Page 1241 of 2898
6 CHECK AIR CONTROL VALVE (POWER STEERING) OPERATION-II
Check the vacuum hose for vacuum existence when steering wheel is turned.
SEF162Z
Vacuum should exist.
OK or NG
OK©GO TO 9.
NG©GO TO 7.
7 CHECK VACUUM PORT
1. Stop engine.
2. Disconnect the vacuum hose connected to the air control valve (Power steering) at the vacuum port.
3. Blow air into vacuum port.
4. Check that air flows freely.
SEF924Y
OK or NG
OK©GO TO 8.
NG©Repair or clean vacuum port.
IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Diagnostic Procedure (Cont'd)
EC-517
Page 1242 of 2898

8 CHECK VACUUM HOSES AND TUBES
1. Disconnect vacuum hoses between the air control valve (Power steering) and vacuum port, air control valve (Power
steering) and air duct.
2. Check hoses and tubes for cracks, clogging, improper connection or disconnection.
SEF109L
OK or NG
OK©GO TO 9.
NG©Repair hoses or tubes.
9 CHECK IACV-AAC VALVE
Refer to ªComponent Inspectionº, EC-519.
OK or NG
OK©GO TO 11.
NG©GO TO 10.
10 REPLACE IACV-AAC VALVE
1. Replace IACV-AAC valve assembly.
2. Perform ªIdle Air Volume Learningº, EC-57.
Is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©INSPECTION END
INCMP©Follow the construction of ªIdle Air Volume Learningº.
11 CHECK TARGET IDLE SPEED
1. Turn ignition switch ªOFFº.
2. Reconnect all harness connectors and vacuum hose.
3. Start engine and warm it up to normal operating temperature.
4. Also warm up transmission to normal operating temperature.
+For A/T models with CONSULT-II, drive vehicle until ªFLUID TEMP SEº in ªDATA MONITORº mode of ªA/Tº system indi-
cates less than 0.9V.
+For A/T models without CONSULT-II and M/T models, drive vehicle for 10 minutes.
5. Stop vehicle with engine running.
6. Check target idle speed.
M/T: 700±50 rpm
A/T: 800±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 12.
NG©Perform ªIdle Air Volume Learningº, EC-57.
IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Diagnostic Procedure (Cont'd)
EC-518
Page 1243 of 2898
12 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
©INSPECTION END
SEF605Y
SEF089X
Component InspectionNJEC1763IACV-AAC VALVENJEC1763S011) 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.
IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Diagnostic Procedure (Cont'd)
EC-519
Page 1244 of 2898

SEF505V
Component DescriptionNJEC1764A closed throttle position switch and wide open throttle position
switch are built into the throttle position sensor unit. The wide open
throttle position switch is used only for A/T control.
When the throttle valve is in the closed position, the closed throttle
position switch sends a voltage signal to the ECM. The ECM only
uses this signal to open or close the EVAP canister purge control
valve when the throttle position sensor is malfunctioning.
ECM Terminals and Reference ValueNJEC1765Specification 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 grond other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
43 Y/PUThrottle position switch
(Closed position)[Ignition switch ªONº]
+Accelerator pedal fully releasedBATTERY VOLTAGE
(11 - 14V)
[Ignition switch ªONº]
+Accelerator pedal depressedApproximately 0V
CLOSED THROTTLE POSITION SWITCH (WHERE FITTED)QG
Component Description
EC-520
Page 1245 of 2898
Wiring DiagramNJEC1766
HEC950
CLOSED THROTTLE POSITION SWITCH (WHERE FITTED)QG
Wiring Diagram
EC-521
Page 1246 of 2898
Diagnostic ProcedureNJEC1767
1 INSPECTION START
Do you have CONSULT-II?
YesorNo
Ye s©GO TO 2.
No©GO TO 3.
2 CHECK OVERALL FUNCTION
With CONSULT-II
1. Turn ignition switch ªONº.
2. Select ªA/Tº and then select ªDATA MONITORº mode with CONSULT-II.
3. Check indication of ªCLSD THL/P SWº under the following conditions. Measurement must be made with throttle position
switch installed in vehicle.
MTBL0355
OK or NG
OK©GO TO 10.
NG©GO TO 4.
3 CHECK OVERALL FUNCTION
Without CONSULT-II
1. Turn ignition switch ªONº.
2. Check voltage between ECM terminal 40 (closed throttle position switch signal) and ground under the following condi-
tions.
SEC583C
OK or NG
OK©GO TO 11.
NG©GO TO 4.
CLOSED THROTTLE POSITION SWITCH (WHERE FITTED)QG
Diagnostic Procedure
EC-522
Page 1247 of 2898
4 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect throttle position switch harness connector.
JEF091Y
3. Turn ignition switch ªONº.
4. Check voltage between terminal 5 and engine ground with CONSULT-II or tester.
SEF250W
Voltage: Battery voltage
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E74, F35
+Harness for open or short between throttle position switch and fuse block.
+10A fuse
©Repair harness or connectors.
6 CHECK INPUT SIGNAL CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 40 and throttle position switch harness connector terminal 4.
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 8.
NG©GO TO 7.
CLOSED THROTTLE POSITION SWITCH (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-523
Page 1248 of 2898

7 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.
8 ADJUST THROTTLE POSITION SWITCH IDLE POSITION
Perform Basic Inspection, EC-100.
©GO TO 9.
9 CHECK CLOSED THROTTLE POSITION SWITCH
Refer to ªComponent Inspectionº, EC-525.
OK or NG
OK (With CONSULT-II)©GO TO 10.
OK (Without CONSULT-
II)©GO TO 11.
NG©Replace throttle position switch.
10 CHECK THROTTLE POSITION SENSOR
With CONSULT-II
1. Select ªENGINEº and then select ªDATA MONITORº mode with CONSULT-II.
2. Check voltage of ªTHRTL POS SENº under the following conditins.
Voltage measurement must be made with throttle position sensor installed in vehicle.
MTBL0230
OK or NG
OK©GO TO 12.
NG©Replace throttle position sensor.
11 CHECK THROTTLE POSITION SENSOR
Without CONSULT-II
Check voltage between ECM terminal 92 (Throttle position sensor signal) and ground.
Voltage measurement must be made with throttle position sensor installed in vehicle.
YEC049A
OK or NG
OK©GO TO 12.
NG©Replace throttle position sensor.
CLOSED THROTTLE POSITION SWITCH (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-524