Historical Diagnostic Trouble Codes (DTCs)
WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2018 Lincoln Navigator, 2018 Lincoln MKZ, 2018 Lincoln MKX, 2018 Lincoln MKT, and 2018 Lincoln MKC. However, it is still accessible from the selected car via links, so may be relevant.
Historical DTCs use bit 5 (the DTC test failed at least once since last code clear) to indicate that a DTC is no longer confirmed or pending, but has failed at least once since the last time the DTCs were cleared. The bit 5 is designed to eventually age out and clear in 80 drive cycles (255 in the future). The scan tool does not allow a technician to retrieve historical DTCs unless there are no active DTCs present. This information, in conjunction with manufacturer freeze frame and snapshot data, may be useful in diagnosing a noticeable fault that did not progress to MIL status, or an extended amount of time has occurred before diagnosis, and the confirmed DTC has cleared.