For 1990-2009 cars

Clearing History Codes: After diagnosing a system problem, clear all history DTCs in order to prevent any future misdiagnosis.

Disconnecting the battery or module connectors will not clear a history DTC. A DTC may only be cleared by using one of the following methods:

• | Use a scan tool.

• | A module will clear a history DTC after 50 drive cycles.

Most of the diagnostic tables refer to the scan tool for diagnostic support.