2003 NISSAN TEANA power steering

TROUBLE DIAGNOSIS
EC-81
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ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
X: Applicable
*1: This item includes 1st trip DTCs.
*2: This mode includes 1st trip freeze frame data or freeze frame data. The items appear on CONSULT-II screen in freeze frame data
mode only if a 1st trip DTC or DTC is detected. For details, refer to EC-35
. ItemDIAGNOSTIC TEST MODE
WORK
SUPPORTSELF-DIAGNOSTIC
RESULTS
DATA
MONI-
TORDATA
MONITOR
(SPEC)ACTIVE
TEST DTC*
1FREEZE
FRAME
DATA*
2
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS)××××
Camshaft position sensor (PHASE)×××
Mass air flow sensor×××
Engine coolant temperature sensor×××××
Heated oxygen sensor 1×××
Heated oxygen sensor 2××
Vehicle speed signal××××
Accelerator pedal position sensor×××
Throttle position sensor×××
Intake air temperature sensor×× ×
Knock sensor×
Refrigerant pressure sensor××
Closed throttle position switch (accelerator
pedal position sensor signal)××
Air conditioner switch××
Park/neutral position (PNP) switch×××
Stop lamp switch×××
Power steering pressure sensor×××
Battery voltage××
Electrical load signal××
ENGINE CONTROL COMPONENT PARTS
OUTPUT
Fuel injector×××
Power transistor (Ignition timing)×××
Throttle control motor relay×××
Throttle control motor×
EVAP canister purge volume control sole-
noid valve×××
Air conditioner relay××
Fuel pump relay××××
Cooling fan relay××××
Heated oxygen sensor 1 heater××
Heated oxygen sensor 2 heater××
Intake valve timing control solenoid valve××××

EC-84
[QR]
TROUBLE DIAGNOSIS

INT/A TEMP SE
[°C] or [°F]××
The intake air temperature (determined by
the signal voltage of the intake air tempera-
ture sensor) is indicated.
START SIGNAL
[ON/OFF]××

Indicates start signal status [ON/OFF] com-
puted by the ECM according to the signals
of engine speed and battery voltage.
After starting the engine, [OFF] is dis-
played regardless of the starter sig-
nal.
CLSD THL POS
[ON/OFF]××

Indicates idle position [ON/OFF] computed
by ECM according to the accelerator pedal
position sensor signal.
AIR COND SIG
[ON/OFF]××

Indicates [ON/OFF] condition of the air con-
ditioner switch as determined by the air
conditioner signal.
P/N POSI SW
[ON/OFF]××

Indicates [ON/OFF] condition from the park/
neutral position (PNP) switch signal.
PW/ST SIGNAL
[ON/OFF]××

[ON/OFF] condition of the power steering
system (determined by the power steering
pressure sensor signal) is indicated.
LOAD SIGNAL
[ON/OFF]××

Indicates [ON/OFF] condition from the elec-
trical load signal.
ON: Rear window defogger switch is ON
and/or lighting switch is in 2nd position.
OFF: Both rear window defogger switch
and lighting switch are OFF.
IGNITION SW
[ON/OFF]×

Indicates [ON/OFF] condition from ignition
switch.
HEATER FAN SW
[ON/OFF]×

Indicates [ON/OFF] condition from the
heater fan switch signal.
BRAKE SW
[ON/OFF]×

Indicates [ON/OFF] condition from the stop
lamp switch signal.
INJ PULSE-B1
[msec]×

Indicates the actual fuel injection pulse
width compensated by ECM according to
the input signals.
When the engine is stopped, a cer-
tain computed value is indicated.
IGN TIMING [BTDC]×

Indicates the ignition timing computed by
ECM according to the input signals.
When the engine is stopped, a cer-
tain value is indicated.
PURG VOL C/V [%]

Indicates the EVAP canister purge volume
control solenoid valve control value com-
puted by the ECM according to the input
signals.

The opening becomes larger as the value
increases.
INT/V TIM (B1) [°CA]

Indicates [°CA] of intake camshaft
advanced angle.
INT/V SOL (B1) [%]

The control value of the intake valve timing
control solenoid valve (determined by ECM
according to the input signal) is indicated.

The advance angle becomes larger as the
value increases
AIR COND RLY
[ON/OFF]×

The air conditioner relay control condition
(determined by ECM according to the input
signals) is indicated. Monitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-101
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15. DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect ECM harness connector. Check pin terminal and connector for damage, and then reconnect it.
>> GO TO 16.
16. CHECK “A/F ALPHA-B1”
1. Start engine.
2. Select “A/F ALPHA-B1” in “DATA MONITOR (SPEC)” mode, and make sure that the each indication is
within the SP value.
OK or NG
OK >>INSPECTION END
NG >> Detect malfunctioning part according to EC-60, "
Symptom Matrix Chart" .
17. CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and
make sure that the indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG (More than the SP value)>>GO TO 18.
NG (Less than the SP value)>>GO TO 25.
18. DETECT MALFUNCTIONING PART
1. Check for the cause of large engine friction. Refer to the following.
–Engine oil level is too high
–Engine oil viscosity
–Belt tension of power steering, alternator, A/C compressor, etc. is excessive
–Noise from engine
–Noise from transmission, etc.
2. Check for the cause of insufficient combustion. Refer to the following.
–Valve clearance malfunction
–Intake valve timing control function malfunction
–Camshaft sprocket installation malfunction, etc.
>> Repair or replace malfunctioning part, and then GO TO 30.
19. CHECK INTAKE SYSTEM
Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system
OK or NG
OK >> GO TO 21.
NG >> Repair or replace malfunctioning part, and then GO TO 20.
PBIB2332E

DTC P0550 PSP SENSOR
EC-185
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DTC P0550 PSP SENSORPFP:49763
Component DescriptionBBS005F1
Power steering pressure (PSP) sensor is installed to the power
steering high-pressure tube and detects a power steering load. This
sensor is a potentiometer which transforms the power steering load
into output voltage, and emits the voltage signal to the ECM. The
ECM controls the electric throttle control actuator and adjusts the
throttle valve opening angle to increase the engine speed and
adjusts the idle speed for the increased load.
CONSULT-II Reference Value in Data Monitor ModeBBS005F2
Specification data are reference values.
On Board Diagnosis LogicBBS005F3
The MI will not light up for this self-diagnosis.
NOTE:
If DTC P0550 is displayed with DTC P1229, first perform the trouble diagnosis for DTC P1229. Refer to
EC-233
.
DTC Confirmation ProcedureBBS005F4
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for at least 5 seconds.
4. If 1st trip DTC is detected, go to EC-187, "
Diagnostic Procedure"
.
WITHOUT CONSULT-II
1. Start engine and let it idle for at least 5 seconds.
2. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
3. Perform Diagnostic Test Mode II (Self-diagnostic results) with ECM.
4. If 1st trip DTC is detected, go to EC-187, "
Diagnostic Procedure" .
PBIB2134E
MONITOR ITEM CONDITION SPECIFICATION
PW/ST SIGNAL

Engine: After warming up, idle the
engineSteering wheel: Not being turned OFF
Steering wheel: Being turned ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0550
0550Power steering pressure
sensor circuitAn excessively low or high voltage from the
sensor is sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Power steering pressure sensor
SEF058Y

DTC P0550 PSP SENSOR
EC-187
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Specification 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.
Diagnostic ProcedureBBS005F6
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten two ground screws on the body.
Refer to E C - 111 , "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
12 WPower steering pressure
sensor[Engine is running]

Steering wheel: Being turned0.5 - 4.0V
[Engine is running]

Steering wheel: Not being turned0.4 - 0.8V
57 BSensor ground
(IAT sensor/ PSP sensor/
Refrigerant pressure sen-
sor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
65 LG/BSensor power supply
(Power steering pressure
sensor)[Ignition switch: ON]Approximately 5V
PBIB2160E

EC-188
[QR]
DTC P0550 PSP SENSOR

2. CHECK PSP SENSOR POWER SUPPLY CIRCUIT
1. Disconnect power steering pressure (PSP) sensor harness con-
nector.
2. Turn ignition switch ON.
3. Check voltage between PSP sensor terminal 3 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
3. CHECK PSP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between PSP sensor terminal 1 and ECM terminal 57.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK PSP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between PSP sensor terminal 2 and ECM terminal 12.
Refer to Wiring Diagram.
2. 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 PSP SENSOR
Refer to EC-189, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace PSP sensor.
PBIB2134E
Voltage: Approximately 5V
SEF509Y
Continuity should exist.
Continuity should exist.

DTC P0550 PSP SENSOR
EC-189
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6. CHECK INTERMITTENT INCIDENT
Refer to EC-105, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionBBS005F7
POWER STEERING PRESSURE SENSOR
1. Reconnect all harness connectors disconnected.
2. Start engine and let it idle.
3. Check voltage between ECM terminal 12 and ground under the
following conditions.
Removal and InstallationBBS005F8
POWER STEERING PRESSURE SENSOR
Refer to PS-39, "HYDRAULIC LINE" .
Condition Voltage
Steering wheel: Being turned fully 0.5 - 4.0V
Steering wheel: Not being turned 0.4 - 0.8V
MBIB0025E

DTC P1229 SENSOR POWER SUPPLY
EC-233
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DTC P1229 SENSOR POWER SUPPLYPFP:16119
On Board Diagnosis LogicBBS005GP
This self-diagnosis has the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MI lights up.
DTC Confirmation ProcedureBBS005GQ
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to EC-236, "
Diagnostic Procedure" .
WITHOUT CONSULT-II
1. Start engine and let it idle for 1 seconds.
2. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
3. Perform Diagnostic Test Mode II (Self-diagnostic results) with ECM.
4. If DTC is detected, go to EC-236, "
Diagnostic Procedure" .
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1229
1229Sensor power supply circuit
shortECM detects a voltage of power source
for sensor is excessively low or high.

Harness or connectors
(APP sensor 1 circuit is shorted.)
(PSP sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)

Accelerator pedal position sensor
(APP sensor 1)

Power steering pressure sensor

Refrigerant pressure sensor
Engine operation condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return
spring.
SEF058Y