Breakdown phenomenon
An A4L of 2016 Ao Di, equipment CUJ engine, travel course of development is 59 600km. Lamp of the breakdown after engine is started illumes, along with late motive flameout. Start afresh, after engine runs shorter time normally, appear to shake apparently and again flameout.
Breakdown is diagnosed with eliminate
Receive the test-drive after the car, breakdown is belonged to solid. The engine that start, arrive when water temperature rise when 99 ℃ , car begins to appear to shake apparently, subsequently flameout. During, water is warm those who rise is very fast, achieved 1s to rise almost the speed of 1 ℃ .
Join diagnostic computer ODIS inquires malfunction code above all, "01 engine are electronic-controlled system " in memory has undermentioned breakdown code:
Voltage of 1. sensor reference " A " too low, static state;
Potentiometer of door of 2. solar term is suspect signal, static state;
3.Because accept wrong and numeric function to suffer,be restricted, static state;
4.Engine refrigeration unit is not enough, static state.
Combine breakdown phenomenon and malfunction code analysis, bring about engine to shake the most possible reason is breakdown of solar term door. Tear open door of check solar term and plug circuitry, did not discover unusual, unplug also did not discover after next outlet unusual, suspicion is breakdown of solar term door. Exchange then solar term door, but breakdown did not produce a change, showing solar term door is normal, breakdown may pass to be concerned lowly with referenced voltage.
Inquire the data is informed, a certain terminal of engine computer offers voltage to a few specific sensor, this voltage is called to consult voltage. Referenced voltage is the imitate voltage with engine computer good programming, it is 5V commonly. Referenced voltage cent is two kinds: Referenced voltage A and referenced voltage B. The sensor voltage A of this car allocates the terminal such as A35(T105/35) , A54(T105/54) , B32(T91/32) and B33(T91/33) . If pursue,circuit pursues related inquiry 1 with the graph 2 are shown.
Graph 1 engine controls unit circuit to pursue 1
Graph 2 engine control unit circuit to pursue 2
By the graph 1, the graph shows engine 2 times to control unit circuit graph to be informed, among them A35(T105/35) terminal offers referenced voltage for the following sensor: G71 of pressure sensor of G42 of sensor of G28 of sensor of engine rotate speed, inlet temperature, air inlet duct and engine thermoregulation carry out component N493. A54(T105/54) terminal controls the T6/2 terminal of unit J338 to offer referenced voltage for solar term door, t6/2 terminal is potentiometer sensor namely 1 with the power supply terminal of 2. A35 and A54 are the referenced voltage A with computer good programming. Accordingly, suspicion is interior of the certain in above component appeared short circuit phenomenon, cause referenced voltage to reduce, the power supply tension that causes solar term door thereby is insufficient, and cannot work normally.
The power supply voltage that measures T6/2 of outlet of solar term door is 1.8V, should be 5V left and right sides normally, explain power supply voltage is too low, ordinal the sensor outlet that in unplugging next circuit pursue, involves, measure solar term door to handle power supply tension again, when unplugging next engine thermoregulation carry out component N493, the voltage of T6/2 of terminal of solar term door turned into 5.01V, referenced voltage returns to normal! Start engine right now, move smooth, because this specification is N493 of thermoregulation executive component,appeared problem. Decompose 3) of graph of executive component N493(, discover its interior infiltration cooling fluid, component already was corroded.
Graph the thermoregulation of the 3 solution that be torn open carries out component N493
Disconnect N493 outlet is read take malfunction code, "01 engine control unit " the malfunction code of the record by two before, became the following two:
By-pass valve of 1. cooling fluid is started, open circuit, static state;
2.Cooling fluid is not worth indication sensor, electric breakdown, static state.
Because thermoregulation carries out component N493 and water pump to be one whole, be forced whole undertakes changing. Order a N493 and water pump assembly afresh, measure 1, 2 terminal resistor is 48 Ω , install car test-drive, everything is normal.
Maintain brief summary
This car because N493 in-house short circuit, pull low the power supply voltage of referenced voltage A, bring about numerous carry out implement cannot work normally with sensor, include sensor of engine rotate speed among them, because of breakdown of this engine occurrence flameout. The trouble that encounters circuit respect must stand in global height to consider an issue, if confine is in breakdown itself or hint according to malfunction code only, be introduced easily wrong road.
Additional, we also need to notice to study car new technology, for example model of Ao Di B9 cancelled thermostat, and N493 of use thermoregulation executive component replaces thermostat, if do not understand this technology, also can encounter an obstacle when removing trouble and take roundabout way.
To achieve energy-saving with environmental protection two old ends, contemporary engine management used technology of much square position control. Among them engine heat manages even if these control the main component in the technology. The innovation that masses Motor Corporation rolls out on new-style engine heat runs a system (ITM) , realized thermoregulation of completely alterable engine, undertake to cooling fluid temperature the target is controlled. Component of the core in this system is the breakdown component in the article, engine thermoregulation is carried out implement) of component of N493(rotary valve coming back, its structure is shown 4 times like the graph.
The cooling fluid that realizes different discharge through the rotational angle of two rotary valve coming back is in the condenser of supercharger of condenser of body of cylinder lid, cylinder, engine oil, turbine, transmission and advocate condenser (radiator) between flow, make engine work temperature holds the range in 86~107 ℃ in. This system has range of 3 main control (graph 5) :
1. warming-up limits: Warming-up operating mode is not had to other operating mode seam transfer.
2. temperature controls limits: Partial load and full load operating mode.
Limits of 3. continue operation pattern: Machine hind stops in engine, to prevent cooling fluid to pursue in eddy 4 engine thermoregulation is carried out implement knot composition of a picture pursues 5 engine thermoregulation is carried out implement rotate angle and engine operating mode boil in graph annulus supercharger and cylinder lid, engine controls unit to start continue to run a function through a collection of illustrative plates, run time can amount to 15min, right now engine thermoregulation is carried out implement the position that N493 rotary valve coming back is in ° of 160 ° ~255, jump over to cooling degree demand in continue operation pattern tall, the point of view that rotary valve coming back opens is older, when 255 ° , receive to advocate the circumfluence of water cooler is opened completely, delivered quantity of heat is the biggest.
Exceed 113 ℃ when engine temperature, urgent constant temperature implement can open lead to advocate the by-pass valve of condenser. If rotate,component of a powerful person malfunctions, EPC breakdown lamp illumes, limitation of engine rotate speed is under 4 000r/min. Engine thermoregulation is carried out implement there is Huo Er type to change horn to sensor on control plate, send position of rotary valve coming back engine to control unit, regard the position of rotary valve coming back as feedback information. This working voltage that changes horn to sensor is consulted by 5V voltage power source is supplied, its short-circuit breakdown, the regular job of the other electron cell that can affect power supply of power source of 5V referenced voltage, this is the real reason of this breakdown case, fortunately the author is carried out to engine thermoregulation implement working principle understands somewhat, make breakdown is able to eliminate in time. Carry this breakdown case, also make we achieve new-style heat to manage a system to understand somewhat to masses engine.
Graph 4 engine thermoregulation is carried out implement knot composition of a picture
Graph 5 engine thermoregulation is carried out implement rotate angle and graph of engine operating mode
