Q: Using proximity key, car starts without holding down brake

asked by on August 17, 2016

My car has a proximity start key. I’ve read the manual and it gives specific instructions that the key has to be in the car, the ignition switch has to be turned and the brake has to be depressed for the car to start. It also says that if the car’s operation deviates from these instructions that it should be immediately serviced. My car will only accomplish the first two parts of these rules: I have the key present in the car and I turn the ignition switch. What is dangerous is that my car starts without pressing and holding down the brake pedal. These instructions are in the yellow warning box and it also states that to ignore the warning could result in serious injury. Why does my car start without holding down the brake pedal?

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One possible cause for the problem may have to do with the switch that tells the vehicle that the brake pedal is depressed. The switch may have failed in a way that continuously tells the system that the brake pedal is depressed. It may not be the same circuit that will illuminate the brake lights all of the time. If the computer thinks the brake pedal is depressed, it will allow the vehicle to start. I agree this is a dangerous situation and I would avoid driving the vehicle until the brake system is diagnosed and repaired.

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