2005 INFINITI FX35 coolant temperature sensor

TROUBLE DIAGNOSIS EC-107
[VQ35DE]
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Revision: 2005 July 2005 FX
DTC Inspection Priority ChartABS006KP
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
If DTC U1000 and/or U1001 is displayed with other DTC, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-171
.
Priority Detected items (DTC)
1

U1000 U1001 CAN communication line

P0101 P0102 P0103 Mass air flow sensor

P0112 P0113 P0127 Intake air temperature sensor

P0117 P0118 P0125 Engine coolant temperature sensor

P0128 Thermostat function

P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor

P0181 P0182 P0183 Fuel tank temperature sensor

P0327 P0328 Knock sensor

P0335 Crankshaft position sensor (POS)

P0340 P0345 Camshaft position sensor (PHASE)

P0460 P0461 P0462 P0463 Fuel level sensor

P0500 Vehicle speed sensor

P0605 ECM

P0700 TCM

P0705 Park/Neutral position (PNP) switch

P1229 Sensor power supply

P1610 - P1615 NATS

P1706 Park/Neutral position (PNP) switch

P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor

TROUBLE DIAGNOSIS EC-109
[VQ35DE]
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Revision: 2005 July 2005 FX
Fail-Safe ChartABS006KQ
When the DTC listed below is detected, the ECM enters fail-safe mode and the MIL lights up.

When there is an open circuit on MIL circuit, the ECM cannot warn the driver by MIL lighting up 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
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 time after turning
ignition switch ON or START.
CONSULT-II displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned
ON or START 40
°C (104 °F)
More than approx. 4 minutes after
ignition ON or START 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
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.
P1121 Electric throttle control actuator (When electric throttle control actuator does not function properly due to the return spring
malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the
idle position. The engine speed will not rise more than 2,000 rpm.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator by regulating the throttle opening to 20
degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops,
the engine stalls.
The engine can restart in N or P position, and engine speed will not exceed 1,000 rpm or
more.
P1122 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.
P1124
P1126 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.
P1128 Throttle control motor ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P1229 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.
P2122
P2123
P2127
P2128
P2138 Accelerator pedal 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.
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut

EC-110
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
Symptom Matrix ChartABS006KS
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit 11232 22 3 2 EC-668
Fuel pressure regulator system334444444 4 EC-99
Injector circuit 11232 22 2 EC-661
Evaporative emission system 334444444 4EC-39
Air Positive crankcase ventilation sys-
tem 33 4444444 41
EC-51
Incorrect idle speed adjustment 1 1 1 1 1 EC-78
Electric throttle control actuator 112332222 2 2 EC-424,
EC-426
IgnitionIncorrect ignition timing adjustment33111 11 1 EC-78
Ignition circuit 11222 22 2EC-648
Power supply and ground circuit22333 33 23 EC-164
Mass air flow sensor circuit
1
12 2
222 2 EC-186,
EC-195
Engine coolant temperature sensor circuit
3 33
EC-208,
EC-220
Air fuel ratio (A/F) sensor EC-488
EC-497
EC-506
EC-516
EC-526
EC-536
EC-548
Throttle position sensor circuit
22 EC-213
,
EC-278
,
EC-479
,
EC-481
,
EC-633
Accelerator pedal position sensor circuit 3 2 1 EC-483
,
EC-619
,
EC-626
,
EC-640
Knock sensor circuit 2 3 EC-295
Crankshaft position sensor (POS) circuit 2 2EC-300
Camshaft position sensor (PHASE) circuit 3 2EC-307

TROUBLE DIAGNOSIS EC-129
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Revision: 2005 July 2005 FX66 B Sensor ground
(Throttle position sensor) [Engine is running]
Warm-up condition

Idle speed
Approximately 0V
67 B/W Sensor ground [Engine is running]

Warm-up condition

Idle speed Approximately 0V
68 BR Sensor power supply
(Power steering pressure
sensor) [Ignition switch: ON]
Approximately 5V
69 R Throttle position sensor 2 [Ignition switch: ON]

Engine stopped

Selector lever: D

Accelerator pedal: Fully released
Less than 4.75V
[Ignition switch: ON]

Engine stopped

Selector lever: D

Accelerator pedal: Fully depressed More than 0.36V
70 L/R Refrigerant pressure sensor [Engine is running]

Warm-up condition

Both A/C switch and blower switch are ON
(Compressor operates) 1.0 - 4.0V
73 Y Engine coolant temperature
sensor [Engine is running] Approximately 0 - 4.8V
Output voltage varies with
engine coolant temperature.
74 LG/B Heated oxygen sensor 2
(bank 1) [Engine is running]

Warm-up condition

Revving engine from idle to 3,000 rpm
quickly after the following conditions are met
–After keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at idle
for 1 minute under no load 0 - Approximately 1.0V
78 B/R Sensor ground
(Heated oxygen sensor) [Engine is running]

Warm-up condition

Idle speed
Approximately 0V
79
80
81 SB
GY
OR Ignition signal No. 6
Ignition signal No. 4
Ignition signal No. 2 [Engine is running]

Warm-up condition

Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idle 0 - 0.2V
[Engine is running]

Warm-up condition

Engine speed is 2,500 rpm 0.1 - 0.4V
TER-
MINAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
SEC986C
SEC987C

TROUBLE DIAGNOSIS EC-133
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Revision: 2005 July 2005 FX
ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
Item DIAGNOSTIC TEST MODE
WORK SUP-
PORT SELF-DIAGNOSTIC
RESULTS DATA
MONI-
TOR DATA
MONI- TOR
(SPEC) ACTIVE
TEST DTC & SRT
CONFIRMATION
DTC*1 FREEZE
FRAME
DATA*2 SRT
STATUS DTC
WORK SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS) ××××
Camshaft position sensor (PHASE) ××××
Mass air flow sensor ×××
Engine coolant temperature sensor ×××××
Air fuel ratio (A/F) sensor 1 ×××××
Heated oxygen sensor 2 ×××××
Vehicle speed sensor ××××
Accelerator pedal position sensor ×××
Throttle position sensor ×××
Fuel tank temperature sensor ××××
EVAP control system pressure
sensor ×××
Intake air temperature sensor ××××
Knock sensor ×
Refrigerant pressure sensor ××
Closed throttle position switch
(accelerator pedal position sensor
signal) ××
Air conditioner switch ××
Park/neutral position (PNP) switch ×××
Stop lamp switch ×××
Power steering pressure sensor ×××
Battery voltage ××
Load signal ××
Fuel level sensor ×××
ICC steering switch ×××
ASCD steering switch ×××
ICC brake switch ×××
ASCD brake switch ×××
Snow mode switch ××

EC-136
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
*: This function is not necessary in the usual service procedure.
SELF-DIAG RESULTS MODE
Self Diagnostic Item
Regarding items of DTC and 1st trip DTC, refer to EC-15, "INDEX FOR DTC" .
Freeze Frame Data and 1st Trip Freeze Frame Data
*: The items are the same as those of 1st trip freeze frame data. TARGET IDLE RPM ADJ*

IDLE CONDITION When setting target idle speed
TARGET IGN TIM ADJ*

IDLE CONDITION When adjusting target ignition tim- ing
WORK ITEM CONDITION USAGE
Freeze frame data
item* Description
DIAG TROUBLE
CODE
[PXXXX]

The engine control component part/control system has a trouble code, it is displayed as “PXXXX”. (Refer
to EC-15, "
INDEX FOR DTC" .)
FUEL SYS-B1

“Fuel injection system status” at the moment a malfunction is detected is displayed.

One mode in the following is displayed.
“Mode2”: Open loop due to detected system malfunction
“Mode3”: Open loop due to driving conditions (power enrichment, deceleration enleanment)
“Mode4”: Closed loop - using oxygen sensor(s) as feedback for fuel control
“Mode5”: Open loop - has not yet satisfied condition to go to closed loop
FUEL SYS-B2
CAL/LD VALUE [%]

The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP [ °C]
or [ °F]

The engine coolant temperature at the moment a malfunction is detected is displayed.
L-FUEL TRM-B1 [%]

“Long-term fuel trim” at the moment a malfunction is detected is displayed.

The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule
than short-term fuel trim.
L-FUEL TRM-B2 [%]
S-FUEL TRM-B1 [%]

“Short-term fuel trim” at the moment a malfunction is detected is displayed.

The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel
schedule.
S-FUEL TRM-B2 [%]
ENGINE SPEED
[rpm]

The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED [km/
h] or [mph]

The vehicle speed at the moment a malfunction is detected is displayed.
B/FUEL SCHDL
[msec]

The base fuel schedule at the moment a malfunction is detected is displayed.
INT/A TEMP SE [ °C]
or [ °F]

The intake air temperature at the moment a malfunction is detected is displayed.

TROUBLE DIAGNOSIS EC-137
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Revision: 2005 July 2005 FX
DATA MONITOR MODE
Monitored Item
× : Applicable
Monitored item [Unit] ECM
INPUT
SIG-
NALS MAIN
SIG-
NALS Description Remarks
ENG SPEED [rpm] ××

Indicates the engine speed computed from
the signal of the crankshaft position sensor
(POS) and camshaft position sensor
(PHASE).
Accuracy becomes poor if engine
speed drops below the idle rpm.

If the signal is interrupted while the
engine is running, an abnormal
value may be indicated.
MAS A/F SE-B1 [V] ××

The signal voltage of the mass air flow sensor
is displayed.
When the engine is stopped, a cer-
tain value is indicated.
B/FUEL SCHDL
[msec] ×

Base fuel schedule indicates the fuel injection
pulse width programmed into ECM, prior to
any learned on board correction.
A/F ALPHA-B1 [%] ×

The mean value of the air-fuel ratio feedback
correction factor per cycle is indicated.

When the engine is stopped, a cer-
tain value is indicated.

This data also includes the data for
the air-fuel ratio learning control.
A/F ALPHA-B2 [%]
×
COOLAN TEMP/S
[ ° C] or [ °F] ××

The engine coolant temperature (determined
by the signal voltage of the engine coolant
temperature sensor) is displayed.

When the engine coolant tempera-
ture sensor is open or short-cir-
cuited, ECM enters fail-safe mode.
The engine coolant temperature
determined by the ECM is displayed.
A/F SEN1 (B1) [V] ××

The A/F signal computed from the input signal
of the Air fuel ratio (A/F) sensor 1 is displayed.
A/F SEN1 (B2) [V] ×
HO2S2 (B1) [V] ×

The signal voltage of the heated oxygen sen-
sor 2 is displayed.
HO2S2 (B2) [V] ×
HO2S2 MNTR (B1)
[RICH/LEAN] ×

Display of heated oxygen sensor 2 signal:
RICH: means the amount of oxygen after
three way catalyst is relatively small.
LEAN: means the amount of oxygen after
three way catalyst is relatively large.

When the engine is stopped, a cer-
tain value is indicated.
HO2S2 MNTR (B2)
[RICH/LEAN] ×
VHCL SPEED SE
[km/h] or [mph] ××

The vehicle speed computed from the vehicle
speed signal sent from combination meter is
displayed.
BATTERY VOLT
[V] ××

The power supply voltage of ECM is dis-
played.
ACCEL SEN 1 [V] ××

The accelerator pedal position sensor signal
voltage is displayed.
ACCEL SEN2 signal is converted by
ECM internally. Thus, it differs from
ECM terminal voltage signal.
ACCEL SEN 2 [V]
×
THRTL SEN 1 [V] ××

The throttle position sensor signal voltage is
displayed.
THRTL SEN2 signal is converted by
ECM internally. Thus, it differs from
ECM terminal voltage signal.
THRTL SEN 2 [V]
×
FUEL T/TEMP SE
[ ° C] or [ °F] ×

The fuel temperature (determined by the sig-
nal voltage of the fuel tank temperature sen-
sor) is displayed.
INT/A TEMP SE
[ ° C] or [ °F] ××

The intake air temperature (determined by the
signal voltage of the intake air temperature
sensor) is indicated.
EVAP SYS PRES
[V] ×

The signal voltage of EVAP control system
pressure sensor is displayed.

TROUBLE DIAGNOSIS EC-141
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Revision: 2005 July 2005 FX
DATA MONITOR (SPEC) MODE
Monitored Item
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
Monitored item [Unit] ECM
input
signals Main
signals Description Remarks
ENG SPEED [rpm] ××

Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS) and camshaft position
sensor (PHASE).
MAS A/F SE-B1 [V] ××

The signal voltage of the mass air flow
sensor specification is displayed.
When engine is running specification
range is indicated.
B/FUEL SCHDL
[msec] ×

Base fuel schedule indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.

When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]
A/F ALPHA-B2 [%] ×

The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.
When engine is running specification
range is indicated.

This data also includes the data for the
air-fuel ratio learning control.
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION

Engine: Return to the original
trouble condition

Change the amount of fuel injec-
tion using CONSULT-II. If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Fuel injector

Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING

Engine: Return to the original
trouble condition

Timing light: Set

Retard the ignition timing using
CONSULT-II. If trouble symptom disappears, see
CHECK ITEM.

Perform Idle Air Volume Learning.
POWER BAL-
ANCE

Engine: After warming up, idle
the engine.

A/C switch: OFF

Shift lever: P or N

Cut off each injector signal one at
a time using CONSULT-II. Engine runs rough or dies.

Harness and connectors

Compression

Fuel injector

Power transistor

Spark plug

Ignition coil
COOLING FAN*

Ignition switch: ON

Turn the cooling fan HI, MID,
LOW and OFF using CONSULT-
II. Cooling fan moves and stops.

Harness and connectors

Cooling fan motor

IPDM E/R
ENG COOLANT
TEMP

Engine: Return to the original
trouble condition

Change the engine coolant tem-
perature using CONSULT-II. If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Engine coolant temperature sen-
sor

Fuel injector
FUEL PUMP
RELAY

Ignition switch: ON (Engine
stopped)

Turn the fuel pump relay ON and
OFF using CONSULT-II and lis-
ten to operating sound. Fuel pump relay makes the operat-
ing sound.
Harness and connectors

Fuel pump relay