Infiniti I35 (A33). Manual - part 41

CHECK DTC

Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-158.

OK or NG

INSPECTION END

GO TO 5.

CHECK TCM INSPECTION

1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.

OK or NG

INSPECTION END

Repair or replace damaged parts.

IDX

DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE

Diagnostic Procedure (Cont’d)

AT-161

Description

NHAT0061

This is an OBD-II self-diagnostic item and not available in TCM
self-diagnosis.

This malfunction will not be detected while the A/T CHECK
indicator lamp is indicating another self-diagnosis malfunction.

This malfunction is detected when the A/T does not shift into
fourth gear position or the torque converter clutch does not
lock up as instructed by the TCM. This is not caused by elec-
trical malfunction (circuits open or shorted) but by mechanical
malfunction such as control valve sticking, improper solenoid
valve operation, malfunctioning oil pump or torque converter
clutch, etc.

CONSULT-II REFERENCE VALUE IN DATA MONITOR
MODE

NHAT0061S01

Remarks: Specification data are reference values.

Monitor item

Condition

Specification

Torque converter clutch
solenoid valve duty

Lock-up OFF

Lock-up ON

Approximately 4%

Approximately 94%

TCM TERMINALS AND REFERENCE VALUE

NHAT0061S02

Remarks: Specification data are reference values.

Terminal

No.

Wire color

Item

Condition

Judgement

standard

(Approx.)

G/R

Line pressure sole-
noid valve

When releasing accelerator pedal after warm-
ing up engine.

1.5 - 3.0V

When depressing accelerator pedal fully after
warming up engine.

W/B

Line pressure sole-
noid valve
(with dropping
resistor)

When releasing accelerator pedal after warm-
ing up engine.

4 - 14V

When depressing accelerator pedal fully after
warming up engine.

G/B

Torque converter
clutch solenoid
valve

When A/T performs lock-up.

8 - 15V

When A/T does not perform lock-up.

On Board Diagnosis Logic

NHAT0228

This diagnosis monitors actual gear position by checking the torque
converter slip ratio calculated by TCM as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is much lower than the position (4th)
supposed by TCM, the slip ratio will be much less than normal. In
case the ratio does not reach the specified value, TCM judges this
diagnosis malfunction.

DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)

Description

AT-162

This malfunction will be caused when shift solenoid valve B is stuck
closed.
Gear positions supposed by TCM are as follows.
In case of gear position with no malfunctions: 1, 2, 3 and 4 posi-
tions
In case of gear position with shift solenoid valve B stuck closed: 1,
2, 2 and 1* positions to each gear position above
*: P0744 is detected.
Diagnostic trouble code A/T TCC S/V FNCTN with CONSULT-II or
P0744 without CONSULT-II is detected when A/T cannot perform
lock-up even if electrical circuit is good.

Possible Cause

NHAT0229

Check the following items.

Line pressure solenoid valve

Torque converter clutch solenoid valve

Each clutch

Hydraulic control circuit

SAT014K

SAT860K

SAT021J

Diagnostic Trouble Code (DTC) Confirmation
Procedure

NHAT0230

CAUTION:

Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously conducted,
always turn ignition switch OFF and wait at least 10 seconds before
conducting the next test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.

WITH CONSULT-II

NHAT0230S01

Start engine and select “DATA MONITOR” mode for “A/T” with
CONSULT-II.

Make sure that output voltage of A/T fluid temperature sensor
is within the range below.
FLUID TEMP SEN: 0.4 - 1.5V
If out of range, drive vehicle to decrease voltage (warm up the
fluid) or stop engine to increase voltage (cool down the fluid).

Select “TCC S/V FNCTN P0744” of “DTC WORK SUPPORT”
mode for “A/T” with CONSULT-II and touch “START”.

Accelerate vehicle to more than 80 km/h (50 MPH) and main-
tain the following condition continuously until “TESTING” has
turned to “COMPLETE”. (It will take approximately 30 seconds
after “TESTING” shows.)
THROTTLE POSI: 1.0/8 - 2.0/8 (at all times during step 4)
Selector lever: D position
TCC S/V DUTY: More than 94%
VHCL/S SE·A/T: Constant speed of more than 80 km/h (50
MPH)

Check that “GEAR” shows “4”.

For shift schedule, refer to SDS, AT-381.

If “TESTING” does not appear on CONSULT-II for a long
time, select “SELF-DIAG RESULTS”. In case a 1st trip DTC

IDX

DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)

On Board Diagnosis Logic (Cont’d)

AT-163

other than P0744 is shown, refer to applicable “TROUBLE
DIAGNOSIS FOR DTC”.

Make sure that “OK” is displayed. (If “NG” is displayed, refer
to “DIAGNOSTIC PROCEDURE”.)
Refer to AT-166, “DIAGNOSTIC PROCEDURE”.
Refer to AT-381, “Shift Schedule”.

WITH GST

NHAT0230S02

Follow the procedure “With CONSULT-II”.

DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)

Diagnostic Trouble Code (DTC) Confirmation Procedure (Cont’d)

AT-164

Content .. 39 40 41 42 ..