Infiniti G37 Coupe. Manual - part 1240

POWER STEERING SOLENOID VALVE

STC-11

< COMPONENT DIAGNOSIS >

[WITHOUT 4WAS]

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POWER STEERING SOLENOID VALVE

Description

INFOID:0000000001666273

• Power steering solenoid valve controls the power steering oil pressure in the gear housing assembly.

Diagnosis Procedure

INFOID:0000000001666274

1.

CHECK POWER STEERING SOLENOID VALVE SIGNAL

1.

Turn the ignition switch OFF.

2.

Check signal between power steering control unit harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> GO TO 4.

2.

CHECK HARNESS BETWEEN POWER STEERING SOLENOID VALVE AND POWER STEERING CON-

TROL UNIT

1.

Turn the ignition switch OFF.

2.

Disconnect power steering solenoid valve harness connector.

3.

Disconnect power steering control unit harness connector.

4.

Check the continuity between power steering solenoid valve harness connector and the power steering
control unit harness connector.

Also check harness for short to ground and short to power.

Is the inspection result normal?

 YES

>> GO TO 3.

 NO

>> Repair or replace damaged parts.

3.

CHECK POWER STEERING SOLENOID VALVE

1.

Check resistance between power steering solenoid valve connector terminals.

2.

Check power steering solenoid valve connector by listening for its operation sound while applying battery
voltage to power steering solenoid valve connector F45 terminals 1 (positive) and 2 (negative).

Is the inspection result normal?

 YES

>> GO TO 4.

 NO

>> Replace gear-sub assembly. Refer to 

ST-26, "Exploded View"

.

4.

CHECK TERMINALS AND HARNESS CONNECTORS

• Check power steering control unit pin terminals for damage or loose connection with harness connector.
• Check power steering solenoid valve pin terminals for damage or loose connection with harness connector.

Power steering control unit

Value (Approx.)

Connector

Terminal

Condition

M108

 1 – Ground

Vehicle speed: 0 km/h (0 MPH)
(Engine is running)

4.4 – 6.6 V

Vehicle speed: 100 km/h (62 MPH)

2.4 – 3.6 V

Power steering solenoid 

valve

Power steering control unit

Continuity

Connector

Terminal

Connector

Terminal

F45

1

M108

1

Existed

F45

2

M108

5

Existed

Power steering solenoid valve

Resistance (Approx.)

Connector

Terminal

F45

1 – 2

4 – 6 

Ω

STC-12

< COMPONENT DIAGNOSIS >

[WITHOUT 4WAS]

POWER STEERING SOLENOID VALVE

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Repair or replace damaged parts.

Component Inspection

INFOID:0000000001666275

1.

CHECK POWER STEERING SOLENOID VALVE

1.

Turn the ignition switch OFF.

2.

Disconnect power steering solenoid valve harness connector.

3.

Check resistance between power steering solenoid valve connector terminals.

4.

Check power steering solenoid valve connector by listening for its operation sound while applying battery
voltage to power steering solenoid valve connector F45 terminals 1 (positive) and 2 (negative).

Is the inspection result normal?

 YES

>> INSPECTION END

 NO

>> Replace gear-sub assembly. Refer to 

ST-26, "Exploded View"

.

Power steering solenoid valve

Resistance (Approx.)

Connector

Terminal

F45

1 – 2

4 – 6 

Ω

ENGINE SPEED SIGNAL CIRCUIT

STC-13

< COMPONENT DIAGNOSIS >

[WITHOUT 4WAS]

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ENGINE SPEED SIGNAL CIRCUIT

Description

INFOID:0000000001666276

• ECM sends engine speed signal to power steering control unit.

Diagnosis Procedure

INFOID:0000000001666277

1.

PERFORM ECM SELF-DIAGNOSIS

With CONSULT-III

Perform ECM self-diagnosis.

Is any error system detected?

YES

>> Check the error system.

NO

>> GO TO 2.

2.

CHECK HARNESS BETWEEN ECM AND POWER STEERING CONTROL UNIT

1.

Turn the ignition switch OFF.

2.

Disconnect ECM harness connectors.

3.

Disconnect power steering control unit harness connector.

4.

Check continuity between ECM harness connector and power steering control unit harness connector.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace damaged parts.

3.

CHECK ENGINE SPEED SIGNAL (1)

1.

Turn the ignition switch OFF.

2.

Connect ECM harness connectors.

3.

Check signal between ECM harness connector and ground with oscilloscope.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 4.

ECM

Power steering control unit

Continuity

Connector

Terminal

Connector

Terminal

M107

110

M108

10

Existed

ECM

Value (Approx.)

Connector

Terminal

Condition

M107

110 – Ground

Engine speed: At idle
(Warm-up condition)

Engine speed: Approx. 2,000 rpm
(Warm-up condition)

PBIA3654J

PBIA3655J

STC-14

< COMPONENT DIAGNOSIS >

[WITHOUT 4WAS]

ENGINE SPEED SIGNAL CIRCUIT

NO

>> Replace ECM. Refer to 

EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT

(ECM) : Description"

.

4.

CHECK ENGINE SPEED SIGNAL (2)

1.

Turn the ignition switch OFF.

2.

Connect power steering control unit harness connector.

3.

Check signal between power steering control unit harness connector and ground with oscilloscope.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace power steering control unit. Refer to 

STC-24, "Exploded View"

.

5.

CHECK TERMINALS AND HARNESS CONNECTORS

• Check power steering control unit pin terminals for damage or loose connection with harness connector.
• Check ECM pin terminals for damage or loose connection with harness connector.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Repair or replace damaged parts.

Power steering control unit

Value (Approx.)

Connector

Terminal

Condition

M108

 10 – Ground

Engine speed: At idle
(Warm-up condition)

Engine speed: Approx. 2,000 rpm
(Warm-up condition)

PBIA3654J

PBIA3655J