Two drivers turn to AAA auto experts to figure out why their dashboard lights go on for no apparent reason.
Q: I've taken my 1998 Ford Windstar minivan to a shop three times for the same problem: Sometimes when I stop hard, the traction control light on the dashboard flashes on and off and will not go off permanently until the car stops. This is very annoying, and after several trips to the shop, my mechanic can't find anything wrong. What can you suggest?
A: Of all the ways cars find to worry their drivers, flashing the warning lights seems to top the list. Like Lassie tugging at Timmy's sleeve, these lights manage to convey the idea that something's amiss without being able to articulate just what's wrong. It can be frustrating. In this case, you may not really have a problem. The traction control light comes on when sensors conclude that the tires are about to lose their grip or already have. A hard stop could activate the system, even without a skid. The light goes off when traction returns, as it does when the car finally comes to a stop.
Q: A few hours after I got my 1996 Ford F250 pickup truck back from the shop after a tune-up, the "check engine" light came on and has stayed on. The mechanics at the garage tell me that the motor has good compression, and the fuel mileage has improved somewhat. But the light is still on. Is there anything about a tune-up that would cause the light to come on like that?
A: Many things can cause a "check engine" light to glow. When a car's computer detects something about engine operation it doesn't like, it expresses itself, none too precisely, through this light. There's nothing inherent in a tune-up to make the light come on. Your mechanic should extract the codes from the truck's computer to see which system is implicated. It's also worthwhile to check the sensor connections. Since your truck is running more efficiently and has no other drivability problems, it's possible there is either a loose sensor connection (these things can happen during tune-ups) or a faulty sensor.
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This article was first published in May 2004. Some facts may have aged gracelessly. Please call ahead to verify information.