Infiniti QX56 (JA60). Manual - part 411

EC-296

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P1140, P1145 IVT CONTROL POSITION SENSOR

Refer to 

EC-85, "Ground Inspection"

.

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace ground connections.

2.

CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR POWER SUPPLY CIRCUIT

1. Disconnect intake valve timing control position sensor harness connector.

2. Turn ignition switch ON.

3. Check voltage between intake valve timing control position sen-

sor terminal 3 and ground with CONSULT-III or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E2, F32

• Harness for open or short between intake valve timing control position sensor and IPDM E/R

• Harness for open or short between intake valve timing control position sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.

CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR GROUND CIRCUIT FOR OPEN AND

SHORT
1. Turn ignition switch OFF.

2. Check harness continuity between intake valve timing control position sensor terminal 1 and ground.

Refer to Wiring Diagram.

BBIA0354E

1.

Intake valve timing control position 
sensor (bank 2)

2.

Intake valve timing control solenoid 
valve (bank 2)

3.

Drive belt

4.

Radiator hose

5.

Intake valve timing control solenoid 
valve (bank 1)

6.

Intake valve timing control position 
sensor (bank 1)

Voltage: Battery voltage

BBIA0771E

PBIB2613E

P1140, P1145 IVT CONTROL POSITION SENSOR

EC-297

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3. Also check harness for short to power. 
OK or NG

OK

>> GO TO 6.

NG

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E2, F32

• Harness for open or short between intake valve timing control position sensor and ground

>> Repair open circuit or short to power in harness or connectors.

6.

CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN

AND SHORT

1. Disconnect ECM harness connector.

2. Check harness continuity between the following;

ECM terminal 72 and intake valve timing control position sensor (Bank 1) terminal 2 or 

ECM terminal 53 and intake valve timing control position sensor (Bank 2) terminal 2.

Refer to Wiring Diagram.

3. Also check harness for short to ground and short to power. 
OK or NG

OK

>> GO TO 7.

NG

>> Repair open circuit or short to ground or short to power in harness or connectors.

7.

CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR

Refer to 

EC-298, "Component Inspection"

.

OK or NG

OK

>> GO TO 8.

NG

>> Replace malfunctioning intake valve timing control position sensor. Refer to 

EC-495

.

8.

CHECK CRANKSHAFT POSITION SENSOR (POS)

Refer to 

EC-203, "Component Inspection"

.

OK or NG

OK

>> GO TO 9.

NG

>> Replace crankshaft position sensor (POS).

9.

CHECK CAMSHAFT POSITION SENSOR (PHASE)

Refer to 

EC-207, "Component Inspection"

.

OK or NG

OK

>> GO TO 10.

NG

>> Replace camshaft position sensor (PHASE). Refer to 

EC-495

.

10.

CHECK CAMSHAFT SPROCKET

Check accumulation of debris to the signal pick-up portion of the camshaft sprocket. Refer to 

EM-62, "Inspec-

tion after Installation"

.

OK or NG

OK

>> GO TO 11.

NG

>> Remove debris and clean the signal pick-up cutout of camshaft sprocket.

11.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-35, "How to Check Terminal"

 and 

GI-38, "Intermittent Incident"

.

Continuity should exist.

Continuity should exist.

EC-298

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P1140, P1145 IVT CONTROL POSITION SENSOR

>> INSPECTION END

Component Inspection

INFOID:0000000005149340

INTAKE VALVE TIMING CONTROL POSITION SENSOR

1. Disconnect intake valve timing control position sensor harness connector.
2. Loosen the fixing bolt of the sensor.
3. Remove the sensor.
4. Visually check the sensor for chipping.

5. Check resistance as shown below.

6. If NG, replace intake valve timing control position sensor. Refer

to 

EC-495

.

SEF362Z

Terminal No. (Polarity)

Resistance 

Ω [at 25°C (77°F)]

3 (+) - 1 (-)

Except 0 or 

∞

2 (+) - 1 (-)

3 (+) - 2 (-)

JMBIA0600ZZ

P1148, P1168 CLOSED LOOP CONTROL

EC-299

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P1148, P1168 CLOSED LOOP CONTROL

On Board Diagnosis Logic

INFOID:0000000005149341

These self-diagnoses have the one trip detection logic.

DTC P1148 or P1168 is displayed with another DTC for air fuel ratio (A/F) sensor 1.

Perform the trouble diagnosis for the corresponding DTC.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1148
1148
(Bank 1)

Closed loop control 
function

The closed loop control function for bank 1 does 
not operate even when vehicle is driving in the 
specified condition.

• Harness or connectors

[The air fuel ratio (A/F) sensor 1 circuit is 
open or shorted.]

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

P1168
1168
(Bank 2)

The closed loop control function for bank 2 does 
not operate even when vehicle is driving in the 
specified condition.