Isuzu NPR Fire truck 4HK1 engine repair manual

Seksyon 1A

Sistema ng kontrol ng makina

Talaan ng Nilalaman

Pahina

Sistema ng kontrol ng makina..1A-4

Mga Pag-iingat1A-4

Pag-andar at prinsipyo ng paggana. 1A-5

Diagram ng pagsasaayos ng mga bahagi.. 1A-21

Diagram ng sirkit.. 1A-25

Paano mag-diagnose ng kasalanan1A-42

Mga pamamaraan ng operasyon ng diagnosis ng kasalanan sa pamamagitan ng fault diagnostic meter1A-48

Pangkalahatang-ideya ng pagsusuri ng pag-andar.. 1A-50

Pagtatanong. 1A-51

Pagsusuri ng sistema ng kontrol ng makina. 1A-53

Listahan ng datos ng fault diagnostic meter1A-55

Mga nilalaman ng listahan ng datos ng fault diagnostic meter1A-58

Output ng fault diagnostic meter1A-64

Pagkabigo sa pagsisimula ng fault diagnostic meter. 1A-65

Pagkabigo sa komunikasyon ng fault diagnostic meter (sanggunian)1A-67

Pagkabigo sa komunikasyon sa ECM (sanggunian)1A-71

Pagkumpirma ng sistema ng pagsisimula. 1A-74

Pagkumpirma ng sistema ng sirkit ng kuryente ng pag-ilaw ng MIL ng makina. 1A-77

Pagkumpirma ng sistema ng sirkit ng kuryente ng pagkurap ng MIL ng makina. 1A-78

Inspeksyon ng sistema ng kontrol ng pag-resiklo ng gas ng tambutso (EGR). 1A-80

Inspeksyon ng sistema ng kontrol ng pagpainit. 1A-84

Inspeksyon ng sistema ng kontrol ng exhaust brake/paghihigpit ng air inlet. 1A-87

Pangkalahatang-ideya ng diagnostic trouble code (DTC).. 1A-92

DTC P0016 (Flash code 16)1A-95

DTC P0087 (Flash code 225)1A-97

DTC P0088 (Flash code 118)1A-103

DTC P0089 (Flash code 151)1A-109

DTC P0091, P0092 (Flash code 247)1A-112

DTC P0093 (Flash code 227)1A-116

DTC P0107, P0108 (Flash code 32)1A-122

DTC P0112, P0113 (Flash code 22)1A-127

DTC P0117, P0118 (Flash code 23)1A-132

DTC P0122, P0123 (Flash code 43)1A-137

DTC P0182, P0183 (Flash code 211)1A-142

DTC P0192, P0193 (Flash code 245)1A-147

DTC P0201, P0202, P0203, P0204 (Flash code 271,272,273,274)................................................... 1A-157

DTC P0217 (Flash code 542)...................................................................................................... 1A-170

DTC P0219 (Flash code 543)...................................................................................................... 1A-172

DTC P0234 (Flash code 42)........................................................................................................ 1A-175

DTC P0299 (Flash code 65)........................................................................................................ 1A-178

DTC P0335 (Flash code 15)........................................................................................................ 1A-182

DTC P0336 (Flash code 15)........................................................................................................ 1A-187

DTC P0340 (Flash code 14)........................................................................................................ 1A-190

DTC P0341 (Flash code 14)........................................................................................................ 1A-195

DTC P0380 (Flash code 66)........................................................................................................ 1A-198

DTC P0381 (Flash code 67)........................................................................................................ 1A-201

DTC P0404 (Flash code 45)........................................................................................................ 1A-205

DTC P0409 (Flash code 44)........................................................................................................ 1A-208

DTC P0477, P0478 (Flash code 46)............................................................................................. 1A-212

DTC P0500 (Flash code 25)........................................................................................................ 1A-216

DTC P0502, P0503 (Flash code 25)............................................................................................. 1A-218

DTC P0563 (Flash code 35)........................................................................................................ 1A-223

DTC P0601 (Flash code 53)........................................................................................................ 1A-225

DTC P0602 (Flash code 154)...................................................................................................... 1A-226

DTC P0604, P0606, P060B (Flash codes 153, 51, 36).................................................................... 1A-228

DTC P0641 (Flash code 55)........................................................................................................ 1A-230

DTC P0650 (Flash code 77)........................................................................................................ 1A-233

DTC P0651 (Flash code 56)........................................................................................................ 1A-237

DTC P0685, P0687 (Flash code 416)........................................................................................... 1A-241

DTC P0697 (Flash code 57)........................................................................................................ 1A-245

DTC P1093 (Flash code 227)...................................................................................................... 1A-248

DTC P1261, P1262 (Flash code 34)............................................................................................. 1A-253

DTC P1404 (Flash code 45)........................................................................................................ 1A-255

DTC P1621 (Flash code 54)........................................................................................................ 1A-257

DTC P2122, P2123 (Flash code 121)........................................................................................... 1A-258

DTC P2127, P2128 (Flash code 122)........................................................................................... 1A-264

DTC P2138 (Flash code 124)...................................................................................................... 1A-270

DTC P2146, P2149 (Flash code 158)........................................................................................... 1A-273

DTC P2228, P2229 (Flash code 71)............................................................................................. 1A-279

DTC P253A (Flash code 28)....................................................................................................... 1A-284

DTC P256A (Flash code 31)....................................................................................................... 1A-287

DTC U0073 (Flash code 84)....................................................................................................... 1A-291

Diagnosis ng sintomas................................................................................................................... 1A-296

Mga Pangyayari: Intermittence.......................................................................................................... 1A-297

Sintomas: Mahirap simulan........................................................................................................ 1A-300

Mga Pangyayari: Surge, hindi matatag na idling o pagtigil ng makina.................................................................... 1A-303

Mga Pangyayari: Mataas na idling speed.................................................................................................... 1A-306

Sintomas: Emergency stop......................................................................................................... 1A-307

Sintomas: Emergency change..................................................................................................... 1A-309

Sintomas: Kulang sa lakas, pagkabigo sa pagpapabilis o pagkaantala sa pagtugon........................................................... 1A-311

Mga Pangyayari: Intermitted operation, pagkabigo sa pagpapabilis................................................................... 1A-314

Sintomas: Ingay ng pagkasunog...................................................................................................... 1A-316

Sintomas: Mababang kahusayan sa pagtitipid ng gasolina.................................................................... 1A-317

Mga Pangyayari: itim na usok mula sa gas ng tambutso................................................................................... 1A-319

Sintomas: Puting usok mula sa gas ng tambutso.................................................................................. 1A-321

Mga pangunahing parameter ng sensor.............................................................................................................. 1A-323

Mga espesyal na kasangkapan............................................................................................................................. 1A-325

Programa............................................................................................................................... 1A-326

Panuntunan sa programming...................................................................................................................... 1A-326

Programa............................................................................................................................... 1A-326

Pag-aaral ng injection pump.............................................................................................................. 1A-328

Pagsasaayos............................................................................................................................... 1A-328

Sistema ng kontrol ng makina

Mga Pag-iingat

Paggamit ng mga kasangkapan sa pagsusuri ng sirkit

Sa kaso ng diagnosis ayon sa programang diagnostic, huwag gamitin ang test lamp para sa diagnosis ng power train electrical system maliban kung tinukoy. Kung gagamitin ang probe terminal para sa programang diagnostic, gamitin ang terminal testing adapter kit 5-8840-2835-0.

Available na mga bahagi ng kuryente sa merkado

Ang available na mga bahagi ng kuryente sa merkado ay nangangahulugan ng mga bahagi ng kuryente na binili mula sa merkado upang mai-install sa sasakyan. Dahil ang mga bahaging ito ay hindi isinasaalang-alang sa yugto ng disenyo ng sasakyan, bigyang pansin ang mga ito kapag ginagamit ang mga bahaging ito.

Pag-iingat:

Ang available na power at ground ng mga bahagi ng kuryente sa merkado ay dapat na ikonekta sa sirkit na hindi nauugnay sa sirkit ng electrical control system.

Bagaman magagamit ang mga available na bahagi ng kuryente sa merkado, maaaring maging sanhi ito ng functional fault ng electrical control system sa ilang mga kaso. Kasama rito ang mga device na hindi konektado sa electrical system, halimbawa, ang mobile phone, radyo. Samakatuwid, sa diagnosis ng power train, suriin muna kung ang mga ganoong available na bahagi ng kuryente sa merkado ay naka-install. Kung gayon, alisin ang mga ito sa sasakyan. Kung ang kasalanan ay umiiral pa rin pagkatapos ng pag-alis ng bahagi, sundin ang pangkalahatang daloy para sa diagnosis.

Pinsala dahil sa ESD

Dahil ang mga elektronikong bahagi sa electrical control system ay maaaring gumana sa ilalim ng napakababang boltahe, madali silang masira dahil sa ESD. Ang ilang mga elektronikong bahagi ay masisira ng static electricity na mas mababa sa 100V na hindi mapapansin ng tao. Ang mapapansin ng tao na ESD ay nangangailangan ng 4000V boltahe. Sa maraming mga kaso, ang tao ay magdadala ng static electricity, kung saan ang friction at induction electrification ang pinaka karaniwan.

● Kapag ang tao ay gumagalaw mula sa gilid hanggang sa gilid sa upuan, ito ay magbubunga ng frictional electrification.

● Kapag ang taong may suot na insulated shoes ay malapit sa mataas na electrified na bagay, ang electrostatic induction ay magaganap sa sandaling ang tao ay dumapo sa lupa. Ang tao ay magiging electrified kapag ang mga singil ng parehong polarity ay nakakatugon sa mga singil ng kabaligtaran na polarity. Dahil ang static electricity ay magdudulot ng pinsala, maingat na hawakan ang mga elektronikong bahagi at subukan ang mga ito.

Pag-iingat:

Sundin ang mga sumusunod na panuntunan upang maiwasan ang pinsala dahil sa ESD:

● Huwag hawakan ang mga contact pins ng ECM terminal at mga elektronikong bahagi na nakasolder sa ECM circuit back plate.

● Huwag buksan ang mga pakete maliban kung ang paghahanda ng pag-install ng bahagi ay natapos na.

● Ikonekta ang pakete at normal na ground ng sasakyan bago kunin ang mga bahagi sa pakete.

● Kung gumagalaw mula sa gilid hanggang sa gilid sa upuan, o nakaupo mula sa nakatayong pustura o pinapaandar ang bahagi habang gumagalaw sa isang tiyak na distansya, tiyaking hawakan ang normal na ground bago i-install ang bahagi.

Pag-andar at prinsipyo ng paggana

Sistema ng kontrol ng makina (common rail)

Pangkalahatang-ideya at detalye ng sistema

Ang sistema ng kontrol ng makina ay nangangahulugan ng electrical control system upang kontrolin ang makina sa pinakamainam na estado ng pagkasunog ayon sa kondisyon ng pagmamaneho. Binubuo ito ng mga sumusunod na bahagi:

● Elektronikong kinokontrol na fuel injection system (common rail type)

● EGR

Bukod pa rito, kasama sa sistema ng kontrol ng makina ang mga sumusunod na function ng kontrol ng sistema.

● Sistema ng kontrol ng pagpainit

● Rotary output ng makina

● Pag-andar ng komunikasyon at self-diagnosis

Elektronikong kinokontrol na fuel injection system (common rail type)

Ang common rail system ay nilagyan ng pressure chamber at injector. Ang pressure chamber ay dinisenyo upang mag-imbak ng pressurized fuel at tinatawag na common rail; ang injector ay nilagyan ng electronic control solenoid valve upang mag-inject ng pressurized fuel sa combustion chamber. Dahil ang injection control (ang injection pressure, injection rate at injection time) ay kinokontrol ng ECM, pinapayagan ng common rail system ang independent control ng engine speed at load. Kahit na mababa ang engine speed, ang matatag na injection pressure ay maaaring mapanatili, na lubos na magbabawas sa partikular na itim na usok sa pagsisimula at pagpapabilis ng diesel engine. Sa pamamagitan ng kontrol na ito, ang gas ng tambutso ay magiging malinis, ang dami ng gas ng tambutso ay magiging mas kaunti at ang output ay magiging mas mataas.

Kontrol ng dami ng iniksyon

Kinokontrol nito ang injector winding ayon sa signal na nakuha mula sa engine speed at accelerator pedal opening at dahil dito kinokontrol ang dami ng iniksyon ng gasolina upang makamit ang pinakamahusay na dami.

Kontrol ng presyon ng iniksyon

Upang payagan ang high pressure injection kahit na mababa ang engine speed, ang fuel pressure sa loob ng common rail ay dapat na kontrolin. Gumawa ng angkop na presyon sa common rail ayon sa engine speed at dami ng iniksyon ng gasolina, ilabas ang tamang dami ng gasolina sa pamamagitan ng control injection pump at pakainin ito sa common rail sa ilalim ng presyon.

Kontrol ng oras ng iniksyon

Pinapalitan nito ang timing function at gumagawa ng angkop na oras ng iniksyon ng gasolina ayon sa engine speed at dami ng iniksyon at pagkatapos ay kinokontrol ang injector.

Kontrol ng rate ng iniksyon

Upang mapahusay ang kahusayan ng pagkasunog ng silindro, mag-inject (pre-injection) ng kaunting gasolina para sa pag-aapoy. Pagkatapos ng pag-aapoy, isagawa ang pangalawang iniksyon (pangunahing iniksyon). Kontrolin ang oras ng iniksyon at dami ng iniksyon sa pamamagitan ng injector (ang injector coil).

Sistema ng Gasolina

Ang common rail system ay binubuo ng 2 fuel pressure system.

● Mababang presyon ng inlet line: sa pagitan ng fuel tank at injection pump

● Mataas na presyon ng linya: sa pagitan ng injection pump at injector

Ang gasolina ay sinisipsip sa injection pump mula sa fuel tank at pinalakas sa pump upang magbigay ng supply sa common rail. Sa puntong ito, ang signal mula sa ECM ay kumokontrol sa suction control valve (ang common rail pressure regulator) upang kontrolin ang dami ng gasolina na ibinibigay sa common rail.

Diagram ng sistema ng gasolina

EGR (Exhaust gas recirculation)

Ibinabalik muli ng sistema ng EGR ang isang bahagi ng gas ng tambutso sa intake manifold at dahil dito binabawasan ang paglabas ng nitrogen oxides (NOx). Sa pamamagitan ng sistema ng EGR, ang driving operability at pagbawas ng paglabas ng gas ng tambutso ay maaaring makamit. Ang control current mula sa EGR ay kumokontrol sa solenoid valve upang gumana at dahil dito kinokontrol ang EGR valve lift. Bukod pa rito, tinutukoy ng sistemang ito ang aktwal na valve lift gamit ang EGR position sensor upang mapagtanto ang pinong kontrol sa EGR.

Magsisimula ang EGR na gumana kapag ang mga kondisyon ng engine speed, engine coolant temperature, intake temperature at barometric pressure ay natugunan. Pagkatapos nito ay gagawa ito ng valve opening ayon sa engine speed at target fuel injection volume. Batay sa kinakalkulang valve opening, magpapasiya ito ng solenoid valve drive load at pagkatapos ay paandarin ang valve. Ang air intake throttle ay isasara sa panahon ng operasyon ng EGR upang paganahin ang presyon sa loob ng intake manifold na maabot ang target na halaga.

Kontrol ng pagpainit

Sistema ng kontrol ng pagpainit

Ang sistema ng kontrol ng pagpainit ay dinisenyo upang mapagaan ang pagsisimula ng makina sa mababang temperatura at bawasan ang puting usok at ingay. Sa aktibong starter switch, tinutukoy ng ECM ang engine coolant temperature ayon sa signal mula sa engine coolant temperature (ECT) sensor upang ayusin ang oras ng pagpainit at makamit ang angkop na mga kondisyon ng pagsisimula para sa makina. Bukod pa rito, ang natitirang init ng pagpainit ay maaaring mapanatili ang idling na matatag. Nagpapasiya ang ECM ng oras ng pagpainit ayon sa engine coolant temperature upang paandarin ang warming-up relay at indicator lamp upang gumana.

Pangkalahatang-ideya ng kontrol ng exhaust brake

Ang exhaust brake exhaust pipe ay nilagyan ng valve sa loob. Ang pagsasara ng valve ay maaaring magpataas ng pagtutol ng exhaust stroke at mapahusay ang epekto ng engine brake. Ang exhaust brake valve ay gumagana ayon sa vacuum pressure. Ang exhaust brake vacuum pressure ay kinokontrol ng pagbubukas at pagsasara ng solenoid valve. Paganahin ng ECM ang solenoid valve kung ang engine speed ay higit sa 575rpm at ang lahat ng mga kondisyon ng pagpapatakbo ng exhaust brake ay natugunan.

Mga kondisyon ng pagpapatakbo ng exhaust brake

● Naka-on ang exhaust brake switch

● Hindi pinindot ang accelerator pedal

● Hindi nakakakita ng abnormal na accelerator pedal position (APP) sensor, abnormal na exhaust brake circuit, abnormal na clutch switch, abnormal na APP sensor switch, abnormal na A/D switch, atbp.

● Hindi pinindot ang clutch pedal

● Ang boltahe ng sistema ay higit sa 24V

● Ang bilis ng sasakyan ay lumampas sa tinukoy na hanay

ECM

Pangkalahatang-ideya ng ECM

Patuloy na sinusubaybayan ng ECM ang impormasyon mula sa bawat sensor upang kontrolin ang power train. Ginagawa ng ECM ang function ng system diagnostic upang makita ang problema sa operasyon ng system, paalalahanan ang driver sa pamamagitan ng engine MIL at i-record ang DTC nang sabay. Tinutukoy ng DTC ang lugar ng problema upang matulungan ang maintenance man.

Mga function ng ECM

Nag-e-export ang ECM ng 5V boltahe upang pakainin ang iba't ibang sensor at switch. Gayunpaman, dahil ang kapangyarihan ay ibinibigay ng ECM resistance, ang test lamp na konektado sa circuit ay hindi magsisindi kahit na ang resistance ay napakataas. Sa ilang kaso, ang karaniwang voltmeter ay hindi makapagpapakita ng tamang pagbabasa dahil ang resistance nito ay napakababa. Upang maipakita ang tamang pagbabasa, tiyaking gumamit ng digital multimeter ng hindi bababa sa 10MΩ input impedance (5-8840-2691-0). Kinokontrol ng ECM ang ground circuit o power circuit sa pamamagitan ng transistor o iba pang yunit at dahil dito kinokontrol ang output circuit.

ECM at mga bahagi ng komposisyon

Ang ECM ay maaaring makamit ang mataas na steerability at fuel efficiency habang pinapanatili ang tinukoy na paglabas ng gas ng basura. Sinusubaybayan ng ECM ang pagganap ng engine at sasakyan sa pamamagitan ng crankshaft position (CK

ECM voltage description

ECM applies the standard voltage to each switch and sensor. This is because the ECM resistance is very high while the voltage applied to the circuit is low. The test lamp will not illuminate even if connected in the circuit. Since the input impedance of voltmeter generally used by the maintenance man is very low, sometimes the voltmeter cannot display the correct reading. In such a case, use digital multimeter of 10MΩ input impedance (5- 8840 -2691-0) to get the correct voltage reading.

The ECM input/output unit is equipped with analog-digital converter, signal damping, counter and special actuator. ECM can control most composition parts through the electronic switch.

EEPROM

EEPROM is permanent storage chip soldered to the ECM back plate. To control the power train, ECM transmits the necessary program and calibration message to EEPROM.

Different from ROM, EEPROM cannot be replaced. If EEPROM is detected abnormal, replace the ECM directly.

Considerations for ECM repair

ECM can withstand the general current relevant to vehicle driving. Do not allow the circuit overload. During the open circuit and short circuit test, do not connect the ECM circuit to the ground wire or apply the voltage unless otherwise specified. For such circuit tests, ensure to use the digital multimeter (5-8840-2691-0).

The injection pump is the core part of common rail electronic fuel injection system. The injection pump is installed to the engine front. The common rail pressure regulator and fuel temperature (FT) sensor are the composition parts of the injection pump.

The fuel is fed to the injection pump from the fuel tank through the inside supply pump (rotor type). The supply pump feeds the fuel into 2 plunger compartments in the injection pump. The fuel fed to the plunger compartment is regulated by the common rail pressure regulator. The common rail pressure regulator is only controlled by the ECM supply current. The fuel flow will reach the maximum if no current is fed to the solenoid valve. Contrarily, the fuel will stop flowing when the solenoid valve current reaches the maximum. As the engine rotates, the two plungers build high pressure in the common rail. It controls the common rail pressure regulator according to the ECM signal and consequently controls the fuel volume and pressure to the common rail. In this way, the optimal operating state can be realized to enhance the fuel economical efficiency and reduce the NOx emission.

Key

1. Fuel temperature (FT) sensor

Suction control valve (common rail pressure regulator)

ECM controls the load factor of common rail pressure regulator (the power-on time of common rail pressure regulator) to regulate the fuel volume fed to the high pressure plunger. To achieve the desired rail pressure, feed the proper amount of fuel to reduce the drive load of the injection pump. When the current is fed to the common rail pressure regulator, the variable electromotive force corresponding to the load factor will be generated to vary the fuel line opening and consequently adjust the fuel volume. When the common rail pressure regulator is switched off, the retracting spring will retract, the fuel line will completely open and the fuel will flow to the plunger (the maximum intake and maximum discharge). With the common rail pressure regulator open, the fuel line will close (normally open) under the function of the retracting spring. Through the open and close of common rail pressure regulator, the fuel corresponding to the working load rate will be supplied and then discharged from the plunger.

Fuel temperature (FT) sensor

FT sensor is installed to the injection pump and the thermistor changes the resistance along with the temperature variation. The resistance will be low if the fuel temperature is high and high if the fuel temperature is low. ECM applies 5V voltage to FT sensor through the load resistor and works out the fuel temperature according to the voltage variation to control the injection pump. The voltage will be low if the resistance is low (the temperature is high) and high if the resistance is high (the temperature is low).

Common rail

Key

1. Pressure limiting valve

Due to the common rail type electrical control fuel injection system, the common rail is provided between the injection pump and injector to store the high pressure fuel. The pressure sensor and pressure limiting valve are installed on the common rail. The pressure sensor detects the fuel pressure in the common rail and transmits the signal to ECM. Basing on this signal, ECM controls the fuel pressure in the common rail with the injection pump common rail pressure regulator. If the common rail inside fuel pressure is too high, the pressure limiting valve will open to release the pressure.

Common rail pressure sensor

The common rail pressure sensor is installed to the common rail to detect the fuel pressure in the rail and convert the pressure into voltage signal. The higher the pressure, the higher the voltage; the lower the pressure, the lower the voltage. ECM works out the actual common rail pressure (the fuel pressure) according to the voltage signal from the sensor to control the fuel injection.

Pressure limiting valve

Key

1. Valve

2. Valve body

3. Valve guide

4. Spring

5. Housing

6. Fuel inlet

In the case of abnormal high pressure, the pressure limiting valve will open to release the pressure. The valve will open when the common rail inside pressure exceeds 220MPa and close when the pressure is below 50MPa. The fuel discharged from the pressure limiting valve will flow to the fuel tank.

Injector

Key

1. Wiring bolt

2. Return to the pipeline installation department

3. O-ring

4. Injection pipe installation part

5. Identification marking

Compared to the earlier injection nozzle, the electrical control injector controlled by ECM is provided with command piston and solenoid valve. This information is recorded in the ID code (24 English numbers) to display the injector characteristics. This system controls the injection volume to achieve the optimal effect with the injector flow information (ID code). When a new injector is installed to the vehicle, ensure to enter ID code in ECM.

To enhance the injection volume accuracy, use the 2D bar code or ID code on the injector. With the code, the decentralized control injection volume can be achieved on each pressure zone to enhance the combustion rate, reduce the exhaust and provide the stable output .

● Without injection

If ECM does not power the solenoid valve through the two-way valve (TWV), it will close the outlet throttling orifice with the piston force. At this point, the fuel pressure applied to the nozzle front end will be balance with the fuel pressure applied to control room through the inlet. In this pressure balance state, the sum of pressure applied to command piston and nozzle piston gravity will be higher than the pressure applied to the nozzle front end. Therefore, the nozzle will be pushed down to close the injection hole.

● Injection

If ECM powers the solenoid valve, TWV will be pulled to open the outlet throttling orifice and the fuel will flow to the oil return port. At this point, the nozzle and command piston are lifted together with the pressure applied to the nozzle front end. Then the nozzle injection hole will open to inject the fuel.

● Injection end

When the ECM stops powering the solenoid valve, TWV will fall and the outlet opening part will close. At this point, the fuel cannot flow to the return port from the control room and the fuel pressure inside will rise quickly. Then the nozzle will be depressed by the command piston to close the injection port and then the fuel injection will stop.

Engine coolant temperature (ECT) sensor

ECT sensor is installed near the thermostat shell and the thermistor changes the resistance along with the temperature variation. The resistance will be lower if the engine coolant temperature is high and high if the engine coolant temperature is low. ECM applies 5V voltage to ECT sensor through the load resistor and works out the engine coolant temperature according to the voltage variation to control the fuel injection. The voltage will be low if the resistance is low (the temperature is high) and high if the resistance is high (the temperature is low).

Camshaft position (CMP) sensor

Key

1. Camshaft gear

2. Rotation direction

The camshaft position (CMP) sensor is installed to the cylinder head rear section. The cam section of the camshaft generates the CMP signal when passing through the sensor. ECM determines the cylinder conditions and crankshaft angle according to the CMP signal and CKP sensor input CKP signal to control the fuel injection and calculate the engine speed. Though these controls base on CKP signal in general, they will work according to the CMP signal in the case of CKP sensor abnormal.

Crankshaft position (CKP) sensor

Key

The CKP sensor is installed to the flywheel housing. When the flywheel hole passes through the sensor, it will generate CKP signal. ECM determines the cylinder conditions and camshaft angle according to the CKP signal and CMP sensor input CMP signal to control the fuel injection and calculate the engine speed. Though these controls base on CKP signal in general, they will work according to the CMP signal in the case of CKP sensor abnormal.

Accelerator pedal position (APP) sensor 1

APP sensor is installed to the accelerator pedal control bracket. This sensor consists 2 sensors in one shell. ECM determines the acceleration and deceleration target value with the APP sensor. APP sensor is pin hole 1C type sensor. The signal voltage changes along with the accelerator pedal angle variation proportionably. APP sensor 1 signal voltage is low at in the early stage and increases as the pedal depressed. APP sensor 2 signal voltage is high at in the early stage and decreases as the pedal depressed.

Vehicle speed sensor

The vehicle speed sensor (VSS) is installed to the transmission. The vehicle speed sensor is equipped with HALL effect circuit. The magnet and output shaft generate the magnetic field when rotating together and then generate the pulse signal through the interaction with the magnetic field.

Atmospheric pressure sensor

The barometric pressure sensor is installed to the dashboard and changes the signal voltage along with the pressure. ECM detects the low signal voltage when the pressure is low in the high elevation area; contrarily, it detects the high signal voltage when the pressure is high. With these voltage signals, ECM can regulate the fuel injection volume and injection time to correct the elevation.

Intake air temperature (IAT) sensor

Intake air temperature (IAT) sensor

IAT sensor is installed to the guide tube between the air filter and turbocharger. When the IAT sensor temperature is low, the sensor resistance will be high. When the air temperature increases, the sensor resistance will be lower. When the sensor resistance is high, ECM will detect the high voltage on the signal circuit. When the sensor resistance is low, ECM will detect the low voltage on the signal circuit.

EGR valve

EGR valve is installed to the intake manifold. ECM controls the opening of EGR valve according to the engine operating state. According to the duty ratio signal from ECM, it controls the magnetic coil in EGR valve. Through the position sensor, it can detect the EGR valve opening. The position sensor is provided with 3 sensors in EGR valve to detect 3 locations respectively. Position sensors 1, 2, 3 are pin hole 1C type. The position sensor exports the valve open/close state in form of signal, which is in proportion with the variation of EGR valve opening.

Intake pressure sensor

The intake air pressure sensor is installed to the air inlet duct to detect the intake air pressure and convert the pressure into voltage signal. ECM detects high voltage when the pressure is high. It detects low voltage when the pressure is low. ECM works out the intake air pressure according to the voltage signal from the sensor to control the fuel injection and turbocharger.

Engine malfunction warning lamp

The engine malfunction warning lamp is installed inside the instrument to remind the driver of the engine or related system abnormal. When ECM detects abnormal through the self-diagnosis function, the engine malfunction warning lamp will be on. Short the data link connector (DLC) terminals to make the engine malfunction warning lamp blink. Then the DTC detecting state can be confirmed.

Data Link Connector (DLC)

DLC is installed to the lower left of the driver and it is the communication connector for the fault diagnostic meter and each control unit. It is provided with the diagnosis switch function. Through the short-circuit of DLC, it can enable the diagnosis switch.

Parts configuration diagram

Engine composition parts layout

(1/2)

(2/2)

Key

1. Crankshaft position (CKP) sensor

Engine composition parts layout 1

Key

1. ECM

Engine composition parts layout 3

Circuit diagram

Circuit diagram sketch (1/2)

(2/2)

Terminal arrangement