The "Check Engine" light is turned on by the engine computer when it detects a problem that will adversely affect tail pipe emissions. There will also be a diagnostic fault code memorized in the computer. There are some codes that will not cause the light to turn, but can still be used by the mechanic when servicing the vehicle.
The severity of the code or problem can be determined by how the light acts. The least severe is when the light never turns on. Minor emissions-related problems will turn the light on, but it will go back off while you're driving when the problem corrects itself. More severe problems will turn the light on and it will stay on even when the problem goes away. The light will reset after turning the ignition off and restarting the engine. Still more serious, and the light will "latch" on and be on every time you run the engine, even if the problem goes away. Of course the problems aren't always intermittent, but when they are, those fault codes provide really valuable information for your mechanic.
If the light starts flashing while you're driving, . . . BAIL OUT and head for cover. Well, at least pull over and stop the engine. The light will flash when excessive unburned fuel is entering the catalytic converter. That can lead to it overheating causing permanent damage.
As for the controls on the steering wheel, it's likely the clock spring under the steering wheel is starting to break. Eventually the cruise control will not turn on and the air bag light will come on. When the air bag light is on, the system is disabled and the bags won't pop in a crash.
caradiodoc
Dec 16, 2009 at 5:37 AM
