Retrieving Codes
NOTE:
Not all trouble codes will activate MIL (CHECK ENGINE light).
When Mode II is accessed (engine not running), codes stored in ECM memory will be flashed by MIL (CHECK ENGINE light). Long flashes (.6 second) indicate first digit of code. Short flashes (.3 second) indicate second digit of code. For example: 3 long flashes followed by 5 short flashes of MIL indicate a Code 35.