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Infiniti Q45 (FY33). Manual - part 205

SEF836U

SEF637U

SEF425U

DIAGNOSTIC PROCEDURE

INSPECTION START

CHECK POWER SUPPLY.
1. Turn ignition switch “OFF”.
2. Disconnect throttle position switch har-

ness connector.

3. Turn ignition switch “ON”.
4. Check voltage between terminal

and

engine ground with CONSULT-II or
tester.
Voltage: Battery voltage

Check the following.

Harness connectors

F63

M49

10A fuse

Harness for open or
short between throttle
position switch and fuse

If NG, repair harness or
connectors.

CHECK INPUT SIGNAL CIRCUIT.
1. Turn ignition switch “OFF”.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM

terminal

and terminal

Continuity should exist.
If OK, check harness for short to
ground and short to power.

Repair harness or connec-
tors.

ADJUST THROTTLE POSITION SWITCH.
Perform BASIC INSPECTION, EC-91.

CHECK COMPONENT
(Closed throttle position switch).
Refer to “COMPONENT INSPECTION” on
next page.

Replace throttle position
switch.

CHECK COMPONENT
(Throttle position sensor).
Refer to “COMPONENT INSPECTION” on
next page.

Replace throttle position
sensor.

Perform “TROUBLE DIAGNOSIS FOR
INTERMITTENT INCIDENT”, EC-117.

INSPECTION END

IDX

TROUBLE DIAGNOSIS FOR DTC P0510

Closed Throttle Position Switch (Cont’d)

EC-349

SEF793W

SEF266Y

SEF947U

COMPONENT INSPECTION

Closed throttle position switch (Built in throttle
position sensor)

Start engine and warm it up to normal operating temperature.

Stop engine (Ignition switch “OFF”).

Remove the vacuum hose connected to the throttle opener.

Connect suitable vacuum hose to the vacuum pump and the
opener.

Apply vacuum [more than −40.0 kPa (−300 mmHg, −11.81
inHg)] until the throttle drum becomes free from the rod of the
throttle opener.

6. Turn ignition switch “ON”.
7. Select “DATA MONITOR” mode with CONSULT-II.
8. Check indication of “CLSD THL/P SW”.

Measurement must be made with closed throttle position
switch installed in vehicle.

Throttle valve conditions

CLSD THL/P SW

Completely closed

Partially open or completely open

OFF

If NG, adjust closed throttle position switch. Refer to “Basic
Inspection”, EC-91.

9. If it is impossible to adjust closed throttle position switch

in “Basic Inspection”, replace closed throttle position
switch.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ OR ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

6. Disconnect closed throttle position switch harness con-

nector.

7. Check continuity between closed throttle position switch

terminals

and

Resistance measurement must be made with closed
throttle position switch installed in vehicle.

Throttle valve conditions

Continuity

Completely closed

Yes

Partially open or completely open

If NG, adjust closed throttle position switch. Refer to “Basic
Inspection”, EC-91.

8. If it is impossible to adjust closed throttle position switch

in “Basic Inspection”, replace closed throttle position
switch.

TROUBLE DIAGNOSIS FOR DTC P0510

Closed Throttle Position Switch (Cont’d)

EC-350

SEF793W

SEF266Y

SEF795W

Throttle position sensor

Start engine and warm it up to normal operating temperature.

Stop engine (Ignition switch “OFF”).

Remove the vacuum hose connected to the throttle opener.

Connect suitable vacuum hose to the vacuum pump and the
opener.

Apply vacuum [more than −40.0 kPa (−300 mmHg, −11.81
inHg)] until the throttle drum becomes free from the rod of the
throttle opener.

Turn ignition switch “ON”.

7. Select “DATA MONITOR” mode with CONSULT-II.
8. Check voltage of “THRTL POS SEN”.
Voltage measurement must be made with throttle posi-
tion sensor installed in vehicle.

Throttle valve conditions

THRTL POS SEN

Completely closed (a)

0.15 - 0.85

Partially open

Between (a) and (b)

Completely open (b)

3.5 - 4.7

If NG, adjust closed throttle position switch. Refer to “Basic
Inspection”, EC-91.

9. If it is impossible to adjust closed throttle position switch

in “Basic Inspection”, replace throttle position sensor.

7. Check voltage between ECM terminal

(Throttle posi-

tion sensor signal) and ground.

Voltage measurement must be made with throttle posi-
tion sensor installed in vehicle.

Throttle valve conditions

Voltage (V)

Completely closed

0.15 - 0.85

Partially open

Between (a) and (b)

Completely open

3.5 - 4.7

If NG, adjust closed throttle position switch. Refer to “Basic
Inspection”, EC-91.

8. If it is impossible to adjust closed throttle position switch

in “Basic Inspection”, replace throttle position sensor.

IDX

TROUBLE DIAGNOSIS FOR DTC P0510

Closed Throttle Position Switch (Cont’d)

EC-351

A/T Communication Line (P0600) and A/T
Diagnostic Communication Line (P1605)

This circuit line (LAN) controls the smooth shifting up and down of
A/T during the hard acceleration/deceleration. Pulse signals are
exchanged between ECM and TCM (P0600).
This circuit line is also used to communicate malfunction informa-
tion related to A/T (Automatic Transmission) is transferred through
the line (LAN circuit) from TCM to ECM (P1605).
Be sure to erase the malfunction information such as DTC not
only in TCM but also ECM after the A/T related repair.

ON BOARD DIAGNOSIS LOGIC

Diagnostic Trouble

Code No.

Malfunction is detected when ...

Check Items

(Possible Cause)

P0600
0504

ECM receives incorrect voltage from TCM continu-
ously.

Harness or connectors
(The communication line circuit between ECM and
TCM is open or shorted.)

TCM

Dead (Weak) battery

P1605
0804

Signal from TCM is not sent to ECM.

SEF261Y

DIAGNOSTIC TROUBLE CODE CONFIRMATION
PROCEDURE

NOTE
If “DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DURE” has been previously conducted, always turn ignition
switch “OFF” and wait at least 5 seconds before conducting
the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is more than 10.5V.

1) Turn ignition switch “ON”.
2) Select “DATA MONITOR” mode with CONSULT-II.
3) Start engine and let it idle for at least 2 seconds (P0600)

and 40 seconds (P1605).

4) If 1st trip DTC is detected, go to “DIAGNOSTIC

PROCEDURE”, EC-354.

Follow the procedure “With CONSULT-II” above.

TROUBLE DIAGNOSIS FOR DTC P0600, P1605

EC-352

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