RC Car Not Driving Properly and Electronic Speed Controller Calibration

Troubleshooting the drive and speed controller on an RC car. The initial problem was an unpredictable response to the throttle which can be due to mis-calibration of the ESC, in this case it was two issues: One, the ESC required calibration and two, the transmitter reverse control was not functioning, which became apparent while calibrating the ESC. Swapping out the transmitter / receiver pair allowed the ESC to be calibrated correctly.