Infiniti G37 Coupe. Manual - part 551

P1217 ENGINE OVER TEMPERATURE

EC-385

< COMPONENT DIAGNOSIS >

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Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
Is the coolant level in the reservoir tank and/or radiator below the
proper range?

YES

>> Go to 

EC-385, "Diagnosis Procedure"

.

NO

>> GO TO 2.

2.

PERFORM COMPONENT FUNCTION CHECK-II

Confirm whether customer filled the coolant or not.

Did customer fill the coolant?

YES

>> Go to 

EC-385, "Diagnosis Procedure"

.

NO

>> GO TO 3.

3.

PERFORM COMPONENT FUNCTION CHECK-III

With CONSULT-III

1.

Turn ignition switch ON.

2.

Perform “FAN DUTY CONTROL” in “ACTIVE TEST” mode with CONSULT-III.

3.

Make sure that cooling fan speed varies according to the percent.

Without CONSULT-III

Perform IPDM E/R auto active test and check cooling fan motors operation, refer to 

PCS-11, "Diagnosis

Description"

.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to 

EC-385, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000001734192

1.

CHECK COOLING FAN OPERATION

With CONSULT-III

1.

Turn ignition switch ON.

2.

Perform “FAN DUTY CONTROL” in “ACTIVE TEST” mode with CONSULT-III.

3.

Make sure that cooling fan speed varies according to the percent.

Without CONSULT-III

1.

Perform IPDM E/R auto active test and check cooling fan motors operation, refer to 

PCS-11, "Diagnosis

Description"

.

2.

Make sure that cooling fan operates.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Go to 

EC-481, "Diagnosis Procedure"

.

2.

CHECK COOLING SYSTEM FOR LEAK-I

Check cooling system for leak. Refer to 

CO-8, "Inspection"

.

Is leakage detected?

YES

>> GO TO 3.

NO

>> GO TO 4.

3.

CHECK COOLING SYSTEM FOR LEAK-II

Check the following for leak.
• Hose
• Radiator
• Water pump

SEF621W

EC-386

< COMPONENT DIAGNOSIS >

[VQ37VHR]

P1217 ENGINE OVER TEMPERATURE

>> Repair or replace malfunctioning part.

4.

CHECK RADIATOR CAP

Check radiator cap. Refer to 

CO-12, "RADIATOR CAP : Inspection"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace radiator cap.

5.

CHECK THERMOSTAT

Check thermostat. Refer to 

CO-23, "Inspection"

.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Replace thermostat

6.

CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to 

EC-186, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace engine coolant temperature sensor.

7.

CHECK MAIN 12 CAUSES

If the cause cannot be isolated, check the following.

*1: Turn the ignition switch ON.

*2: Engine running at 3,000 rpm for 10 minutes.

*3: Drive at 90 km/h (55 MPH) for 30 minutes and then let idle for 10 minutes.

*4: After 60 minutes of cool down time.

Engine

Step

Inspection item

Equipment

Standard

Reference page

OFF

1

• Blocked radiator
• Blocked condenser
• Blocked radiator grille
• Blocked bumper

• Visual

No blocking

—

2

• Coolant mixture

• Coolant tester

50 - 50% coolant mixture

3

• Coolant  level

• Visual

Coolant up to MAX level in 
reservoir tank and radiator 
filler neck

CO-8, "Inspection"

4

• Radiator cap

• Pressure tester

107 kPa

(1.1 kg/cm

2

, 16 psi) (Limit)

CO-12, "RADIATOR CAP 
: Inspection"

ON*

2

5

• Coolant leaks

• Visual

No leaks

CO-8, "Inspection"

ON*

2

6

• Thermostat

• Touch the upper and 

lower radiator hoses

Both hoses should be hot

CO-23, "Inspection"

ON*

1

7

• Cooling fan

• CONSULT-III

Operating

EC-481, "Component 
Function Check"

OFF

8

• Combustion gas leak

• Color checker chemical 

tester 4 Gas analyzer

Negative

—

ON*

3

9

• Coolant temperature 

gauge

• Visual

Gauge less than 3/4 when 
driving

—

• Coolant overflow to res-

ervoir tank

• Visual

No overflow during driving 
and idling

CO-8, "Inspection"

OFF*

4

10

• Coolant return from res-

ervoir tank to radiator

• Visual

Should be initial level in 
reservoir tank

CO-8, "Inspection"

OFF

11

• Cylinder head

• Straight gauge feeler 

gauge

0.1 mm (0.004 in) Maxi-
mum distortion (warping)

EM-106, "Inspection"

12

• Cylinder block and pis-

tons

• Visual

No scuffing on cylinder 
walls or piston

EM-120, "Inspection"

P1217 ENGINE OVER TEMPERATURE

EC-387

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For more information, refer to 

CO-3, "Troubleshooting Chart"

.

>> INSPECTION END

EC-388

< COMPONENT DIAGNOSIS >

[VQ37VHR]

P1225, P1234 TP SENSOR

P1225, P1234 TP SENSOR

Description

INFOID:0000000001910843

Electric throttle control actuator consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement. 
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.

DTC Logic

INFOID:0000000001734194

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing 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 more than 10V at idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Turn ignition switch OFF and wait at least 10 seconds.

3.

Turn ignition switch ON.

4.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-388, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734195

1.

CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.

Turn ignition switch OFF.

2.

Remove the intake air duct.

PBIB0145E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1225

Closed throttle position learning per-
formance (bank 1)

Closed throttle position learning value 
is excessively low.

• Electric throttle control actuator

(TP sensor 1 and 2)

P1234

Closed throttle position learning per-
formance (bank 2)