2008 INFINITI FX35 battery

EC-26
< SERVICE INFORMATION >[VQ35DE]
PRECAUTIONS
Precaution
INFOID:0000000001325892
 Always use a 12 volt battery as power source.
 Do not attempt to disconnect battery cables while engine is
running.
 Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
 Before removing parts, turn ig nition switch OFF and then dis-
connect negative battery cable.
 Do not disassemble ECM.
 If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-c ontrol at its initial value.
Engine operation can vary slight ly when the terminal is dis-
connected. However, this is no t an indication of a malfunc-
tion. Do not replace parts b ecause of a slight variation.
 If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
 When connecting ECM harness co nnector, fasten it securely
with a lever as far as it will go as shown in the figure.
 When connecting or disconnect ing pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM pin
terminal, when connecting pin connectors.
 Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge) volt-
age to develop in coil and co ndenser, thus resulting in dam-
age to ICs.
 Keep engine control system harn ess at least 10 cm (4 in) away
from adjacent harness, to preven t engine control system mal-
functions due to receiving exter nal noise, degraded operation
of ICs, etc.
 Keep engine control system parts and harness dry.
SEF289H
PBIB1164E
PBIB1512E
PBIB0090E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-32
< SERVICE INFORMATION >[VQ35DE]
ENGINE CONTROL SYSTEM
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is
determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). T he amount of fuel injected is a program value in the
ECM memory. The program value is preset by engi ne operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
VARIOUS FUEL INJECTION I NCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compens ated to improve engine performance under various operat-
ing conditions as listed below.
 During warm-up
 When starting the engine
 During acceleration
 Hot-engine operation
 When selector lever is changed from N to D
 High-load, high-speed operation
 During deceleration
 During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system prov ides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst 1 can then better reduce CO, HC and NOx emissions. This system uses air fuel ratio
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Knock sensor Engine knocking condition
Battery
Battery voltage*
3
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
Air conditioner switch Air conditioner operation*
2
Wheel sensorVehicle speed*2
PBIB3020E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-34
< SERVICE INFORMATION >[VQ35DE]
ENGINE CONTROL SYSTEM
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration,
operation of the engine at excessively high speeds or oper-
ation of the vehicle at excessively high speeds.
Electronic Ignition (EI) SystemINFOID:0000000001325897
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
Firing order: 1 - 2 - 3 - 4 - 5 - 6
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition si gnals are transmitted to the power transistor.
During the following conditions, the ignition timing is re vised by the ECM according to the other data stored in
the ECM.
 At starting
 During warm-up
 At idle
 At low battery voltage
 During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Fuel Cut Control (at No Load and High Engine Speed)INFOID:0000000001325898
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
2
Piston position
Ignition timing
controlPower transistor
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
2
Wheel sensor
Vehicle speed*1
Sensor Input Signal to ECM ECM function Actuator
Park/neutral position (P NP) switch Neutral position
Fuel cut control Fuel injector
Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
Engine speed
Wheel sensor Vehicle speed*
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-36
< SERVICE INFORMATION >[VQ35DE]
AIR CONDITIONING CUT CONTROL
AIR CONDITIONING CUT CONTROL
Input/Output Signal ChartINFOID:0000000001325899
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
System DescriptionINFOID:0000000001325900
This system improves engine operati
on when the air conditioner is used.
Under the following conditions, the air conditioner is turned OFF.
 When the accelerator pedal is fully depressed.
 When cranking the engine.
 At high engine speeds.
 When the engine coolant temperature becomes excessively high.
 When operating power steering during low engine speed or low vehicle speed.
 When engine speed is excessively low.
 When refrigerant pressure is excessively low or high.
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch Air conditioner ON signal*
1
Air conditioner
cut controlAir conditio
ner relay
Accelerator pedal position sensor Accelerator pedal position
Throttle position sensor Throttle position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
Engine speed*2
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
2
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensorVehicle speed*
1
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EVAPORATIVE EMISSION SYSTEMEC-45
< SERVICE INFORMATION > [VQ35DE]
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3. Turn ignition switch ON.
4. Select the “EVAP SYSTEM CLOSE” of
“WORK SUPPORT MODE” with CONSULT-III.
5. Touch “START”. A bar graph (Pressure indicating display) will appear on the screen.
6. Apply positive pressure to the EVAP system until t he pressure indicator reaches the middle of the bar
graph.
7. Remove EVAP service port adapter and hose with pressure pump.
8. Locate the leak using a leak detector. Refer to EC-40, "
Descrip-
tion".
WITHOUT CONSULT-III
1. Attach the EVAP service port adapter securely to the EVAP ser-
vice port.
2. Also attach the pressure pump with pressure gauge to the EVAP service port adapter.
3. Apply battery voltage between the terminals of EVAP c anister vent control valve to make a closed EVAP
system.
4. To locate the leak, deliver positive pressure to the EVAP system until pressure gauge points reach 1.38 to
2.76 kPa (0.014 to 0.028 kg/cm
2, 0.2 to 0.4 psi).
5. Remove EVAP service port adapter and hose with pressure pump.
6. Locate the leak using a leak detector. Refer to EC-40, "
Description".
SEF200U
SEF462UA
PBIB1611E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-46
< SERVICE INFORMATION >[VQ35DE]
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
ON BOARD REFUELING VA
POR RECOVERY (ORVR)
System DescriptionINFOID:0000000001325908
From the beginning of refueling, the air and vapor insi de the fuel tank go through refueling EVAP vapor cut
valve and EVAP/ORVR line to the EVAP canister. The vapor is absorbed by the EVAP canister and the air is
released to the atmosphere.
When the refueling has reached the full level of the fuel tank, the refueling EVAP vapor cut valve is closed and
refueling is stopped because of auto shut-off. The vapor which was absorbed by the EVAP canister is purged
during driving.
WARNING:
When conducting inspections below, be sure to observe the following:
 Put a “CAUTION: FLAMMABLE” sign in workshop.
 Do not smoke while servicing fuel system. Keep open flames and sparks away from work area.
 Be sure to furnish the workshop with a CO
2 fire extinguisher.
CAUTION:
 Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-pr oof container and put lid on securely.
- Release fuel pressure from fuel line. Refer to EC-87, "
Fuel Pressure Check".
- Disconnect negative battery cable.
 Always replace O-ring when the fuel gauge retainer is removed.
 Do not kink or twist hose and tube when they are installed.
 Do not tighten hose and clamps excessively to avoid damaging hoses.
 After installation, run engine an d check for fuel leaks at connection.
 Do not attempt to top off the fuel tank afte r the fuel pump nozzle shuts off automatically.
Continued refueling may cause fu el overflow, resulting in fuel spray and possibly a fire.
Diagnosis ProcedureINFOID:0000000001325909
SYMPTOM: FUEL ODOR FROM EVAP CANISTER IS STRONG.
1.CHECK EVAP CANISTER
1. Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
2. Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be l ess than 2.1 kg (4.6 lb).
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
PBIB1068E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

ON BOARD DIAGNOSTIC (OBD) SYSTEMEC-71
< SERVICE INFORMATION > [VQ35DE]
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1. If the ignition switch stays ON after repair work, be su
re to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.
2. Perform AT-38, "
OBD-II Diagnostic Trouble Code (DTC)". (The DTC in TCM will be erased.)
3. Select Service $04 with GST (Generic Scan Tool).
No Tools
NOTE:
If the DTC is not for A/T related items (see EC-17
), skip step 2.
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once.
Wait at least 10 seconds and then turn it ON (engine stopped) again.
2. Perform AT-38, "
OBD-II Diagnostic Trouble Code (DTC)". (The DTC in TCM will be erased.)
3. Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal. Refer to
EC-71, "
Malfunction Indicator Lamp (MIL)".
 If the battery is disconnected, the emission-relate d diagnostic information will be lost within 24
hours.
 The following data are cleared when the ECM memory is erased.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
Actual work procedures are explained using a DTC as an ex ample. Be careful so that not only the DTC, but all
of the data listed above, are cleared from the ECM memory during work procedures.
Malfunction Indicator Lamp (MIL)INFOID:0000000001325917
DESCRIPTION
The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned ON with-
out the engine running. This is a bulb check.
If the MIL does not light up, refer to DI-34
or see EC-591.
2. When the engine is start ed, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.
ON BOARD DIAGNOSTIC SYSTEM FUNCTION
The on board diagnostic system has the following three functions.
SEF217U
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-74
< SERVICE INFORMATION >[VQ35DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
tified codes can be identified by using the CONSULT-II
I or GST. A DTC will be used as an example for how to
read a code.
A particular trouble code can be identified by the number of four-digit numeral flashes. The “zero” is indicated
by the number of ten flashes. The “A” is indicated by the number of eleven flash. The length of time the
1,000th-digit numeral flashes on and off is 1.2 seconds consisting of an ON (0.6-second) - OFF (0.6-second)
cycle.
The 100th-digit numeral and lower digit numerals cons ist of a 0.3-second ON and 0.3-second OFF cycle.
A change from one digit numeral to another occurs at an inte rval of 1.0-second OFF. In other words, the later
numeral appears on the display 1.3 seconds after the former numeral has disappeared.
A change from one trouble code to another occu rs at an interval of 1.8-second OFF.
In this way, all the detected malfunctions are classi fied by their DTC numbers. The DTC 0000 refers to no mal-
function. (See EC-17
)
How to Erase Diagnostic Test Mode II (Self-diagnostic Results)
The DTC can be erased from the back up memory in t he ECM by depressing accelerator pedal. Refer to "How
to Set Diagnostic Test Mode II (Self-diagnostic Results)".
 If the battery is disconnected, the DTC will be lost from the backup memory within 24 hours.
 Be careful not to erase the stored memo ry before starting trouble diagnoses.
OBD System Operation ChartINFOID:0000000001325918
RELATIONSHIP BETWEEN MIL, 1ST TRIP DTC, DTC, AND DETECTABLE ITEMS
 When a malfunction is detected for the 1st time, the 1st trip DTC and the 1st trip freeze frame data are
stored in the ECM memory.
 When the same malfunction is detected in two consec utive trips, the DTC and the freeze frame data are
stored in the ECM memory, and the MIL will come on. For details, refer to EC-54, "
Two Trip Detection Logic".
 The MIL will go off after the vehicle is driven 3 time s (drive pattern B) with no malfunction. The drive is
counted only when the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs
while counting, the counter will reset.
 The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (driving pattern A) with-
out the same malfunction recurring (except for Misfire and Fuel Injection System). For Misfire and Fuel Injec-
tion System, the DTC and freez e frame data will be stored until the vehicle is driven 80 times (driving pattern
PBIB3005E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C