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Figure 3-4 Sample of read ECU information screen
Read Trouble Code
Read trouble codes (DTCs) that are stored in ECU. For the trouble code, the diagnostic
instrument will give specific detailed definitions and explanations to help you locate and
eliminate the car fault.
Stored Code
Stored codes are the current emission-related DTCs from the ECM of the vehicle.
OBDII Codes have a priority according to their emission severity, with higher priority
codes overwriting lower priority codes. The priority of the code determines the
illumination of the MIL and the codes erase procedure. Manufacturers rank codes
differently, so expect to see differences between makes.
Pending Code
These are codes whose setting conditions were met during the last drive cycle, but
need to be met two or more consecutive drive cycles before the DTC actually sets.