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Home >> Infiniti >> 2019 >> QX50 Essential, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (2 Of 6) >> System >> Fail-safe >> Engine Control System
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Engine Control System

Description 

When a DTC is detected, ECM executes a mode (in the Fail-safe mode) applicable to the DTC. The fail-safe mode has the preset traveling control mode (accelerator angle variation and engine output limit), device fix mode and combustion control mode.

Fail safe mode

Vehicle behavior

Fail safe pattern

Traveling control mode

Accelerator angle variation control

ECM controls the accelerator pedal depression speed to make it slower than actual speed. This causes a drop in accelerating performance and encourages the driver to repair malfunction.

NOTE: ECM does not control the accelerator pedal releasing speed.

A

Engine output control 1

ECM reduces the engine output, according to the rise in engine speed. This reduces the vehicle speed to encourage the driver to repair malfunction.

Driving at 70 km/h (44 MPH) or more is possible.

NOTE: This value is a reference value converted from engine power to vehicle speed. Actual power limitation value differs due to the malfunctioning part and driving condition.

B

Engine output control 2

ECM reduces the engine output, according to the rise in engine speed. This reduces the vehicle speed to encourage the driver to repair malfunction.

Driving at 40 km/h (25 MPH) or more is possible.

NOTE: This value is a reference value converted from engine power to vehicle speed. Actual power limitation value differs due to the malfunctioning part and driving condition.

C

Device fix mode

  • This mode fixes the EVT control solenoid valve in the reference position.
  • The intake manifold runner control valve motor is turned OFF (intake manifold runner control valve opens).

D

Combustion control mode

Stratified charge combustion control at starting

No stratified charge combustion at starting (cold start).

E

Idle speed control

Stops feedback control of idle speed and controls with specified speed.

F

Recovery speed control at decelerating

Stops recovery speed control by the fuel cut at decelerating and controls with specified speed.

Ignition timing correction control

Partially controls ignition timing control.

G

Retardation control

Controls ignition timing delay control in the intermediate water temperature range.

Fail Safe List 

x:Applicable --: Not applicable

DTC No.

Detected items

Vehicle behavior

Pattern

Others

A

B

C

D

E

F

G

P0010

Electric intake valve timing module

--

--

--

x

x

--

--

ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)

--

--

--

x

--

x

--

P0011

P0012

Intake valve timing control

--

--

--

x

--

--

--

ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)

P0014

P0015

Exhaust valve timing control

--

--

--

x

--

--

--

--

P0046

Wastegate control actuator

--

x

--

x

--

--

--

P0078

Exhaust valve timing control solenoid valve

--

--

--

x

--

--

--

--

P0087

P0088

FRP control system

x

--

--

x

x

--

--

--

x

--

--

--

x

--

--

P0090

x

--

--

x

x

--

--

P0101

Mass air flow sensor circuit

x

--

--

--

x

--

--

--

--

x

--

x

--

--

x

P0102

P0103

--

x

--

x

--

--

x

--

P0117

P0118

Engine coolant temperature sensor circuit

--

--

--

--

--

x

--

--

P0122

P0123

P0222

P0223

P2135

Throttle position sensor

--

--

--

x

--

--

--

The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10 degrees.

The ECM regulates the opening speed of the throttle valve to be slower than the normal condition. So, the acceleration will be poor.

NOTE: If throttle position sensor 1 and 2 malfunction at the same time conducts following control.
  • ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P0171

P0172

Direct fuel injection system

x

--

--

--

--

x

--

--

P0190

FRP sensor

x

--

--

x

--

x

--

--

P0191

P0192

P0193

x

--

--

--

x

--

--

--

P0196

P0197

P0198

Engine oil temperature sensor

--

--

--

--

--

--

--

Intake and exhaust valve timing control does not function.

P0201

P0202

P0203

P0204

Direct fuel injector

x

--

--

x

x

--

--

--

P0235

Turbocharger boost sensor

--

x

--

x

--

--

--

--

P0237

P0238

P0261

P0264

P0267

P0270

Direct fuel injector

x

--

--

x

x

--

--

P0262

P0265

P0268

P0271

x

--

--

x

x

--

--

P0300

P0301

P0302

P0303

P0304

Misfire

x

--

--

--

--

x

--

--

P0335

Crankshaft position sensor

--

--

--

x

--

x

--

--

--

--

--

x

x

--

--

--

--

--

x

--

--

--

P0340

Camshaft position sensor

--

--

--

x

--

x

--

--

--

--

--

x

x

--

--

--

--

--

x

--

--

--

P0365

Exhaust valve timing control position sensor

--

--

--

x

--

--

--

--

P0500

Vehicle speed sensor

x

--

--

--

--

x

--

--

P0524

Engine oil pressure

--

--

--

--

--

--

--

  • ECM illuminates engine oil pressure warning lamp on the combination meter.
  • Engine speed will not rise more than 4, 000rpm due to the fuel cut.
  • Fail-safe is canceled when ignition switch OFF -> ON.

P0603

ECM

--

x

--

--

--

--

--

--

P0604

P060B

--

--

--

x

--

--

--

(Computing part of ECM does not operate normally.)

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P0605

--

--

--

--

--

--

--

--

--

--

--

x

--

--

--

(Computing part of ECM does not operate normally.)

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring. *1

P0606

--

--

--

--

--

--

--

--

--

--

--

x

--

--

--

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P0607

--

--

--

--

--

--

--

--

--

x

--

--

--

--

--

ASCD operation may be deactivated.

P060A

--

--

--

x

--

--

--

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

--

x

--

x

--

--

--

  • ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
  • ASCD operation may be deactivated.

P060B

--

--

--

x

--

--

--

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P062B

--

--

--

--

--

--

--

--

x

--

--

x

x

--

--

P062D

x

--

--

x

x

--

--

P0641

Sensor power supply

--

--

--

x

--

x

--

ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)

--

--

--

x

x

--

--

P0643

--

--

--

x

--

--

--

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P10C0

Direct fuel injector

x

--

--

x

x

--

--

P10C8

P10C9

P10CA

P10CB

Direct fuel injector

x

--

--

x

x

--

--

P1197

Out of gas

--

--

--

x

--

--

--

Engine torque is limited.

P11A0

VCR control module

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

P11A1

VCR motor

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

P11A2

VCR motor rotation angle sensor

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

P11A3

Variable compression ratio motor resolver

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

P11A4

VCR motor rotation angle sensor

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

P11A6

VCR rotation angle sensor mutual

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

P11A7

VCR stopper position

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

P11AA

VCR position learning

--

--

--

--

--

--

--

Fix low compression ratio

P11AB

VCR control module circuit

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

    These fail-safe may not be executed.

P11AC

P11AD

P11AE

P11AF

VCR shaft 2 rotation angle sensor

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF

P1217

Engine over temperature

--

--

--

--

--

--

--

Engine speed is limited due to the fuel cut.

P1805

Brake switch

--

--

--

--

--

--

--

ECM controls the electric throttle control actuator by regulating the throttle opening to a small range.

Therefore, acceleration will be poor.

Vehicle condition

Driving condition

When engine is idling

Normal

When accelerating

Poor acceleration

P2004

Intake manifold runner control valve

--

x

--

x

x

--

--

--

P2014

P2016

P2017

P2018

Intake manifold runner control valve position sensor

--

--

--

x

--

--

--

--

P2100

P2103

Throttle control motor relay

--

--

--

x

--

--

--

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P2101

Electric throttle control function

--

--

--

x

--

--

--

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P2118

Throttle control motor

--

--

--

x

--

--

--

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P2119

Electric throttle control actuator

--

x

--

--

--

--

--

--

--

--

--

x

--

--

--

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

NOTE: For pattern A and B refer to A and B of P2119 DTC detection logic. (Refer to DTC Description .)

For C of P2119 DTC detection logic ECM behaves as above.

P2122

P2123

P2127

P2128

P2138

Accelerator pedal position sensor

--

--

--

x

--

--

--

The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10 degrees.

The ECM regulates the opening speed of the throttle valve to be slower than the normal condition. Therefore, the acceleration will be poor.

NOTE: If accelerator pedal position sensor 1 and 2 malfunction at the same time conducts following control.
  • ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.

P21CF

P21D0

P21D1

P21D2

P21DB

P21DE

P21E0

P21E2

P21DC

P21DF

P21E1

P21E3

Port fuel injector

x

--

--

x

x

--

--

--

P21F4

P21F5

Fuel system

x

--

--

--

--

x

--

--

P2562

P2566

Electric wastegate control valve position sensor

--

x

--

x

--

--

--

The ECM stops the electric wastegate actuator control, engine can not be supercharged driving.The ECM requlates engine power limiter and EGR Off.

P2563

P2564

P2565

Electric wastegate control valve position sensor

--

x

--

x

--

--

--

--

P2578

Turbocharger speed sensor

--

--

--

--

--

--

--

Torque have to be limited to the operating range that does not generate the over speed of the turbocharger.

P2614

P2615

Intake camshaft position sensor

--

--

--

x

--

x

--

ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)

P2616

--

--

--

x

x

--

--

P2617

Crankshaft position sensor

--

--

--

x

x

--

--

ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)

P2618

--

--

--

x

x

--

--

P2619

--

--

--

x

--

x

--

P26A3

P26A5

P26A6

P26A7

Multi-way control valve

--

--

--

--

--

--

--

  • When detecting a malfunction with the valve closed, ECM fully opens the valve.
  • When detecting a malfunction with the valve opened, ECM maintains valve angle.
  • When detecting a malfunction in sensor, ECM fully opens the valve.
  • ECM limits the engine output depending on malfunctions.

P34AC

P34AD

Electric intake valve timing control actuator

--

--

--

x

x

--

--

--

--

--

--

x

x

--

--

--

P34AE

P34AF

Electric intake valve timing control position sensor

--

--

--

x

x

--

--

--

P34C8

Electric intake valve timing control module

--

--

--

x

x

--

--

ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)

--

--

--

x

x

x

--

U012E

U042F

CAN communication line

--

--

--

x

--

x

--

ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)

--

--

--

x

x

--

--

U10A0

Lost communication (Variable compression ratio)

--

--

--

--

--

--

--

  • Engine speed limited
  • Stop turbocharger boost control
  • VCR motor OFF