. No one's out staring at that hour.

Tom: Actually, it's your alarm system that's going off. When the battery died, the car's factory-installed alarm system assumed that someone was tampering with the battery or had disconnected it in order to break into the car.

Ray: So when you hook up the jumper cables, it's like you're replacing the battery. Since the alarm's memory is intact, it picks up right where it left off, and starts honking the horn and flashing the lights. It also immobilizes the engine so you can't start the car.

Tom: So here's what you need to do. Sometime in the middle of the day (don't listen to my brother), hook up the jumper cables. The horn will start to blow. As soon as it does, using the key fob, lock and then unlock the doors. You also can do this with the original Honda key in the driver's door.

Ray: Once the car is locked and then unlocked with a legitimate key or key fob, the alarm will reset and you'll be good to go.

Tom: And from then on, just try to start it (or better yet, drive it) every few weeks to prevent the battery from dying.

(Car Talk is a nationally syndicated column by automotive experts (and brothers) Tom and Ray Magliozzi. Write to them at the Car Talk Web site.)


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