Memorized vs. Non-Memorized Codes
Some sensor or circuit failures are stored in ECU and are referred to as memorized codes. While other circuit failures, called non-memorized codes, are not stored. Non-memorized codes can be retrieved if ignition is not turned off before accessing codes.
NOTE:
To access non-memorized trouble codes, DO NOT stop engine. Connect jumper wire across data link connector terminals TEN and GND. Observe MIL, and note trouble codes.