Abstract: A transfer case motor controls the rotation of a cam. The cam actuates various gear states of a transfer case of a four-wheel-drive vehicle. A contact plate rotates with the cam and encodes the position of the cam as a four-bit binary code. The code is such that when the cam travels between any two gear states, one bit of the four-bit code stays constant from the initial gear state until the final gear state is reached. The single bit can thus be observed to determine that the final gear state has been reached. The encoding scheme is also such that the bit which stays constant always assumes the same state.

Abstract: An interior lamp control using a microprocessor to monitor the ignition switch, door ajar switches, and vehicle speed deactivates the interior lamp if vehicle speed exceeds a speed threshold even though the state of the input switches otherwise indicates that the interior lamp should be illuminated. The lamp will not again illuminate until after the speed decreases below a lower speed threshold.