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Infiniti Q45 (FY33). Manual - part 219

SEF793X

SEF894V

SEF157T

SEF069T

SEF305T

SEARCH FOR MALFUNCTIONING CIR-
CUIT.
1. Start engine and let it idle.

2. Perform “POWER BALANCE” in

“ACTIVE TEST” mode with
CONSULT-II.

3. Search for circuit which does

not produce a momentary
engine speed drop.

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

2. Check output signal voltage

between ECM terminals

and

ground with oscilloscope.

3. Search for circuit that signal

voltage does not match to
“DATA” in “ECM INSPECTION
TABLE”.

CHECK POWER SUPPLY-2.
1. Turn ignition switch “OFF”.
2. Disconnect ignition coil harness con-

nector(s).

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

coil harness connector terminal

and

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

Check the following.

Harness for open or
short between ignition
coil and ECM relay

If NG, repair harness or
connectors.

CHECK GROUND CIRCUIT.
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground

screws.

3. Check harness continuity between igni-

tion coil harness connector terminal

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

Check the following.

Harness connectors

F61

F62

Check for open or short
between ignition coil and
engine ground

If NG, repair open circuit or
short to power in harness
or connectors.

(Go to next page.)

IDX

TROUBLE DIAGNOSIS FOR DTC P1320

Ignition Signal (Cont’d)

EC-405

SEF377U

SEF887Q

SEF439U

CHECK OUTPUT SIGNAL CIRCUIT-2.
1. Disconnect ECM harness connector.
2. Check harness continuity between each

ignition coil harness connector terminal

and each ECM harness connector

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

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

CHECK COMPONENT
(Ignition coil with power transistor).
Refer to “COMPONENT INSPECTION”.

Replace ignition coil
assembly.

Perform “TROUBLE DIAGNOSIS FOR
INTERMITTENT INCIDENT”.

INSPECTION END

SEF307T

COMPONENT INSPECTION

Ignition coil with power transistor

Disconnect ignition coil with power transistor harness connec-
tor.

Check ignition coil with power transistor for resistance between
terminals

and

Terminals

Resistance

Result

and

Not 0

Ω

If NG, replace ignition coil with power transistor assembly.

TROUBLE DIAGNOSIS FOR DTC P1320

Ignition Signal (Cont’d)

EC-406

SEF956N

Crankshaft Position Sensor (CKPS) (OBD)
(COG)

COMPONENT DESCRIPTION

The crankshaft position sensor (OBD) is located on the transmis-
sion housing facing the gear teeth (cogs) of the drive plate. It
detects the fluctuation of the engine revolution.
The sensor consists of a permanent magnet, core and coil.
When the engine is running, the high and low parts of the teeth
cause the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor
changes.
The ECM receives the voltage signal and detects the fluctuation of
the engine revolution.
This sensor is not directly used to control the engine system. It is
used only for the on board diagnosis of misfire.

ECM TERMINALS AND REFERENCE VALUE

Specification data are reference values, and are measured between each terminal and ground.

CAUTION:

Do not use ECM ground terminals when measuring voltage. Doing so may result in damage to the
ECM’s transistor. Use a ground other than ECM terminals such as the body ground.

TER-

MINAL

NO.

WIRE

COLOR

ITEM

CONDITION

DATA

(AC voltage)

B/R

Crankshaft position sen-
sor (OBD)

Engine is running. (Warmed-up condition)

Idle speed

Approximately 1.7V
(AC voltage)

SEF391X

Engine is running. (Warmed-up condition)

Engine speed is 2,000 rpm.

Approximately 0V

SEF546T

ON BOARD DIAGNOSIS LOGIC

Diagnostic Trouble

Code No.

Malfunction is detected when ....

Check Items

(Possible Cause)

P1336
0905

Chipping of the signal plate (on drive plate) gear
teeth (cogs) is detected by the ECM.

Harness or connectors

Crankshaft position sensor (POS)

Signal plate (drive plate)

Dead (Weak) battery

IDX

TROUBLE DIAGNOSIS FOR DTC P1336

EC-407

SEF392X

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 at idle.

1) Turn ignition switch “ON” and select “DATA MONITOR”

mode with CONSULT-II.

2) Start engine and run it for at least 3 minutes at idle

speed.

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

PROCEDURE”, EC-410.

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

Follow the procedure “With CONSULT-II” above.

TROUBLE DIAGNOSIS FOR DTC P1336

Crankshaft Position Sensor (CKPS) (OBD)
(COG) (Cont’d)

EC-408

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