Nissan Frontier D40. Manual - part 396

P0507 ISC SYSTEM

EC-275

< COMPONENT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

OK

>> GO TO 3.

NG

>> Discover air leak location and repair.

3.

REPLACE ECM

1.

Stop engine.

2.

Replace ECM.

3.

Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs. Refer to

SEC-7, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement"

.

4.

Perform 

EC-24, "VIN Registration"

.

5.

Perform 

EC-24, "Accelerator Pedal Released Position Learning"

.

6.

Perform 

EC-24, "Throttle Valve Closed Position Learning"

.

7.

Perform 

EC-24, "Idle Air Volume Learning"

.

>> INSPECTION END

EC-276

< COMPONENT DIAGNOSIS >

[QR25DE]

P0550 PSP SENSOR

P0550 PSP SENSOR

Component Description

INFOID:0000000005273282

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.

On Board Diagnosis Logic

INFOID:0000000005273283

The MIL will not light up for this diagnosis.
NOTE:
If DTC P0550 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to

EC-285

.

DTC Confirmation Procedure

INFOID:0000000005273284

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-III

1.

Start engine and let it idle for at least 5 seconds.

2.

Check 1st trip DTC.

3.

If 1st trip DTC is detected, go to 

EC-276, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000005273285

1.

CHECK GROUND CONNECTIONS

1.

Turn ignition switch OFF.

2.

Loosen and retighten two ground screws on the body. Refer to

EC-90, "Ground Inspection"

 .

OK or NG

OK

>> GO TO 2.

BBIA0621E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0550
0550

Power steering pressure 
sensor circuit

An 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

BBIA0614E

P0550 PSP SENSOR

EC-277

< COMPONENT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

NG

>> Repair or replace ground connections.

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-III or tester.

OK or NG

OK

>> GO TO 3.

NG

>> Repair open circuit, 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 67.
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, 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 ECM terminal 12 and PSP sensor terminal 2.
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, short to ground or short to power in harness or connectors.

5.

CHECK PSP SENSOR

Refer to 

EC-278, "Component Inspection"

.

OK or NG

OK

>> GO TO 6.

NG

>> Replace PSP sensor.

6.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-46, "Intermittent Incident"

.

BBIA0621E

Voltage: Approximately 5V

SEF479Y

Continuity should exist.

Continuity should exist.

EC-278

< COMPONENT DIAGNOSIS >

[QR25DE]

P0550 PSP SENSOR

>> INSPECTION END

Component Inspection

INFOID:0000000005273286

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.

Condition

Voltage

Steering wheel: Being turned

0.5 - 4.5V

Steering wheel: Not being turned

0.4 - 0.8V

MBIB0025E