Infiniti FX35, FX50 (S51). Manual - part 653

P0014, P0024 EVT CONTROL

EC-153

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

CAUTION:

Always drive vehicle at a safe speed.

3.

Check 1st trip DTC.

With GST

Follow the procedure “With CONSULT-III” above.

Is 1st trip DTC detected?

YES

>> Go to 

EC-153, "Diagnosis Procedure"

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000005236751

1.

CHECK FUNCTION OF EXHAUST VALVE TIMING (EVT) CONTROL

 With CONSULT-III

1.

Turn ignition switch ON.

2.

Select “EXH V/T ASSIGN ANGLE” in “ACTIVE TEST” mode with CONSULT-III.

3.

Start engine and keep the engine speed at 2,500 rpm, then touch “START”.

4.

Check that the values of “EXH/V TIM B1” and “EXH/V TIM B2” change when touching “UP” or “DOWN”.

 Without CONSULT-III

1.

Start engine and rev engine up above 1,500 rpm.

2.

Read the voltage signal between ECM harness connector terminals as follows with an oscilloscope.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> GO TO 2.

2.

CHECK EVT CONTROL MAGNET RETARDER

Refer to 

EC-154, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

3.

REPLACE EVT CONTROL MAGNET RETARDER

1.

Replace malfunctioning EVT control magnet retarder.

2.

Perform 

EC-27, "EXHAUST VALVE TIMING CONTROL LEARNING : Special Repair Requirement"

.

>> INSPECTION END

ENG SPEED

1,400 - 2,950 rpm (A constant rotation is maintained.)

COOLAN TEMP/S

More than 70

°

C (158

°

F)

Selector lever

1st or 2nd position

Driving location uphill

Driving vehicle uphill
(Increased engine load will help maintain the driving 
conditions required for this test.)

ECM

Voltage signal

+

–

Connector

Terminal

Connector

Terminal

F101

6

[EVT control magnet re-

tarder (bank 1) signal]

M107

128

7

[EVT control magnet re-

tarder (bank 2) signal]

JMBIA0034GB

EC-154

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

P0014, P0024 EVT CONTROL

4.

CHECK EVT CONTROL POSITION SENSOR

Refer to 

EC-369, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace malfunctioning EVT control position sensor.

5.

CHECK CRANKSHAFT POSITION SENSOR

Refer to 

EC-271, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Replace crankshaft position sensor.

6.

CHECK CAMSHAFT POSITION SENSOR

Refer to 

EC-277, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace malfunctioning camshaft position sensor.

7.

CHECK CAMSHAFT (EXH)

Check the following.
• Accumulation of debris to the signal plate of camshaft rear end
• Chipping signal plate of camshaft rear end

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Remove debris and clean the signal plate of camshaft

rear end or replace camshaft.

8.

CHECK TIMING CHAIN INSTALLATION

Check service records for any recent repairs that may cause timing chain misaligned.

Are there any service records that may cause timing chain misaligned?

YES

>> Check timing chain installation. Refer to 

EM-54, "Removal and Installation"

.

NO

>> GO TO 9.

9.

REPLACE EVT CONTROL PULLEY ASSEMBLY

1.

Replace exhaust valve timing control pulley assembly and EVT control magnet retarder.
Refer to 

EM-54, "Removal and Installation"

 and 

EM-70, "Removal and Installation"

.

2.

Perform 

EC-27, "EXHAUST VALVE TIMING CONTROL LEARNING : Special Repair Requirement"

.

>> INSPECTION END

10.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-36, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000005236752

1.

CHECK EXHAUST VALVE TIMING CONTROL MAGNET RETARDER

1.

Turn ignition switch OFF.

2.

Disconnect exhaust valve timing control magnet retarder harness connector.

3.

Check resistance between exhaust valve timing control magnet retarder terminals as follows.

JMBIA0059ZZ

P0014, P0024 EVT CONTROL

EC-155

< 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

>> INSPECTION END

NO

>> GO TO 2.

2.

REPLACE EXHAUST VALVE TIMING CONTROL MAGNET RETARDER

1.

Replace malfunctioning exhaust valve timing control magnet retarder.

2.

Perform 

EC-27, "EXHAUST VALVE TIMING CONTROL LEARNING : Special Repair Requirement"

.

>> INSPECTION END

Terminals

Resistance

1 and 2

9.0 - 11.0 

Ω

 [at 20

°

C (68

°

F)]

EC-156

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

Description

INFOID:0000000005236753

SYSTEM DESCRIPTION

The ECM performs ON/OFF duty control of the A/F sensor 1 heater corresponding to the engine operating
condition to keep the temperature of A/F sensor 1 element within the specified range.

DTC Logic

INFOID:0000000005236754

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.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 10.5 V and 16 V at
idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine and let it idle for at least 10 seconds.

2.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-157, "Diagnosis Procedure"

.

NG

>> INSPECTION END

Sensor

Input signal to ECM

ECM function

Actuator

Camshaft position sensor
Crankshaft position sensor

Engine speed

Air fuel ratio (A/F) sensor 1 
heater control

Air fuel ratio (A/F) sensor 1 
heater

Mass air flow sensor

Amount of intake air

 DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0031

Air fuel ratio (A/F) sensor 
1 heater (bank 1) control 
circuit low

The current amperage in the A/F sensor 1 heater 
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM 
through the A/F sensor 1 heater.)

• Harness or connectors

(The A/F sensor 1 heater circuit is 
open or shorted.)

• A/F sensor 1 heater

P0032

Air fuel ratio (A/F) sensor 
1 heater (bank 1) control 
circuit high

The current amperage in the A/F sensor 1 heater 
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM 
through the A/F sensor 1 heater.)

• Harness or connectors

(The A/F sensor 1 heater circuit is 
shorted.)

• A/F sensor 1 heater

P0051

Air fuel ratio (A/F) sensor 
1 heater (bank 2) control 
circuit low

The current amperage in the A/F sensor 1 heater 
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM 
through the A/F sensor 1 heater.)

• Harness or connectors

(The A/F sensor 1 heater circuit is 
open or shorted.)

• A/F sensor 1 heater

P0052

Air fuel ratio (A/F) sensor 
1 heater (bank 2) control 
circuit high

The current amperage in the A/F sensor 1 heater 
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM 
through the A/F sensor 1 heater.)

• Harness or connectors

(The A/F sensor 1 heater circuit is 
shorted.)

• A/F sensor 1 heater