2001 NISSAN ALMERA N16 Air condition

4 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect power steering oil pressure switch harness connector.
3. Check harness continuity between power steering oil pressure switch harness terminal 2 and engine ground.
Refer to wiring diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 5.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
5 CHECK INPUT SIGNAL CIRCUIT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 46 and power steering oil pressure switch harness terminal 1.
Refer to wiring diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 7.
NG©GO TO 6.
6 DETECT MALFUNCTIONING PART
Check the harness for open or short between ECM and power steering oil pressure switch.
©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK POWER STEERING OIL PRESSURE SWITCH
Refer to ªComponent Inspectionº, EC-473.
OK or NG
OK©GO TO 8.
NG©Replace power steering oil pressure switch.
8 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-144.
©INSPECTION END
Component InspectionNJEC0455POWER STEERING OIL PRESSURE SWITCHNJEC0455S011. Disconnect power steering oil pressure switch harness con-
nector then start engine.
2. Check continuity between terminals 1 and 2.
Refer to wiring diagram.
Conditions Continuity
Steering wheel is being fully turned. Yes
Steering wheel is not being turned. No
POWER STEERING OIL PRESSURE SWITCHQG
Diagnostic Procedure (Cont'd)
EC-473

JEF147Y
DescriptionNJEC0580The refrigerant pressure sensor is installed at the liquid tank of the
air conditioner system. The sensor uses an electrostatic volume
pressure transducer to convert refrigerant pressure to voltage. The
voltage signal is sent to ECM, and ECM controls cooling fan sys-
tem.
SEF099X
ECM Terminals and Reference ValueNJEC0581Specification 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.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
58 B Sensor's ground[Engine is running]
+Warm-up condition
+Idle speedApproximately 0V
74 R/LRefrigerant pressure
sensor[Engine is running]
+Warm-up condition
+Both A/C switch and blower switch are ªONº
(Compressor operates.)1.0 - 4.0V
111 R Sensor's power supply[Ignition switch ªONº]Approximately 5V
REFRIGERANT PRESSURE SENSORQG
Description
EC-475

11 CHECK HEADLAMP INPUT SIGNAL CIRCUIT
Without Daytime Light system
1. Stop engine.
2. Disconnect ECM harness connector.
3. Disconnect lighting switch connector.
4. Check harness continuity between ECM terminal 50 and lighting switch connector terminal 10 under the following con-
ditions.
SEF161Z
5. Also check harness for short to ground and short to power.
With Daytime Light system
1. Stop engine.
2. Disconnect ECM harness connector.
3. Disconnect headlamp relay LH connector.
4. Check harness continuity between ECM terminal 50 and headlamp relay LH connector terminal 3 under the following
conditions.
SEF445Z
5. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 13.
NG©GO TO 12.
12 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M63, F102
+Harness connectors M159, F174
+Diode E177
+Harness for open and short between ECM and lighting switch connector
©Repair open circuit or short to ground or short to power in harness or connectors.
13 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-144.
©INSPECTION END
ELECTRICAL LOAD SIGNALQG
Diagnostic Procedure Ð Load Signal Ð (Cont'd)
EC-486

Diagnostic Procedure Ð Heater Control Panel
(Fan Switch) Ð
NJEC0585
1 CHECK CIRCUIT OVERALL FUNCTION
1. Start engine.
2. Heater fan motor switch ªONº.
3. Check voltage between ECM terminal 51 and ground under the following conditions.
SEF620Y
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK INPUT SIGNAL CIRCUIT
1. Stop engine.
2. Disconnect ECM harness connector.
3. Disconnect heater control panel fan switch harness connector.
4. Check harness continuity between ECM terminal 51 and heater fan switch harness connector terminal 18.
Refer to wiring diagram.
Continuity should exist.
5. Also check harness for short to ground and short to power.
OK or NG
OK©Refer to HA-54, ªBLOWER MOTORº.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M169, F113
+Harness for open and short between ECM and heater fan motor switch
©Repair open circuit or short to ground or short to power in harness or connectors.
ELECTRICAL LOAD SIGNALQG
Diagnostic Procedure Ð Heater Control Panel (Fan Switch) Ð
EC-487

Fuel Pressure RegulatorNJEC0467
Fuel pressure at idling
kPa (bar, kg/cm2, psi)Vacuum hose is connected Approximately 235 (2.35, 2.4, 34)
Vacuum hose is disconnected Approximately 294 (2.94, 3.0, 43)
Idle Speed and Ignition TimingNJEC0468
Target idle speed* rpmM/T: 700±50
A/T: 800±50
Air conditioner: ON rpm825 or more
Ignition timingM/T: 8±5É BTDC
A/T: 10±5É BTDC
Throttle position sensor idle position V 0.15 - 0.85
*: Under the following conditions:
+Air conditioner switch: OFF
+Electrical load: OFF (Lights, heater fan & rear window defogger)
+Steering wheel: Kept in straight-ahead position
Mass Air Flow SensorNJEC0470
Supply voltage (Heater) VBattery voltage (11 - 14)
Supply voltage (Sensor) VApproximately 5
Output voltage V1.0 - 1.7*
Mass air flow
(Using CONSULT-II or GST) g´m/sec1.0 - 4.0 at idle*
5.0 - 10.0 at 2,500 rpm*
*: Engine is warmed up to normal operating temperature and idling under no-load.
Intake Air Temperature SensorNJEC0480
Temperature ÉC (ÉF) Resistance kW
20 (68) 2.1 - 2.9
80 (176) 0.27 - 0.38
Engine Coolant Temperature SensorNJEC0471
Temperature ÉC (ÉF) Resistance kW
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
Throttle Position SensorNJEC0477
Throttle valve conditions Voltage (V)
Completely closed0.15 - 0.85
Completely open3.5 - 4.7
Heated Oxygen Sensor 1 Heater (Front)NJEC0478
Resistance [at 25ÉC (77ÉF)]W2.3 - 4.3
Heated Oxygen Sensor 2 Heater (Rear)NJEC0483
Resistance [at 25ÉC (77ÉF)]W2.3 - 4.3
SERVICE DATA AND SPECIFICATIONS (SDS)QG
Fuel Pressure Regulator
EC-489

System ChartNJEC0611
Input (Sensor) ECM Function Output (Actuator)
+Electronic control fuel injection pump
+Crankshaft position sensor (TDC)
+Engine coolant temperature sensor
+Accelerator position sensor
+Accelerator position switch
+Park/Neutral position (PNP) switch*
+Ignition switch
+Battery voltage
+Vehicle speed sensor
+Air conditioner switch
+Mass air flow sensor
+Stop lamp switchFuel injection controlElectronic control fuel injection
pump
Fuel injection timing controlElectronic control fuel injection
pump
Fuel cut controlElectronic control fuel injection
pump
Glow control system Glow relay & glow lamp
On board diagnostic system MI (On the instrument panel)
EGR volume control EGR volume control valve
Cooling fan control Cooling fan relay
Air conditioning cut control Air conditioner relay
*: If so equipped
ENGINE AND EMISSION CONTROL OVERALL SYSTEMYD
System Chart
EC-504

Fuel Injection Control System
DESCRIPTIONNJEC0612System DescriptionNJEC0612S01Three types of fuel injection control are provided to accommodate engine operating conditions; normal control,
idle control and start control. The ECM determines the appropriate fuel injection control. Under each control,
the amount of fuel injected is compensated to improve engine performance.
Pulse signals are exchanged between ECM and electronic control fuel injection pump (control unit is built-in).
The fuel injection pump control unit performs duty control on the spill valve (built into the fuel injection pump)
according to the input signals to compensate the amount of fuel injected to the preset value.
Start ControlNJEC0612S02Input/Output Signal ChartNJEC0612S0201
Sensor Input Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection
control (start
control)Electronic control fuel
injection pump Crankshaft position sensor (TDC) Engine speed
Ignition switch Start signal
SEF648S
When the ECM receives a start signal from the ignition switch, the ECM adapts the fuel injection system for
the start control. The amount of fuel injected at engine starting is a preset program value in the ECM. The
program is determined by the engine speed and engine coolant temperature.
For better startability under cool engine conditions, the lower the coolant temperature becomes, the greater
the amount of fuel injected. The ECM ends the start control when the engine speed reaches the specific value,
and shifts the control to the normal or idle control.
Idle ControlNJEC0612S03Input/Output Signal ChartNJEC0612S0301
Sensor Input Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection
control (Idle con-
trol)Electronic control fuel
injection pump Crankshaft position sensor (TDC) Engine speed
Battery Battery voltage
Accelerator position switch Idle position
Vehicle speed sensor Vehicle speed
Air conditioner switch Air conditioner signal
When the ECM determines that the engine speed is at idle, the fuel injection system is adapted for the idle
control. The ECM regulates the amount of fuel injected corresponding to changes in load applied to the engine
to keep engine speed constant. The ECM also provides the system with a fast idle control in response to the
engine coolant temperature signal.
ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTIONYD
Fuel Injection Control System
EC-505

Normal ControlNJEC0612S04Input/Output Signal ChartNJEC0612S0401
Sensor Input Signal to ECM ECM Function Actuator
Crankshaft position sensor (TDC) Engine speedFuel injection
control (Normal
control)Electronic control fuel
injection pump
Accelerator position sensor Accelerator position
SEF649S
The amount of fuel injected under normal driving conditions is determined according to sensor signals. The
crankshaft position sensor (TDC) detects engine speed and the accelerator position sensor detects accelera-
tor position. These sensors send signals to the ECM.
The fuel injection data, predetermined by correlation between various engine speeds and accelerator positions,
are stored in the ECM memory, forming a map. The ECM determines the optimal amount of fuel to be injected
using the sensor signals in comparison with the map.
Maximum Amount ControlNJEC0612S05Input/Output Signal ChartNJEC0612S0501
Sensor Input Signal to ECM ECM Function Actuator
Mass air flow sensor Amount of intake air
Fuel injection
control (Maxi-
mum amount
control)Electronic control fuel
injection pump Engine coolnat temperature sensor Engine coolant temperature
Crankshaft position sensor (TDC) Engine speed
Accelerator position sensor Accelerator position
The maximum injection amount is controlled to an optimum by the engine speed, intake air amount, engine
coolant temperature, and accelerator opening in accordance with the driving conditions.
This prevents the oversupply of the injection amount caused by decreased air density at a high altitude or
during a system failure.
Deceleration ControlNJEC0612S06Input/Output Signal ChartNJEC0612S0601
Sensor Input Signal to ECM ECM Function Actuator
Accelerator position switch Accelerator positionFuel injection
control (Decel-
eration control)Electronic control fuel
injection pump
Crankshaft position sensor (TDC) Engine speed
The ECM sends a fuel cut signal to the electronic control fuel injection pump during deceleration for better
fuel efficiency. The ECM determines the time of deceleration according to signals from the accelerator posi-
tion switch and crankshaft position sensor (TDC).
Fuel Injection Timing Control System
DESCRIPTIONNJEC0613The target fuel injection timing in accordance with the engine speed and the fuel injection amount are recorded
as a map in the ECM beforehand. The ECM and the injection pump control unit exchange signals and per-
form feedback control for optimum injection timing in accordance with the map.
ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTIONYD
Fuel Injection Control System (Cont'd)
EC-506