Page 251 - Foton Workshop Manual - Tunland (AT)
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DIAGNOSTICS - ENGINE CONTROL SYSTEM                          04-105

                        failure phenomena before the test is conducted and the tester is connected in advance.
                        Then phenomenon simulation test may be conducted so as to determine whether or
                        not the tested circuits are normal.

                        In case of failures that are hard to be handled, the list of troubleshooting and diagnosis
                        codes may be utilized to conduct failure analysis/diagnosis so as to reduce the range
                        of failure and find out the failure location quickly. The said method is considered as       04
                        fairly practical and effective.
                 5 .    Diagnostic apparatus data-stream freezing method.
                        Use the data stream capturing function of diagnostic apparatus. Simulate the failure
                        conditions as per the frozen failure data recorded by the diagnostic apparatus when
                        people read the data stream displayed by the diagnostic apparatus.

                 6 .    Oscilloscope method.
                        Oscilloscope may be used to capture the waveforms such that the intermittent failures
                        may be found out quickly.
                 7 .    Other methods.

                        Part replacement method.To replace ECM or other control modules, conduct adequate
                        diagnosis of other external causes since ECM is an expensive product with high
                        reliability.

                     WARNING
                 To conduct part-replacement check of a control unit that might be damaged, the said
                 control unit shall be mounted onto a failure-free vehicle and subjected to tests.The
                 new control unit must not be mounted onto a faulty vehicle and subjected to relevant
                 tests so as not to damage the control unit.












































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