When the check engine light illuminates on the dash in a Nissan
Sentra, it is an indication that the computer has recognized a problem within its sphere of influence. Once the problem has been addressed and corrective action completed, the computer can be reset by erasing the existing codes.
Insert the code scanner's connector into the OBD port located under the dash to the right of the steering column.
Turn the ignition key to the run position. Make sure the engine is off.
Press the button for "Read" on the code scanner. Within less than 1 minute, the scanner will display all failure codes that are stored in its memory.
Write down the failure codes displayed by the scanner. Cross-reference the codes with the code sheet that comes with the scanner. The codes are displayed with a letter followed by a four-digit number code. Deciphering these codes by cross-referencing them with the code sheet offers an explanation of the failure.
Turn the key off. Correct the failure so that the computer can be reset.
Turn the ignition key on, keeping the engine off. Press the "Erase" button on the scanner. Start the vehicle and allow it to run for 5 minutes. Watch for the check engine light to come back on. If it does, the problem has not been corrected. If it stays off, the problem has been successfully resolved.
