Systems and methods are disclosed for securely injecting one or more key values into an electronic device by reading with a fingerprint sensor a manufactured key device having a key value. A secure communication channel between a fingerprint sensor and a secure processing system enables the reading, processing, and storing of the fingerprint sensor data from the key device. The key device includes a conductive substantially planar substrate (“substrate”) with raised conductive portions configured to encode a key value. The substrate can be made from a non-conductive material and have conductive material applied to the substrate to encode the key value. The substrate can be covered with an opaque, conductive layer so that the encoding cannot be visually perceived. The encoding scheme can be a QR code, a bar code, an image, an alphanumeric string, or other encoding. One or more electronic device access policies can be associated with a key value to control how an electronic device can be used when the electronic device is accessed with the manufactured key device.