Retrieving Codes
NOTE:
Codes can also be retrieved using a scan tester. Trouble codes may also referred to as DTCs.
- Code retrieval starts with diagnostic circuit check. See DIAGNOSTIC CIRCUIT CHECK chart under CODE CHARTS. MIL will come on when ignition is on and engine is not running. When engine is started, MIL should go off. If light remains on while engine is running, a trouble code is present.
- If light does not come on with ignition on and engine off, inspect MIL circuit before continuing. If MIL fails to operate, see DIAGNOSTIC CIRCUIT CHECK chart.
- To retrieve codes, install jumper wire between ALDL diagnostic leads. See Fig 1 . Turn ignition on. Count number of flashes from MIL to identify code. See Fig 2 . For example, Code 12 will be flashed as follows: flash, pause, flash, flash.
- If system is operating properly, Code 12 should be displayed with ignition on and engine off, indicating diagnostic system is capable of storing codes. Code 12 will flash 3 times, followed by any stored trouble codes. Each code will be flashed 3 times starting with lowest code. Once all codes are displayed, cycle will repeat. After codes are retrieved, remove jumper wire from diagnostic leads to exit diagnostic mode.