EC-736
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REFRIGERANT PRESSURE SENSOR
4. CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Check harness continuity between refrigerant pressure sensor terminal 1 and engine ground.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.
●Harness connectors E61, F38
●Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 83 and refrigerant pressure sensor terminal 2.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7. DETECT MALFUNCTIONING PART
Check the following.
●Harness connectors E61, F38
●Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-115, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace refrigerant pressure sensor.
NG >> Repair or replace.
Removal and InstallationEBS00NL6
REFRIGERANT PRESSURE SENSOR
Refer to ATC-129, "REFRIGERANT LINES" . Continuity should exist.
Continuity should exist.
ELECTRICAL LOAD SIGNAL
EC-737
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ELECTRICAL LOAD SIGNALPFP:25350
CONSULT-II Reference Value in Data Monitor ModeEBS00NL7
Specification data are reference values.
ECM Terminals and Reference ValueEBS00NL8
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
MONITOR ITEM CONDITION SPECIFICATION
LOAD SIGNAL
●Ignition switch: ONRear window defogger switch is ON
and/or lighting switch is in 2nd.ON
Rear window defogger switch is OFF
and lighting switch is OFF.OFF
HEATER FAN SW
●Engine: After warming up, idle
the engineHeater fan is operating. ON
Heater fan is not operating OFF
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
52 R/WElectrical load signal
(Rear window defog-
ger signal)[Ignition switch “ON”]
●Rear window defogger switch is “ON”BATTERY VOLTAGE
(11 - 14V)
[Ignition switch "ON"]
●Rear window defogger switch is "OFF"Approximately 0V
53 L/YElectrical load signal
(Headlamp signal)[Ignition switch "ON"]
●Lighting switch is "2ND" positionBATTERY VOLTAGE
(11 - 14V)
[Ignition switch "ON"]
●Lighting switch is "OFF"Approximately 0V
55 LG/BHeater fan switch sig-
nal[Ignition switch "ON"]
●Heater fan control switch is "ON"Approximately 0V
[Ignition switch "ON"]
●Heater fan control switch is "OFF"Approximately 5V
EC-740
[QR25(WITHOUT EURO-OBD)]
ELECTRICAL LOAD SIGNAL
Diagnostic Procedure
EBS00NLA
1. INSPECTION START
Do you have CONSULT-II?
Ye s o r N o
Yes >> GO TO 2.
No >> GO TO 5.
2. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-I
With CONSULT-II
1. Turn ignition switch “ON”.
2. Check “LOAD SIGNAL” in “DATA MONITOR” mode with CON-
SULT-II under the following conditions.
OK or NG
OK >> GO TO 3.
NG >> GO TO 8.
3. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-II
With CONSULT-II
1. Turn ignition switch “ON”.
2. Check “LOAD SIGNAL” in “DATA MONITOR” mode with CON-
SULT-II under the following conditions.
OK or NG
OK >> GO TO 4.
NG >> GO TO 12.
4. CHECK HEATER FAN SIGNAL CIRCUIT OVERALL FUNCTION
With CONSULT-II
1. Turn ignition switch “ON”.
2. Check “LOAD SIGNAL” in “DATA MONITOR” mode with CON-
SULT-II under the following conditions.
OK or NG
OK >>INSPECTION END
NG >> GO TO 16.
Condition LOAD SIGNAL
Rear window defogger switch “ON” ON
Rear window defogger switch “OFF” OFF
PBIB0103E
Condition LOAD SIGNAL
Lighting switch “ON” at 2nd position ON
Lighting switch “OFF” OFF
PBIB0103E
Condition LOAD SIGNAL
Heater fan control switch “ON” ON
Heater fan control switch “OFF” OFF
PBIB0103E
ELECTRICAL LOAD SIGNAL
EC-741
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5.CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-I
Without CONSULT-II
1. Turn ignition switch “ON”.
2. Check voltage between ECM terminal 52 and ground under the
following conditions.
OK or NG
OK >> GO TO 6.
NG >> GO TO 8.
6.CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-II
Without CONSULT-II
1. Turn ignition switch “ON”.
2. Check voltage between ECM terminal 53 and ground under the
following conditions.
OK or NG
OK >> GO TO 7.
NG >> GO TO 12.
7.CHECK HEATER FAN CONTROL CIRCUIT OVERALL FUNCTION
Without CONSULT-II
1. Turn ignition switch “ON”.
2. Check voltage between ECM terminal 55 and ground under the
following conditions.
OK or NG
OK >>INSPECTION END
NG >> GO TO 16.
8.CHECK REAR WINDOW DEFOGGER FUNCTION
1. Start engine.
2. Turn “ON” the rear window defogger switch.
3. Check the rear windshield. Is the rear windshield heated up?
Ye s o r N o
Ye s > > G O T O 9 .
No >> Refer to GW-10, "
REAR WINDOW DEFOGGER" .
Condition Voltage
Rear window defogger switch “ON” BATTERY VOLTAGE
Rear window defogger switch “OFF” 0V
PBIB0660E
Condition Voltage
Lighting switch “ON” at 2nd position BATTERY VOLTAGE
Lighting switch “OFF” 0V
PBIB0070E
Condition Voltage
Heater fan control switch “ON” 0V
heater fan control switch “OFF” Approximately 5V
PBIB0661E
SERVICE DATA AND SPECIFICATIONS (SDS)
EC-751
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SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
Fuel PressureEBS00NLG
Idle Speed and Ignition TimingEBS00NLH
*1: Under the following conditions:
●Air conditioner switch: OFF
●Electric load: OFF (Lights, heater fan & rear window defogger)
●Steering wheel: Kept in straight-ahead position
*2: It refrigerant pressure is low, the idle speed may not be increased.
Calculated Load ValueEBS00NLI
Mass Air Flow SensorEBS00NLJ
*: Engine is warmed up to normal operating temperature and running under no-load.
Intake Air Temperature SensorEBS00NLK
Engine Coolant Temperature SensorEBS00NLL
Heated Oxygen Sensor 1 HeaterEBS00NLM
Heated Oxygen sensor 2 HeaterEBS00NLN
Crankshaft Position Sensor (POS)EBS00NLO
Refer to EC-556, "Component Inspection" .
Fuel pressure at idle kPa (bar, kg/cm2 , psi)Approximately 350 (3.5, 3.57, 51)
Target idle speed
No-load*1 (in “P” or N” position)A/T: 700±50 rpm
M/T: 700±50 rpm
Air conditioner: ONIn “P” or N” position
A/T: 700 rpm or more*
2
M/T: 750 rpm or more*2
Ignition timingIn “P” or N” position AT: 15°±5° BTDC
MT: 15°±5° BTDC
Calculated load value% (Using CONSULT-II or GST)
At idle10 - 35
At 2,500 rpm10 - 35
Supply voltageBattery voltage (11 - 14V)
Output voltage at idle1.1 - 1.5*V
Mass air flow (Using CONSULT-II or GST)1.4 - 4.0 g·m/sec at idle*
4.0 - 10.0 g·m/sec at 2,500 rpm*
Temperature °C (°F) Resistance kΩ
25 (77)1.9 - 2.1
80 (176)0.31 - 0.37
Temperature °C (°F) Resistance kΩ
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
Resistance [at 25°C (77°F)] 2.3 - 4.3Ω
Resistance [at 25°C (77°F)] 2.3 - 4.3Ω
PRECAUTIONS
EC-757
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PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EBS00NBR
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. Information necessary to service the system safely is included in the SRS and SB section of
this Service Manual.
WARNING:
●To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.
●Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.
●Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harness connec-
tors.
On Board Diagnostic (OBD) System of Engine and A/TEBS00MS3
The ECM has an on board diagnostic system. It will light up the malfunction indicator (MI) to warn the driver of
a malfunction causing emission deterioration.
CAUTION:
●Be sure to turn the ignition switch OFF and disconnect the negative battery terminal before any
repair or inspection work. The open/short circuit of related switches, sensors, solenoid valves,
etc. will cause the MI to light up.
●Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MI to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
●Certain systems and components, especially those related to OBD, may use a new style slide-
locking type harness connector. For description and how to disconnect, refer to PG-68, "
HAR-
NESS CONNECTOR" .
●Be sure to route and secure the harnesses properly after work. The interference of the harness
with a bracket, etc. may cause the MI to light up due to the short circuit.
●Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MI to light up due to the malfunction of the fuel injection system, etc.
●Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
PrecautionEBS00MS4
●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
battery terminal. 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 ignition switch OFF and then
disconnect battery ground cable.
SEF289H
ENGINE CONTROL SYSTEM
EC-765
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System ChartEBS00MSA
*1: This sensor is not used to control the engine system under normal conditions.
*2: These signals are sent to the ECM through CAN communication line.
Multiport Fuel Injection (MFI) SystemEBS00MSB
INPUT/OUTPUT SIGNAL CHART
*1: Under normal conditions, this sensor is not for engine control operation.
*2: This signal is sent to the ECM through CAN communication line. Input (Sensor) ECM Function Output (Actuator)
●Camshaft position sensor (PHASE)
●Crankshaft position sensor (POS)
●Mass air flow sensor
●Engine coolant temperature sensor
●Heated oxygen sensor 1
●Throttle position sensor
●Accelerator pedal position sensor
●Park/neutral position (PNP) switch
●Intake air temperature sensor
●Power steering pressure sensor
●Ignition switch
●Battery voltage
●Knock sensor
●Refrigerant pressure sensor
●Heated oxygen sensor 2 *1
●TCM (Transmission control module) *2
●ESP/TCS/ABS control unit *2
●Wheel sensor
●Air conditioner switch
●Electrical loadFuel injection & mixture ratio control Fuel injectors
Electronic ignition system Power transistors
Fuel pump control Fuel pump relay
On board diagnostic system MI (On the instrument panel)
Heated oxygen sensor 1 heater control Heated oxygen sensor 1 heater
Heated oxygen sensor 2 heater control Heated oxygen sensor 2 heater
EVAP canister purge flow controlEVAP canister purge volume control
solenoid valve
Air conditioning cut control Air conditioner relay
Cooling fan control Cooling fan relays
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS)
Engine speed
Piston position
Fuel injec-
tion & mix-
ture ratio
controlFuel injectors Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Heated oxygen 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
Ignition switch Start signal
Knock sensor Engine knocking condition
Battery Battery voltage
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2 *1 Density of oxygen in exhaust gas
ESP/TCS/ABS control unit *2 ESP/TCS operation command
Wheel sensor Vehicle speed
Air conditioner switch Air conditioner operation
EC-768
[QR20(WITH EURO-OBD)]
ENGINE CONTROL SYSTEM
Electronic Ignition (EI) System
EBS00MSC
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
The ignition timing is controlled by the ECM to maintain the best air-
fuel ratio for every running condition of the engine. The ignition tim-
ing data is stored in the ECM. This data forms the map shown.
The ECM receives information such as the injection pulse width and
camshaft position sensor signal. Computing this information, ignition
signals are transmitted to the power transistor.
e.g., N: 1,800 rpm, Tp: 1.50 msec
A°BTDC
During the following conditions, the ignition timing is revised 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.
Air Conditioning Cut ControlEBS00MSD
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS)
Engine speed
Piston position
Ignition
timing con-
trolPower 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
Ignition switch Start signal
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Battery Battery voltage
Wheel sensor Vehicle speed
SEF742M
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch Air conditioner “ON” signal
Air conditioner
cut controlAir conditioner relay Throttle position sensor Throttle valve opening angle
Crankshaft position sensor (POS) Engine speed
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensor Vehicle speed