Nissan Altima L32. Manual - part 473
ECM
EC-1013
< ECU DIAGNOSIS >
[QR25DE EXCEPT FOR CALIFORNIA]
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EC
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DTC RELATED ITEM
Engine operating condi-
tion in fail-safe mode
Detected items
Remarks
Reference
page
Engine speed will not
rise more than 2,500 rpm
due to the fuel cut
Malfunction indicator
lamp circuit
When there is an open circuit on MIL circuit, the ECM cannot warn the
driver by lighting up MIL when there is malfunction on engine control
system.
Therefore, when electrical controlled throttle and part of ECM related
diagnoses are continuously detected as NG for 5 trips, ECM warns the
driver that engine control system malfunctions and MIL circuit is open
by means of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MIL
circuit are detected and demands the driver to repair the malfunction.
DTC No.
Detected items
Engine operating condition in fail-safe mode
P0011
Intake valve timing control
The signal is not energized to the intake valve timing control solenoid valve and the valve
control does not function.
P0102
P0103
Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118
Engine coolant tempera-
ture sensor circuit
Engine coolant temperature will be determined by ECM based on the following condition.
CONSULT-III displays the engine coolant temperature decided by ECM.
Condition
Engine coolant temperature decided
(CONSULT-III display)
Just as ignition switch is turned ON
or START
40
°C (104°F)
More than approx. 4 minutes after
engine starting
80
°C (176°F)
Except as shown above
40 - 80
°C (104 - 176°F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling
fan operates while engine is running.
P0122
P0123
P0222
P0223
P2132
P2133
P2135
Throttle position sensor
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.
P0500
Vehicle speed sensor
The cooling fan operates (High) while engine is running.
P0643
Sensor power supply
ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P0605
ECM
(When ECM calculation function is malfunctioning:)
ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
ECM deactivates ASCD operation.
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
P2100
P2103
Throttle control motor relay 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
ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.