User manual

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On-Board Diagnostics (OBD) Diagnostic Service Definitions
Figure 4-3 Example: DTC “P0237”
In this example, definitions listed for Position 3 are only valid for DTCs starting with “P”. For other
codes (C, B, U) there are other definitions. Please refer to ruling OBD standards for more
information.
Code Ranking
OBD-II/EOBD 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 code erase procedure.
Vehicle manufacturers have implemented the ranking differently.
4.6.4 Service $04: Clear/Reset Emission-related Diagnostic Data
NOTE:
i It is recommended to perform the Clear Code/Reset function with the engine off and the ignition
switched on.
The purpose of this service is to clear codes and turn off the MIL. It is recommended to print the
DTCs before erasing them, for comparison after repairs are made.
Clearing the code memory erases all diagnostic information stated in “Reset Information” below:
Position 1
Position 2
Position 3
Position 4 & 5
P0237
Table 4-4 Reset Information (sheet 1 of 2)
Service Items to reset
$01
Status of system monitoring tests
Number of diagnostic trouble codes
Distance travelled while MIL is activated
Number of warm-ups since DTCs cleared
Distance travelled since DTCs cleared
Time run by the engine while MIL is activated
Time since diagnostic trouble codes cleared
$02
Diagnostic trouble code for freeze frame data
Freeze frame data