It's by design. It allows you to verify the light is working before you start the motor. You should be looking for the warning lights to illuminate when the key is in the on position (but the engine is not running) and to turn off as soon as, or shortly after, the engine starts on both your bike and your car.
The manual on the car tells you this, and I'm assuming the EX500's manual does as well (I don't have one).
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