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Home >> Nissan-Datsun >> 2023 >> Altima SL, FWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (Pr25DD) (1 Of 2) >> System Description >> System >> Engine Control System >> Fail-safe
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Engine Control System: Fail-safe

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: SYMBOL ECM does not control the accelerator pedal releasing speed.
A
Engine output control 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.
  • Driving at 40 km/h (25 MPH) or more is possible.
NOTE: SYMBOL 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
Device fix mode
  • This mode fixes the electric IVT motor and 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).
  • A control signals is not transmitted to EGR volume control valve and the EGR volume control is deactivated.
C
Combustion control mode Stratified charge combustion control at starting No stratified charge combustion at starting (cold start). D
Idle speed control Stops feedback control of idle speed and controls with specified speed. E
Recovery speed control at decelerating Stops recovery speed control by the fuel cut at decelerating and controls with specified speed.
Idle neutral control Stops idle neutral control.
Ignition timing correction control Partially controls ignition timing control. F
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
U0101 CAN communication line - - - - - - ECM operates active grille shutter to fully-open position.
U0122 CAN communication line x - - x - - -
U012E, U042F - - x x - - ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)
- - x x x -
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 x -
P0011, P0012, P052A, P052B Intake valve timing control - - - - - x
P0014, P0015, P0017, P054A, P054B Exhaust valve timing control - - x - - - -
P0078 Exhaust valve timing control solenoid valve - - x - - - -
P0087, P0088, P0090 FRP control system x - x x - - -
x - - x - -
P0101 Mass air flow sensor circuit x - - x - - -
x x x x x x
P0102, P0103 x x x x x x -
P0117, P0118 Engine coolant temperature sensor circuit - - - x 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.
P0171, P0172 Fuel injection system x - - x x - -
P0190 FRP sensor x - x x x - -
P0191, P0192, P0193, P119A, P119B, P119C x - - x - - -
P0201, P0261, P0262 Direct fuel injector x - x x - - -
P0300 Misfire x - - x x - -
P0335 Crankshaft position sensor - - x x - - -
- - x x x -
- - x - - -
P0340 Intake camshaft position sensor - - x x - - -
- - x x x -
- - x - - -
P0365 Exhaust camshaft position sensor - - x - - - -
P0401, P0402 EGR volume control valve - - x - - - -
P0404 x x x x x -
P044A, P044B, P044C, P044D, P044E EGR volume control valve position sensor x - x - - - -
P0500 Vehicle speed sensor x - - x x - -
P0603, P0607 ECM x x - - - - -
- - - - - -
P0606 - - - - - - -
- - x - - -
P060A x x x - - - -
- - x - - -
P060B - - x - - - -
P061B - - 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 - -
NOTE: SYMBOL Fail-safe mode may not start depending on malfunction type of ECM.
- - - - - -
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 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 Direct fuel injector x - x x - - -
P1197 Out of gas - - x - - - Engine torque is limited.
P2004 Intake manifold runner control valve - - x - - - -
P2008 x x x x x x -
P2014, P2015 Intake manifold runner control valve position sensor - - x - - - -
P2016, P2017, P2018 - - 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 - - - - -
- - x - - -
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.
P2413 EGR volume control valve x - x - - - -
P2614, P2615 Intake camshaft position sensor - - x x x - ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)
- - x x - -
P2616 - - x x - -
P2617, P2618 Crankshaft position sensor - - x x - - ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)
P2619 - - x x x -
P34AC Electric intake valve timing control actuator - - x x - - -
P34AD - - x x - - -
P34AE Electric intake valve timing control position sensor - - x x - - -
P34AF - - 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 -

STOP/START SYSTEM 

Description 

When a DTC is detected, the stop/start indicator lamp blinks slowly and the stop/start system operation is prohibited. When ECM detects error while operating the stop/start system, ECM restarts the engine. Check each DTC code and perform inspection and repair work in accordance with each trouble diagnosis procedure. Refer to DTC Index .