Clearing Diagnostic Trouble Codes

CAUTION: To avoid ECM damage, be sure ignition is "OFF" when disconnecting or reconnecting power to ECM (battery cable, ALDL jumper, ECM fuse, jumper cables, etc.).

Trouble code memory receives a continuous 12 volts even with ignition "OFF." After displaying and recording any trouble codes or after making repairs, ECM memory should be cleared by interrupting power for at least 30 seconds. This is accomplished by temporarily disconnecting battery. After clearing codes, it may be necessary to reset electronic accessories such as digital clock or radio.

When using a "Scan" tool, codes are cleared in same manner.