LAUNCH
Creader 7001S/8001S English User’s Manual
2
system turns on a warning lamp (MIL) on the vehicle instrument panel to alert the
driver typically by the phrase of “Check Engine” or “Service Engine Soon”. The
system will also store important information about the detected malfunction so
that a technician can accurately find and fix the problem. Here below follow three
pieces of such valuable information:
1) Whether the Malfunction Indicator Light (MIL) is 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 second character, a
number, 0-3; other three characters, a hex character, 0-9 or A-F 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: