Daewoo Nubira Owner's Manual

Also see for NUBIRA: User manual Manual

Contents

Daewoo Nubira Owner's Manual Manual pdf 235 page image

ENGINE CONTROLS 1F – 413DAEWOO V–121 BL4 It informs the driver that a fault that affects vehicleemission levels has occurred and that the vehicleshould be taken for service as soon as possible. As a system check, the MIL will come on with thekey ON and the engine not running. When the en-gine is started, the MIL will turn OFF. When the MIL remains ON while the engine is run-ning, or when a malfunction is suspected due to adriveability or emissions problem, an OBD II Sys-tem Check must be performed. The procedures forthese checks are given in OBD II System Check.These checks will expose faults which may not bedetected if other diagnostics are performed first.Data Link Connector (DLC)The provision for communicating with the control moduleis the Data Link Connector (DLC). The DLC is used to con-nect to a scan tool. Some common uses of the scan toolare listed below: Identifying stored DTCs. Clearing DTCs. Performing output control tests. Reading serial data.DTC TYPESEach Diagnostic Trouble Code (DTC) is directly related toa diagnostic test. The Diagnostic Management Systemsets DTC based on the failure of the tests during a trip ortrips. Certain tests must fail two consecutive trips beforethe DTC is set. The following are the three types of DTCsand the characteristics of those codes:Type A Emissions related. Requests illumination of the Malfunction IndicatorLamp (MIL) of the first trip with a fail. Stores a History DTC on the first trip with a fail. Stores a Freeze Frame (if empty). Stores a Fail Record. Updates the Fail Record each time the diagnostictest fails.Type B Emissions related. ”Armed” after one trip with a fail. ”Disarmed” after one trip with a pass. Requests illumination of the MIL on the secondconsecutive trip with a fail. Stores a History DTC on the second consecutivetrip with a fail (The DTC will be armed after the firstfail). Stores a Freeze Frame on the second consecutivetrip with a fail (if empty). Store Fail Record when the first test fails (not de-pendent on consecutive trip fails). Updates the Fail Record each time the diagnostictest fails.Type D(Type D non–emissions related are not utilized on certainvehicle applications). Non–Emissions related. Does not request illumination of any lamp. Stores a History DTC on the first trip with a fail. Does not store a Freeze Frame. Stores Fail Record when test fails. Updates the Fail Record each time the diagnostictest fails.Important : Only four Fail Records can be stored. EachFail Record is for a different DTC. It is possible that therewill not be Fail Records for every DTC if multiple DTCs areset.Special Cases of Type B Diagnostic TestsUnique to the misfire diagnostic, the Diagnostic Executivehas the capability of alerting the vehicle operator to poten-tially damaging levels of misfire. If a misfire condition ex-ists that could potentially damage the catalytic converteras a result of high misfire levels, the Diagnostic Executivewill command the MIL to flash at a rate of once per secondduring those the time that the catalyst damaging misfirecondition is present.Fuel trim and misfire are special cases of Type B diagnos-tics. Each time a fuel trim or misfire malfunction is de-tected, engine load, engine speed, and engine coolanttemperature (ECT) are recorded.When the ignition is turned off, the last reported set of con-ditions remain stored. During subsequent ignition cycles,the stored conditions are used as a reference for similarconditions. If a malfunction occurs during two consecutivetrips, the Diagnostic Executive treats the failure as a nor-mal Type B diagnostic, and does not use the stored condi-tions. However, if a malfunction occurs on two non–con-secutive trips, the stored conditions are compared with thecurrent conditions. The MIL will then illuminate under thefollowing conditions: When the engine load conditions are within 10% ofthe previous test that failed. Engine speed is within 375 rpm of the previous testthat failed. ECT is in the same range as the previous test thatfailed.READING DIAGNOSTIC TROUBLECODESThe procedure for reading diagnostic trouble code(s) is touse a diagnostic scan tool. When reading DiagnosticTrouble Codes (DTCs), follow the instructions supplied bytool manufacturer.Clearing Diagnostic Trouble CodesImportant : Do not clear DTCs unless directed to do soby the service information provided for each diagnosticprocedure. When DTCs are cleared, the Freeze Frame