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Home >> Infiniti >> 2024 >> Q50 Luxe, AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (2 Of 2) >> Description >> System >> Engine Control System >> Fail-safe >> Fail-safe (Turbo high pressure models)
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Fail-safe (Turbo high pressure models)

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) and device fix mode.

Fail safe mode Vehicle behavior
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.
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.
  • Engine output control 1: Driving at 70 km/h or more is possible.
  • Engine output control 2: Driving at 40 km/h 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.
Device fix mode
  • Fixes electric intake valve timing control motor in the reference position.
  • Fixes exhaust valve timing control solenoid valve in the reference position.
Combustion control mode Stratified charge combustion control at starting No stratified charge combustion at starting (cold start).
Idle speed control Stops feedback control of idle speed and controls with specified speed.
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.
Retardation control Controls ignition timing delay control in the intermediate water temperature range.

Fail Safe Pattern 

Pattern Fail safe mode
A Traveling control mode Accelerator angle variation control
B Engine output control 1
C Engine output control 2
D Device fix mode
E Combustion control mode Stratified charge combustion control at starting
F
  • Idle speed control
  • Recovery speed control at decelerating
  • Idle neutral control*
G
  • Ignition timing correction control
  • Retardation control

*: Not applicable

Fail Safe List 

x: Applicable -: Not applicable

DTC No. Detected items Vehicle behavior
Pattern Others
A B C D E F G
U0122 CAN communication line x - - - x - - -
U012E
U042F
Engine communication - - - x x - - ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)
- - - x - x -
P0010
P0020
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 -
P0011
P0012
P0021
P0022
Intake valve timing control - - - x - - - ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)
NOTE: When VTC mechanism sticks, camshaft position does not change from position of stuck angle.
P0016
P0018
- - - - - - -
P0014
P0015
P0017
P0019
P0024
P0025
Exhaust valve timing control - - - x - - - -
P0046
P004B
Electric wastegate actuator motor - x - x - - - ECM stops the electric wastegate actuator control. (Wastegate valve opens)
P0078
P0084
Exhaust valve timing control solenoid valve - - - x - - - -
P0087
P0088
Fuel rail pressure control x - - x x - - -
x - - - x - -
P0090 High pressure fuel pump x - - x x - - -
P0101
P010B
Mass air flow sensor x - - - x - - -
- x - x - - x -
P0102
P0103
P010C
P010D
- x - x - - x -
P0117
P0118
Engine coolant temperature sensor - - - - - x - -
P0122
P0123
P0222
P0223
P0227
P0228
P1239
P2132
P2133
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
P0174
P0175
Fuel injection system x - - - - x - -
P0190 Fuel rail pressure sensor x - - x - x - -
P0191
P0192
P0193
x - - - x - - -
P0197
P0198
Engine oil temperature sensor - - - - - - - Exhaust valve timing control does not function.
P0201
P0202
P0203
P0204
P0205
P0206
Fuel injector x - - - x - - -
P0234
P1334
Turbocharger system - x - x - - - -
P0235
P0237
P0238
P0241
P0242
Turbocharger boost sensor - x - x - - - -
P0300
P0301
P0302
P0303
P0304
P0305
P0306
Misfire x - - - - x - -
P0335 Crankshaft position sensor - - - x x - - -
- - - x - x -
P0340
P0345
Intake camshaft position sensor - - - x x - - -
- - - x - x -
P1140
P1145
x - - x - - x -
P0365
P0390
Exhaust camshaft 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
P0607
ECM - - - - - - - -
- x - - - - - ASCD operation may be deactivated.
P0604 - - - x - - - 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 - - - ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
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.
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 - -
P062D
P062E
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 - - - -
P14A4
P14A5
P14AD
P14AE
Charge air cooler cooling electric water pump - - - - - - - Charge air cooler cooling electric water pump runs at the command speed.
P14A7
P14B0
- - - - - - - Charge air cooler cooling electric water pump runs at full speed.
P14A9
P14AA
P14AC
P14B2
P14B3
P14B5
- - - - - - - Charge air cooler cooling electric water pump stops.
P1197 Out of gas - - - x - - - -
P119A
P119B
P119C
Fuel pressure sensor x - - - x - - -
P1233
P2101
Electric throttle control - - - x - - - ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P1236
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.
P1238
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.
P1290
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.
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
P2122
P2123
P2127
P2128
P2138
Accelerator pedal position sensor - - - x - - - -
P23E9
P23EA
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.)
- - - x - x -
P23EB
P2616
P2617
P2618
- - - x x - -
P2619 - - - x - x -
P2562
P2566
P2586
P2590
Electric wastegate control valve position sensor - x - x - - - ECM stops the electric wastegate actuator control. (Wastegate valve opens)
P2563
P2564
P2565
P2587
P2588
P2589
-
P2578
P2593
Turbocharger speed sensor - - - - - - - Torque have to be limited to the operating range that does not generate the over speed of the turbocharger.
P25DF
P25E8
P34AC
P34AD
P34B0
P34B1
Electric intake valve timing control actuator - - - x x - - ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)
NOTE: Normal bank transitions intermediate F/S valve timing.
P34C4
P34C5
Electric intake valve timing control actuator - - - x x - - ECM stops the electric valve timing control. (The camshaft returns to the position of most retard angle.)
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 -