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Q: ECU disconnected

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I lost my original car key i tried to get another one programed and it said ECU disconnected
My car has an automatic transmission.

Hi and thanks for contacting YourMechanic. First, remove the ground cable from the battery and let it stay off for 12 minutes. Then hook up the battery cable and retry the key. If your vehicle still gives you the same message, then the programming in the key does not match the ECU to the vehicle. Try putting the key in the drive door and lock and unlock the door 3 times. Then retry the key. This usually makes the car ECU recognize the key for starting. If you need further assistance with your vehicle, then seek out a professional to help you with your replacement key.

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