Selecting Clear Codes
WARNING: This page is about a different car, the 1995 Cadillac Seville. However, it is still accessible from the selected car via links, so may be relevant.
Selecting "CLEAR CODES?" test will result in "CODES CLEAR" message being displayed with selected system name for 3 seconds, indicating all stored trouble codes have been erased from memory. After 3 seconds, display will automatically return to next available test type level (i.e., PCM SNAPSHOT?).
After a code has been cleared, make a complete ignition cycle and possibly a test drive. Ensure code does not reset.