2001 NISSAN ALMERA TINO air condition

DescriptionNLEC1836SYSTEM DESCRIPTIONNLEC1836S01
Sensor Input Signal to ECMECM func-
tionActuator
Camshaft position sensor Engine speed
Idle air
controlIACV-AAC valve Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Throttle position sensor Throttle position
Park/neutral position (PNP) switch Park/neutral position
Air conditioner switch Air conditioner operation
Power steering oil pressure switch Power steering load signal
Battery Battery voltage
Vehicle speed sensor Vehicle speed
Intake air temperature sensor Intake air temperature
Cooling fan Cooling fan operation
Electrical load Electrical load signal
This system automatically controls engine idle speed to a specified
level. Idle speed is controlled through fine adjustment of the
amount of air which by-passes the throttle valve via IACV-AAC
valve. The IACV-AAC valve changes the opening of the air by-pass
passage to control the amount of auxiliary air. This valve is actu-
ated by a step motor built into the valve, which moves the valve in
the axial direction in steps corresponding to the ECM output sig-
nals. One step of IACV-AAC valve movement causes the respec-
tive opening of the air by-pass passage. (i.e. when the step
advances, the opening is enlarged.) The opening of the valve is
varied to allow for optimum control of the engine idling speed. The
camshaft position sensor detects the actual engine speed and
sends a signal to the ECM. The ECM then controls the step posi-
tion of the IACV-AAC valve so that engine speed coincides with the
target value memorized in ECM. The target engine speed is the
lowest speed at which the engine can operate steadily. The opti-
mum value stored in the ECM is determined by takig into consid-
eration various engine conditions, such as during warm up,
deceleration, and engine load (air conditioner, power steering and
cooling fan operation).
SEF937W
COMPONENT DESCRIPTIONNLEC1836S02IACV-AAC ValveNLEC1836S0201The IACV-AAC valve is operated by a step motor for centralized
control of auxiliary air supply. This motor has four winding phases
and is actuated by the output signals of ECM which turns ON and
OFF two windings each in seqeunce. Each time the IACV-AAC
valve opens or closes to change tha auxiliary air quantity, the ECM
sends a pulse signal to the step motor. When no change in the
auxiliary air quantity is needed, the ECM does not issue the pulse
signal. A certain voltage signal is issued so that the valve remains
at that particular opening.
IDLE AIR CONTROL VALVE (IACV) Ð
AUXILIARY AIR CONTROL (AAC) VALVE
SR20DE
Description
EC-995

CONSULT-II Reference Value in Data Monitor
Mode
NLEC1837
MONITOR ITEM CONDITION SPECIFICATION
IACV-AAC/V+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 5 - 20 steps
2,000 rpm Ð
ECM Terminals and Reference ValueNLEC1838Specification 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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
6
7
15
16BR
LG
GY/L
ORIACV-AAC valve[Engine is running]
+Warm-up condition
+Idle speed0.1 - 14V
IDLE AIR CONTROL VALVE (IACV) Ð
AUXILIARY AIR CONTROL (AAC) VALVE
SR20DE
CONSULT-II Reference Value in Data Monitor Mode
EC-996

12 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
©INSPECTION END
SEF605Y
SEF089X
Component InspectionNLEC1843IACV-AAC VALVENLEC1843S011) Disconnect IACV-AAC valve harness connector.
2) Check IACV-AAC valve resistance.
Condition Resistance
Terminal 2 and terminals 1, 3
20-24W[at 20ÉC (68ÉF)]
Terminal 5 and terminals 4, 6
3) Reconnect IACV-AAC valve harness connector.
4) Remove idle air adjusting unit assembly (IACV-AAC valve is
built-in) from throttle body.
(The IACV-AAC valve harness connector should remain con-
nected.)
5) Turn ignition switch ªONº and ªOFFº, and ensure the IACV-
AAC valve shaft smoothly moves forward and backward,
according to the ignition switch position.
If NG, replace the IACV-AAC valve.
IDLE AIR CONTROL VALVE (IACV) Ð
AUXILIARY AIR CONTROL (AAC) VALVE
SR20DE
Diagnostic Procedure (Cont'd)
EC-1003

SEF211X
Component DescriptionNLEC1924IGNITION COIL & POWER TRANSISTOR (BUILT INTO
DISTRIBUTOR)
NLEC1924S01The ignition coil is built into distributor. The ignition signal from the
ECM is sent to the power transistor. The power transistor switches
on and off the ignition coil primary circuit. As the primary circuit is
turned on and off, the proper high voltage is induced in the coil
secondary circuit.
The distributor is not repairable and must be replaced as an
assembly except distributor cap and rotor head.
CONSULT-II Reference Value in Data Monitor
Mode
NLEC1925
MONITOR ITEM CONDITION SPECIFICATION
IGN TIMING+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 15ɱ2É BTDC
2,000 rpm More than 25É BTDC
ECM Terminals and Reference ValueNLEC1926Specification 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 damage 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)
35 W/B Ignition signal[Engine is running]
+Warm-up condition
+Idle speedApproximately 0.3V
SEF996V
[Engine is running]
+Engine speed is 2,000 rpmApproximately 0.8V
SEF997V
IGNITION SIGNALSR20DE
Component Description
EC-1004

SEF138X
Component DescriptionNLEC1855The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the injector circuit, the coil in the injector is
energized. The energized coil pulls the needle valve back and
allows fuel to flow through the injector into the intake manifold. The
amount of fuel injected depends upon the injection pulse duration.
Pulse duration is the length of time the injector remains open. The
ECM controls the injection pulse duration based on engine fuel
needs.
CONSULT-II Reference Value in Data Monitor
Mode
NLEC1856
MONITOR ITEM CONDITION SPECIFICATION
INJ PULSE-B1+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 2.4 - 3.2 msec
2,000 rpm 1.9 - 2.8 msec
B/FUEL SCHDL+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 2.4 - 3.2 msec
2,000 rpm 1.4 - 2.8 msec
ECM Terminals and Reference ValueNLEC1857Specification 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)
101
103
105
107R/B
Y/B
G/B
L/BInjector No. 1
Injector No. 2
Injector No. 3
Injector No. 4[Engine is running]
+Warm-up condition
+Idle speedBATTERY VOLTAGE
(11 - 14V)
SEF011W
[Engine is running]
+Warm-up condition
+Engine speed is 2,000 rpmBATTERY VOLTAGE
(11 - 14V)
SEF012W
INJECTORSR20DE
Component Description
EC-1021

7 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors B2, M15 (LHD models), B47, M65 (RHD models)
+Harness connectors M49, F43 (where fitted)
+Harness connectors M71, F45 (where fitted)
+Harness for open or short between ECM and fuel pump relay
NG©Repair open circuit or short to ground or short to power in harness or connectors.
8 CHECK FUEL PUMP RELAY
Refer to ªComponent Inspectionº, EC-1038.
OK or NG
OK©GO TO 9.
NG©Replace fuel pump relay.
9 CHECK FUEL PUMP
Refer to ªComponent Inspectionº, EC-1038.
OK or NG
OK©GO TO 10.
NG©Replace fuel pump.
10 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
©INSPECTION END
SEF145X
Component InspectionNLEC1871FUEL PUMP RELAYNLEC1871S01Check continuity between terminals 3 and 5.
Conditions Continuity
12V direct current supply between terminals 1 and 2 Yes
No current supply No
If NG, replace relay.
SEF634Z
FUEL PUMPNLEC1871S021. Disconnect fuel level sensor unit and fuel pump harness con-
nector.
2. Check resistance between terminals 3 and 5.
Resistance: 0.2 - 5.0W[at 25ÉC (77ÉF)]
If NG, replace fuel pump.
FUEL PUMPSR20DE
Diagnostic Procedure (Cont'd)
EC-1038

JEF147Y
DescriptionNLEC1878The 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 ValueNLEC1879Specification 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 SENSORSR20DE
Description
EC-1044

10 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 12.
NG©GO TO 11.
11 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M49, F43 (where fitted)
+Harness connectors M71, F45 (where fitted)
+Harness connectors M10, E105
+Diode 1
+Harness for open and short between ECM and lighting switch connector
+Harness for open and short between ECM and headlamp relay LH
©Repair open circuit or short to ground or short to power in harness or connectors.
12 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
©INSPECTION END
ELECTRICAL LOAD SIGNALSR20DE
Diagnostic Procedure Ð Load Signal Ð (Cont'd)
EC-1058