2001 NISSAN ALMERA power steering

3 DETECT MALFUNCTIONING PART
Check the following.
+15A fuse
+Harness connectors E75, F36 (If so equipped)
+Harness for open or short between fuse and ECM relay
+ECM relay
+Harness for open or short between IACV-AAC and ECM relay.
©Repair harness or connectors, or replace fuse or ECM relay.
4 CHECK OUTPUT SIGNAL CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between
ECM terminal 6 and IACV-AAC valve terminal 1,
ECM terminal 7 and IACV-AAC valve terminal 4,
ECM terminal 15 and IACV-AAC valve terminal 3,
ECM terminal 16 and IACV-AAC valve terminal 6.
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 AIR CONTROL VALVE (POWER STEERING) OPERATION-I
1. Reconnect the ECM harness connector and IACV-AAC valve harness connector.
2. Disconnect the vacuum hose connected to the air control valve (Power steering) at the intake air duct.
3. Start engine and let it idle.
4. Check vacuum hose for vacuum existence.
SEF162Z
Vacuum does not exist or slightly exist.
OK or NG
OK©GO TO 6.
NG©Replace air control valve (Power steering).
IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Diagnostic Procedure (Cont'd)
EC-516

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

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

JEF137Y
Component DescriptionNJEC0451The power steering oil pressure switch is attached to the power
steering high-pressure tube and detects a power steering load.
When a power steering load is detected, it signals the ECM. The
ECM adjusts the IACV-AAC valve to increase the idle speed and
adjust for the increased load.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0452Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
PW/ST SIGNAL+Engine: After warming up, idle
the engineSteering wheel in neutral position
(forward direction)OFF
The steering wheel is fully turned ON
ECM Terminals and Reference ValueNJEC0453Specification 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)
46 PU/WPower steering oil pressure
switch[Engine is running]
+Steering wheel is fully turnedApproximately 0V
[Engine is running]
+Steering wheel is not turnedApproximately 5V
POWER STEERING OIL PRESSURE SWITCHQG
Component Description
EC-567

Wiring DiagramNJEC0450
HEC814
POWER STEERING OIL PRESSURE SWITCHQG
Wiring Diagram
EC-568

Diagnostic Procedure=NJEC0454
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. Start engine.
2. Check ªPW/ST SIGNALº in ªDATA MONITORº mode with CONSULT-II under the following conditions.
SEF311Y
OK or NG
OK©INSPECTION END
NG©GO TO 4.
3 CHECK OVERALL FUNCTION
Without CONSULT-II
1. Start engine.
2. Check voltage between ECM terminal 46 and ground under the following conditions.
SEF614Y
OK or NG
OK©INSPECTION END
NG©GO TO 4.
POWER STEERING OIL PRESSURE SWITCHQG
Diagnostic Procedure
EC-569

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-570.
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-177.
©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-570

If NG, replace power steering oil pressure switch.
POWER STEERING OIL PRESSURE SWITCHQG
Component Inspection (Cont'd)
EC-571