Infiniti FX35, FX50 (S51). Manual - part 703

P0550 PSP SENSOR

EC-353

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

YES

>> INSPECTION END

NO

>> Replace power steering pressure sensor.

EC-354

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

P0603 ECM POWER SUPPLY

P0603 ECM POWER SUPPLY

Description

INFOID:0000000005236941

Battery voltage is supplied to the ECM even when the ignition switch
is turned OFF for the ECM memory function of the DTC memory, the
air-fuel ratio feedback compensation value memory, the idle air vol-
ume learning value memory, etc.

DTC Logic

INFOID:0000000005236942

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON and wait at least 10 second.

2.

Turn ignition switch OFF, wait at least 5 minutes.

3.

Turn ignition switch ON and wait at least 10 second.

4.

Repeat steps 2 and 3 for 5 times.

5.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-354, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000005236943

1.

CHECK ECM POWER SUPPLY

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Check the voltage between ECM harness connector terminals under the following conditions.

JMBIA0057ZZ

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0603

ECM power supply cir-
cuit

ECM back up RAM system does not function 
properly.

• Harness or connectors

[ECM power supply (back up) circuit is 
open or shorted.]

• ECM

P0603 ECM POWER SUPPLY

EC-355

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 2.

2.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors E3, F1
• 15 A fuse (No. 50)
• IPDM E/R harness connector E7
• Harness for open or short between ECM and battery

>> Repair or replace harness or connectors.

3.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-36, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace harness or connectors.

4.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Erase DTC.

3.

Perform DTC Confirmation Procedure.
See 

EC-354, "DTC Logic"

.

Is the 1st trip DTC P0603 displayed again?

YES

>> GO TO 5.

NO

>> INSPECTION END

5.

REPLACE ECM

1.

Replace ECM.

2.

Go to 

EC-23, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Require-

ment"

.

>> INSPECTION END

ECM

Voltage

+

–

Connector

Terminal

Connector

Terminal

F102

93

M107

128

Battery voltage

EC-356

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

P0605 ECM

P0605 ECM

Description

INFOID:0000000005236944

The ECM consists of a microcomputer and connectors for signal
input and output and for power supply. The ECM controls the engine.

DTC Logic

INFOID:0000000005236945

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A

1.

Turn ignition switch ON.

2.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-357, "Diagnosis Procedure"

.

NO

>> GO TO 3.

3.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B

1.

Turn ignition switch ON and wait at least 1 second.

2.

Turn ignition switch OFF, wait at least 10 seconds, and then turn it ON.

3.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-357, "Diagnosis Procedure"

.

NO

>> GO TO 4.

4.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION C

1.

Turn ignition switch ON and wait at least 1 second.

2.

Turn ignition switch OFF, wait at least 10 seconds, and then turn it ON.

3.

Repeat step 2 for 32 times.

4.

Check 1st trip DTC.

Is 1st trip DTC detected?

JMBIA0057ZZ

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0605

Engine control module

A)

ECM calculation function is malfunctioning.

• ECM

B)

ECM EEP-ROM system is malfunctioning.

C)

ECM self shut-off function is malfunctioning.