Operation CHARM: Car repair manuals for everyone.

Clearing Diagnostic Trouble Codes

Mode Change Operation:






1. Turn the ignition key on.
2. Turn the diagnostic mode selector on the Engine Control Module (ECM) fully clockwise and wait more than two seconds then turn the selector fully counterclockwise. The ECCS system is now in mode 2.
3. Turn the diagnostic mode selector on the ECM fully clockwise and wait more than two seconds then turn the selector fully counterclockwise. The ECCS system is now in mode 1.
ECM memory is now erased.


^ Switching the modes is not possible when the engine is running.

^ When the ignition switch is turned off during diagnosis in each mode, and then turned back on again after power to the ECM has dropped off completely, the diagnosis will automatically return to Diagnostic Test Mode I.

^ Turn back diagnostic test mode selector to the fully counterclockwise position whenever vehicle is in use.