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In the process of diagnosis, if the device shows “System is OK” or “No Trouble Code”, it means there is no related trouble
code stored in ECU or some troubles are not under the control of ECU. Most troubles are mechanical system troubles or
executive circuit troubles. It is also possible that the signal of a sensor may be inaccurate but within limits, which can be
examined using Live Data.
CLEAR TROUBLE CODE
It allows for clearing current and historical trouble codes stored in the ECU memory, under the premise that all the troubles
have been resolved.
Some troubles are immediately detected by the ECU with the key in the run position and without the engine running.
Other troubles are not detected until very specific test conditions are met such as engine coolant temperature within a
range, speed within a range for a duration of time, throttle percentage within a range, etc.
If the trouble codes are erased when the trouble remains unresolved, the trouble code will reappear in the ECU the next
time the ECU performs the specific diagnostic test for that trouble.
If the trouble is resolved but there is a stored trouble code, sometimes the ECU will detect the resolution and clear the
trouble code or more likely, classify it as “historical” trouble.
If the trouble is resolved and the user clears the trouble codes, the trouble history will be cleared.
If the user intends to have another colleague or mechanic investigate the problem, it is not recommended for the user to
clear the trouble code since doing so may erase information helpful to others who may investigate the issue.
DTC Status
Descriptions
Suggestions
Summary of Contents for IP819TP
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