ScanTool Launch CReader - Manual (Page 10)

LAUNCH CreaderV User’s Manual
commanded 'on' or 'off';
2) Which, if any, Diagnostic Trouble Codes (DTCs) are stored;
3) Readiness Monitor status.
2.2 Diagnostic Trouble Codes (DTCs)
OBD II Diagnostic Trouble Codes are codes that are stored by the
on-board computer diagnostic system in response to a problem found in
the vehicle. These codes identify a particular problem area and are
intended to provide you with a guide as to where a fault might be
occurring within a vehicle. OBD II Diagnostic Trouble Codes consist of a
five-digit alphanumeric code. The first character, a letter, identifies which
control system sets the code. The other four characters, all numbers,
provide additional information on where the DTC originated and the
operating conditions that caused it to set. Here below is an example to
illustrate the structure of the digits:
4