Nissan Repair Questions? Ask a Mechanic for Answers ASAP
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The mechanical key is how you would get into the car if the battery is dead. The buzzing noise is most likely from the ABS actuator. I would charge up the battery and reconnect it and see if the buzzing stops. It could be simply acting up due to low battery voltage. If it still buzzes after the battery is charged, it will need to be replaced.
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