How to Reset the Computer on a 2003 Ford Expedition
- 1). Place the Expedition's transmission in the "P" position. Shut down the engine and apply the parking brake.
- 2). Plug the scan tool's data cable into the Expedition's diagnostic data port, located underneath the dashboard on the driver's side. Power on the scan tool.
- 3). Choose "PCM" from the scan tool's main menu. Select "codes" and then choose "clear all codes."
- 4). Unplug the scan tool from the vehicle and power down the tool. Start the engine and check to make sure that the SES light is not illuminated. The computer is now reset.
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