2001 NISSAN ALMERA N16 Air condition

DescriptionNJEC0279SYSTEM DESCRIPTIONNJEC0279S01
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed
Idle air
controlIACV-AAC valve Camshaft position sensor (PHASE) Engine speed and cylinder number
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Throttle position sensor Throttle 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
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
crankshaft position sensor (POS) detects the actual engine speed
and sends a signal to the ECM. The ECM then controls the step
position 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 taking into consid-
eration various engine conditions, such as during warm up,
deceleration, and engine load (air conditioner, power steering, cool-
ing fan operation and electrical load).
SEF937W
COMPONENT DESCRIPTIONNJEC0279S02IACV-AAC ValveNJEC0279S0202The 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 sequence. Each time the IACV-AAC
valve opens or closes to change the 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.
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Description
EC-313

CONSULT-II Reference Value in Data Monitor
Mode
NJEC0280
MONITOR ITEM CONDITION SPECIFICATION
IACV-AAC/V+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 5 - 25 steps
2,000 rpm Ð
ECM Terminals and Reference ValueNJEC0281Specification 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
P
ORIACV-AAC valve[Engine is running]
+Warm-up condition
+Idle speed0.1 - 14V
On Board Diagnosis LogicNJEC0282
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0505
0505+An improper voltage signal is sent to ECM through the
valve.+Harness or connectors
(The IACV-AAC valve circuit is open.)
+IACV-AAC valve
SEF058Y
DTC Confirmation ProcedureNJEC0283NOTE:
+If ªDTC Confirmation Procedureº has been previously
conducted, always turn ignition switch ªOFFº and wait at least
9 seconds before conducting the next test.
+If the target idle speed is out of the specified value, per-
form ªIdle Air Volume Learningº, refer to EC-55, before
conducting ªDTC Confirmation Procedureº. For the target
idle speed, refer to ªSERVICE DATA AND SPECIFICA-
TIONS (SDS)º, EC-489.
With CONSULT-II
1) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and warm it up to normal operating temperature.
4) Rev engine from idle to 2,000 rpm 20 times.
If 1st trip DTC is detected, go to ªDIAGNOSTIC
PROCEDUREº, EC-297.
With GST
Follow the procedure ªWith CONSULT-IIº above.
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
CONSULT-II Reference Value in Data Monitor Mode
EC-314

SEF605Y
SEF089X
Component InspectionNJEC0286IACV-AAC VALVENJEC0286S011) 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 engine.
(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.
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Component Inspection
EC-320

4 DETECT MALFUNCTIONING PART
Check the following.
+Harness for open or short between throttle position switch and ECM
+Harness for open or short between throttle position switch and TCM (Transmission Control Module)
©Repair open circuit or short to ground or short to power in harness or connectors.
5 ADJUST THROTTLE POSITION SWITCH IDLE POSITION
Perform Basic Inspection, EC-98.
©GO TO 6.
6 CHECK CLOSED THROTTLE POSITION SWITCH
Refer to ªComponent Inspectionº, EC-325.
OK or NG
OK©GO TO 7.
NG©Replace throttle position switch.
7 CHECK THROTTLE POSITION SENSOR
Refer to ªComponent Inspectionº, EC-174.
OK or NG
OK©GO TO 8.
NG©Replace throttle position sensor.
8 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-144.
©INSPECTION END
SEF197Y
Component InspectionNJEC0294CLOSED THROTTLE POSITION SWITCHNJEC0294S01With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Stop engine and turn ignition switch ªONº.
3) Select ªDATA MONITORº mode with CONSULT-II.
4) Check indication of ªCLSD THL/P SWº under the following
conditions.
NOTE:
Measurement must be made with closed throttle position
switch installed in vehicle.
Throttle valve conditions CLSD THL/P SW
Completely closed ON
Partially open or completely open OFF
If NG, adjust closed throttle position switch. Refer to ªBasic
Inspectionº, EC-98.
5) If it is impossible to adjust closed throttle position switch in
ªBasic Inspectionº, replace closed throttle position switch.
Without CONSULT-II
DTC P0510 CLOSED THROTTLE POSITION SWITCH (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-325

System DescriptionNJEC0433COOLING FAN CONTROLNJEC0433S01
Sensor Input Signal to ECMECM func-
tionActuator
Vehicle speed sensor Vehicle speed
Cooling fan
controlCooling fan relay(s) Engine coolant temperature sensor Engine coolant temperature
Air conditioner switch Air conditioner ªONº signal
Ignition switch Start signal
Refrigerant pressure sensor Refrigerant pressure
The ECM controls the cooling fan corresponding to the vehicle speed, engine coolant temperature, refriger-
ant pressure, and air conditioner ON signal. The control system has ON-OFF control.
OPERATIONNJEC0433S02Engine coolant temperatures at which the cooling fan turns ªONº are indicated in the Table below.
Vehicle speed km/h (MPH)
Air conditioner switchHigh pressure of
refrigerant
kPa (bar, kg/cm
2, psi)Less than 50 (30) 50 - 80 (30 - 50) More than 80 (50)
ONMore than 1,680
(16.8, 17.14, 244)Always Always More than 95ÉC (203ÉF)
Less than 1,680
(16.8, 17.14, 244)Always More than 95ÉC (203ÉF) More than 95ÉC (203ÉF)
OFFMore than 100ÉC
(212ÉF)More than 95ÉC (203ÉF) More than 95ÉC (203ÉF)
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0486Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
AIR COND SIG+Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates)ON
COOLING FAN+After warming up engine, idle
the engine.
+Air conditioner switch: OFFEngine coolant temperature is less
than 100ÉC (212ÉF)OFF
Engine coolant temperature is
100ÉC (212ÉF) or moreON
DTC P1217 OVERHEAT (COOLING SYSTEM)QG
System Description
EC-334

ECM Terminals and Reference Value=NJEC0487Specification 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)
13 LG/R Cooling fan relay[Engine is running]
+Cooling fan is not operatingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
+Cooling fan is operating0 - 0.6V
23 L/W Air conditioner switch[Engine is running]
+Both air conditioner switch and blower switch are
ªONº (Compressor operates)Approximately 0V
[Engine is running]
+Air conditioner switch is ªOFFºBATTERY VOLTAGE
(11 - 14V)
On Board Diagnosis LogicNJEC0572If the cooling fan or another component in the cooling system malfunctions, engine coolant temperature will
rise.
When the engine coolant temperature reaches an abnormally high temperature condition, a malfunction is
indicated.
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P1217
1217+The engine coolant temperature is extraordinary high,
even when the load is not heavy.+Harness or connectors
(The cooling fan circuit is open or shorted)
+Cooling fan
+Thermostat
+Improper ignition timing
+Engine coolant temperature sensor
+Blocked radiator
+Blocked front end (Improper fitting of nose mask)
+Crushed vehicle frontal area (Vehicle frontal is
collided but not repaired)
+Blocked air passage by improper installation of
front fog lamp or fog lamps.
+Improper mixture ratio of coolant
+Damaged bumper
For more information, refer to ªMAIN 12 CAUSES
OF OVERHEATINGº, EC-345.
CAUTION:
When a malfunction is indicated, be sure to replace the coolant following the procedure in the LC-17,
ªChanging Engine Coolantº. Also, replace the engine oil.
1) Fill radiator with coolant up to specified level with a filling speed of 2 liters per minute. Be sure to use
coolant with the proper mixture ratio. Refer to MA-22, ªAnti-freeze Coolant Mixture Ratioº, ªRECOM-
MENDED FLUIDS AND LUBRICANTSº.
2) After refilling coolant, run engine to ensure that no water-flow noise is emitted.
DTC P1217 OVERHEAT (COOLING SYSTEM)QG
ECM Terminals and Reference Value
EC-335

SEF621WA
SEF646X
SEC163BA
Overall Function CheckNJEC0489Use this procedure to check the overall function of the cooling fan.
During this check, a DTC might not be confirmed.
WARNING:
Never remove the radiator cap when the engine is hot. Serious
burns could be caused by high pressure fluid escaping from
the radiator.
Wrap a thick cloth around cap. Carefully remove the cap by
turning it a quarter turn to allow built-up pressure to escape.
Then turn the cap all the way off.
With CONSULT-II
1) Check the coolant level and mixture ratio (using coolant tester)
in the reservoir tank and radiator.
Allow engine to cool before checking coolant level and
mixture ratio.
+If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to ªDiagnos-
tic Procedureº, EC-339.
+If the coolant mixture ratio is out of the range of 45 to 55%,
replace the coolant in the following procedure LC-17, ªChang-
ing Engine Coolantº.
2) Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to ªDiagnos-
tic Procedureº, EC-339.
3) Turn ignition switch ªONº.
4) Perform ªCOOLING FANº in ªACTIVE TESTº mode with CON-
SULT-II.
5) If the results are NG, go to ªDiagnostic Procedureº, EC-339.
Without CONSULT-II
1) Check the coolant level and mixture ratio (using coolant tester)
in the reservoir tank and radiator.
Allow engine to cool before checking coolant level and
mixture ratio.
+If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to ªDiagnos-
tic Procedureº, EC-339.
+If the coolant mixture ratio is out of the range of 45 to 55%,
replace the coolant in the following procedure LC-17, ªChang-
ing Engine Coolantº.
2) Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to ªDiagnos-
tic Procedureº, EC-339.
3) Start engine.
Be careful not to overheat engine.
4) Set temperature control lever to full cold position.
5) Turn air conditioner switch ªONº.
6) Turn blower fan switch ªONº.
7) Run engine at idle for a few minutes with air conditioner oper-
ating.
Be careful not to overheat engine.
8) Make sure that cooling fan operates. Refer to ªOPERATIONº
table for cooling fan, EC-334.
If NG, go to ªDiagnostic Procedureº, EC-339.
DTC P1217 OVERHEAT (COOLING SYSTEM)QG
On Board Diagnosis Logic (Cont'd)
EC-336

Diagnostic ProcedureNJEC0491
1 CHECK COOLING FAN OPERATION
1. Start engine and let it idle.
2. Set temperature lever at full cold position.
3. Turn air conditioner switch ªONº.
4. Turn blower fan switch ªONº.
5. Make sure that cooling fans-1 and -2 operate.
SEC163BA
OK or NG
OK©GO TO 11.
NG©GO TO 2.
2 CHECK AIR CONDITIONER OPERATION
Is air conditioner operating?
(Check operation of compressor and blower motor.)
OK or NG
OK©GO TO 3.
NG©Check for failure of air conditioner to operate. Refer to HA section.
DTC P1217 OVERHEAT (COOLING SYSTEM)QG
Diagnostic Procedure
EC-339