engine control NISSAN TEANA 2003 Service Manual

CVT-4 On Board Diagnosis Logic ....................................143
Possible Cause .....................................................143
DTC Confirmation Procedure ...............................143
WITH CONSULT-II ............................................143
Diagnostic Procedure ...........................................144
DTC P1726 ELECTRIC THROTTLE CONTROL
SYSTEM ..................................................................145
Description ............................................................145
On Board Diagnosis Logic ....................................145
Possible Cause .....................................................145
DTC Confirmation Procedure ...............................145
WITH CONSULT-II ............................................145
Diagnostic Procedure ...........................................146
DTC P1740 LOCK-UP SELECT SOLENOID VALVE
CIRCUIT ..................................................................147
Description ............................................................147
CONSULT-II Reference Value ..............................147
On Board Diagnosis Logic ....................................147
Possible Cause .....................................................147
DTC Confirmation Procedure ...............................147
WITH CONSULT-II ............................................147
Wiring Diagram — CVT — L/USSV ......................148
Diagnostic Procedure ...........................................149
Component Inspection ..........................................151
LOCK-UP SELECT SOLENOID VALVE ............151
DTC P1745 LINE PRESSURE CONTROL .............152
Description ............................................................152
On Board Diagnosis Logic ....................................152
Possible Cause .....................................................152
DTC Confirmation Procedure ...............................152
WITH CONSULT-II ............................................152
Diagnostic Procedure ...........................................152
DTC P1777 STEP MOTOR - CIRCUIT ...................153
Description ............................................................153
CONSULT-II Reference Value ..............................153
On Board Diagnosis Logic ....................................153
Possible Cause .....................................................153
DTC Confirmation Procedure ...............................153
WITH CONSULT-II ............................................153
Wiring Diagram — CVT — STM ...........................154
Diagnostic Procedure ...........................................155
Component Inspection ..........................................156
STEP MOTOR ...................................................156
DTC P1778 STEP MOTOR - FUNCTION ...............157
Description ............................................................157
CONSULT-II Reference Value ..............................157
On Board Diagnosis Logic ....................................157
Possible Cause .....................................................157
DTC Confirmation Procedure ...............................157
WITH CONSULT-II ............................................157
Diagnostic Procedure ...........................................158
CVT INDICATOR CIRCUIT .....................................159
Description ............................................................159
CONSULT-II Reference Value ..............................159
Diagnostic Procedure ...........................................159
CVT INDICATOR SYMPTOM CHART ...............159
TROUBLE DIAGNOSIS FOR SYMPTOMS ............160Wiring Diagram — CVT — NONDTC ...................160
CVT Indicator Lamp Does Not Come On ..............164
SYMPTOM: ........................................................164
DIAGNOSTIC PROCEDURE .............................164
Engine Cannot Be Started in “P” or “N” Position ...165
SYMPTOM: ........................................................165
DIAGNOSTIC PROCEDURE .............................165
In “P” Position, Vehicle Moves Forward or Backward
When Pushed .......................................................166
SYMPTOM: ........................................................166
DIAGNOSTIC PROCEDURE .............................166
In “N” Position, Vehicle Moves ..............................166
SYMPTOM: ........................................................166
DIAGNOSTIC PROCEDURE .............................166
Large Shock “N” → “R” Position ...........................167
SYMPTOM: ........................................................167
DIAGNOSTIC PROCEDURE .............................167
Vehicle Does Not Creep Backward in “R” Position .168
SYMPTOM: ........................................................168
DIAGNOSTIC PROCEDURE .............................168
Vehicle Does Not Creep Forward in “D” Position ..169
SYMPTOM: ........................................................169
DIAGNOSTIC PROCEDURE .............................169
CVT Does Not Shift ...............................................170
SYMPTOM: ........................................................170
DIAGNOSTIC PROCEDURE .............................170
Cannot Be Changed to Manual Mode ...................171
SYMPTOM: ........................................................171
DIAGNOSTIC PROCEDURE .............................171
CVT Does Not Shift in Manual Mode ....................171
SYMPTOM: ........................................................171
DIAGNOSTIC PROCEDURE .............................171
Vehicle Does Not Decelerate by Engine Brake .....172
SYMPTOM: ........................................................172
DIAGNOSTIC PROCEDURE .............................172
TRANSMISSION CONTROL MODULE ..................174
Removal and Installation .......................................174
COMPONENTS .................................................174
REMOVAL ..........................................................174
INSTALLATION ..................................................175
SHIFT CONTROL SYSTEM ....................................176
Removal and Installation .......................................176
CONTROL DEVICE COMPONENTS ................176
CONTROL CABLE COMPONENTS ..................177
REMOVAL ..........................................................177
INSTALLATION ..................................................178
Adjustment of CVT Position ..................................178
Checking of CVT Position .....................................179
CVT SHIFT LOCK SYSTEM ...................................180
Description ............................................................180
Shift Lock System Electrical Parts Location ..........180
Wiring Diagram — CVT — SHIFT ........................181
Shift Lock Control Unit Reference Values .............183
SHIFT LOCK HARNESS CONNECTOR TERMI-
NALS LAYOUT ..................................................183
SHIFT LOCK CONTROL UNIT INSPECTION

CVT-6
INDEX FOR DTC

INDEX FOR DTCPFP:00024
Alphabetical Index BCS001FM
NOTE:
If DTC “U1000 CAN COMM CIRCUIT” is displayed with other DTC s, first perform the trouble diagnosis
for “DTC U1000 CAN COMMUNICATION LINE”. Refer to CVT-53
.
Items
(CONSULT-II screen terms) DTC Reference page
A/T TCC S/V FNCTN P0744 CVT-94
ATF TEMP SEN/CIRC P0710CVT-69
BELT DAMGP0730CVT-87
BRAKE SW/CIRC P0703CVT-60
CAN COMM CIRCUIT U1000CVT-53
CVT SPD SEN/FNCTN P1723CVT-143
ENGINE SPEED SIG P0725CVT-85
ELEC TH CONTROL P1726CVT-145
ESTM VEH SPD SIG P1722CVT-141
INPUT SPD SEN/CIRC P0715CVT-74
L/PRESS CONTROL P1745CVT-152
L/PRESS SOL/CIRC P0745CVT-97
LU-SLCT SOL/CIRC P1740CVT-147
MANUAL MODE SWITCH P0826CVT-113
PNP SW/CIRCP0705CVT-62
PRESS SEN/FNCTN P0841CVT-123
PRS CNT SOL/A FCTN P0746CVT-102
PRS CNT SOL/B CIRC P0778CVT-108
PRS CNT SOL/B FCTN P0776CVT-105
SEC/PRESS DOWN P0868CVT-131
STARTER RELAY/CIRC P0615CVT-56
STEP MOTR CIRC P1777CVT-153
STEP MOTR/FNCTN P1778CVT-157
TCC SOLENOID/CIRC P0740CVT-89
TCM-POWER SUPPLY P1701CVT-134
TP SEN/CIRC A/T P1705CVT-139
TR PRS SENS/A CIRC P0840CVT-118
TR PRS SENS/B CIRC P0845CVT-126
VEH SPD SEN/CIR AT P0720CVT-79

INDEX FOR DTC
CVT-7
D
E
F
G
H
I
J
K
L
MA
B
CVT

DTC No. Index BCS001FN
NOTE:
If DTC “U1000 CAN COMM CIRCUIT” is displayed with other DTC s, first perform the trouble diagnosis
for “DTC U1000 CAN COMMUNICATION LINE”. Refer to CVT-53
.
DTCItems
(CONSULT-II screen terms)Reference page
P0615 STARTER RELAY/CIRCCVT-56
P0703 BRAKE SW/CIRCCVT-60
P0705 PNP SW/CIRCCVT-62
P0710 ATF TEMP SEN/CIRCCVT-69
P0715 INPUT SPD SEN/CIRCCVT-74
P0720 VEH SPD SEN/CIR ATCVT-79
P0725 ENGINE SPEED SIGCVT-85
P0730 BELT DAMGCVT-87
P0740 TCC SOLENOID/CIRCCVT-89
P0744 A/T TCC S/V FNCTNCVT-94
P0745 L/PRESS SOL/CIRCCVT-97
P0746 PRS CNT SOL/A FCTNCVT-102
P0776 PRS CNT SOL/B FCTNCVT-105
P0778 PRS CNT SOL/B CIRCCVT-108
P0826 MANUAL MODE SWITCHCVT-113
P0840 TR PRS SENS/A CIRCCVT-118
P0841 PRESS SEN/FNCTNCVT-123
P0845 TR PRS SENS/B CIRCCVT-126
P0868 SEC/PRESS DOWNCVT-131
P1701 TCM-POWER SUPPLYCVT-134
P1705 TP SEN/CIRC A/TCVT-139
P1722 ESTM VEH SPD SIGCVT-141
P1723 CVT SPD SEN/FNCTNCVT-143
P1726 ELEC TH CONTROLCVT-145
P1740 LU-SLCT SOL/CIRCCVT-147
P1745 L/PRESS CONTROLCVT-152
P1777 STEP MOTR CIRCCVT-153
P1778 STEP MOTR/FNCTNCVT-157
U1000 CAN COMM CIRCUITCVT-53

CVT-18
CVT SYSTEM

TCM FunctionBCS001G2
The function of the TCM is to:

Receive input signals sent from various switches and sensors.

Determine required line pressure, shifting point, and lock-up operation.

Send required output signals to the step motor and the respective solenoids.
CONTROL SYSTEM OUTLINE
The CVT senses vehicle operating conditions through various sensors. It always controls the optimum shift
position and reduces shifting and lock-up shocks.
CONTROL SYSTEM DIAGRAM
SENSORS (or SIGNAL)

TCM

ACTUATORS
PNP switch
Accelerator pedal position signal
Closed throttle position signal
Engine speed signal
CVT fluid temperature sensor
Vehicle speed signal
Manual mode signal
Stop lamp switch signal
Primary speed sensor
Secondary speed sensor
Primary pressure sensor
Secondary pressure sensorShift control
Line pressure control
Primary pressure control
Secondary pressure control
Lock-up control
Engine brake control
Vehicle speed control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
Duet-EA control
CAN systemSte p mo tor
Torque converter clutch solenoid
valve
Lock-up select solenoid valve
Line pressure solenoid valve
Secondary pressure solenoid
valve
Manual mode indicator
Shift position indicator
CVT indicator lamp
Starter relay
SCIA7872E

CVT SYSTEM
CVT-19
D
E
F
G
H
I
J
K
L
MA
B
CVT

CAN CommunicationBCS001G3
SYSTEM DESCRIPTION
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only. For details, refer to LAN-49,
"CAN System Specification Chart" .
Input/Output Signal of TCMBCS001G4
*1: Input by CAN communications.
*2: If these input and output signals are different, the TCM triggers the fail-safe function. Control item Fluid
pressure
control Select
control Shift con-
trol Lock-up
control CAN com-
munication
control Fail-safe
function
(*2)
Input PNP switch XXXXXX
Accelerator pedal position signal
(*1)XXXXXX
Closed throttle position signal
(*1)XXXX
Engine speed signal
(*1)XX XXX
CVT fluid temperature sensor X X X X X
Manual mode signal
(*1)XXXXX
Stop lamp switch signal
(*1)XXXX
Primary speed sensor X X X X X
Secondary speed sensor X X X X X X
Primary pressure sensor X X
Secondary pressure sensor X X X
TCM power supply voltage signal X X X X X X
Out-
put Step motor X X
TCC solenoid valve X X X
Lock-up select solenoid valve X X X
Line pressure solenoid valve X X X X
Secondary pressure solenoid valve X X X

CVT-20
CVT SYSTEM

Line Pressure and Secondary Pressure ControlBCS001G5

When an input torque signal equivalent to the engine drive force is sent from the ECM to the TCM, the
TCM controls the line pressure solenoid valve and secondary pressure solenoid valve.

This line pressure solenoid controls the pressure regulator valve as the signal pressure and adjusts the
pressure of the operating oil discharged from the oil pump to the line pressure most appropriate to the
driving state. Secondary pressure is controlled by decreasing line pressure.
NORMAL CONTROL
Optimize the line pressure and secondary pressure, depending on driving conditions, on the basis of the throt-
tle position, the engine speed, the primary pulley (input) revolution speed, the secondary pulley (output) revo-
lution speed, the brake signal, the PNP switch signal, the lock-up signal, the voltage, the target gear ratio, the
fluid temperature, and the fluid pressure.
FEEDBACK CONTROL
When controlling the normal fluid pressure or the selected fluid pressure, the secondary pressure can be set
more accurately by using the fluid pressure sensor to detect the secondary pressure and controlling the feed-
back.
Shift ControlBCS001G6
In order to select the gear ratio which can obtain the driving force in accordance with driver's intention and the
vehicle condition, TCM monitors the driving conditions, such as the vehicle speed and the throttle position and
selects the optimum gear ratio, and determines the gear change steps to the gear ratio. Then send the com-
mand to the step motor, and control the flow-in/flow-out of line pressure from the primary pulley to determine
the position of the moving-pulley and control the gear ratio.
SCIA1846E
SCIA6581E

CVT SYSTEM
CVT-21
D
E
F
G
H
I
J
K
L
MA
B
CVT

NOTE:
The gear ratio is set for every position separately.
“D” POSITION
Shifting over all the ranges of gear ratios from the lowest to the high-
est.
“M” POSITION
When the selector lever is put in the manual shift gate side, the fixed
changing gear line is set. By moving the selector lever to + side or -
side, the manual mode switch is changed over, and shift change like
M/T becomes possible following the changing gear set line step by
step.
DOWNHILL ENGINE BRAKE CONTROL (AUTO ENGINE BRAKE CONTROL)
When downhill is detected with the accelerator pedal released, the engine brake will be strengthened up by
downshifting so as not to accelerate the vehicle more than necessary.
ACCELERATION CONTROL
According to vehicle speed and a change of accelerator pedal angle, driver's request for acceleration and driv-
ing scene are judged. This function assists improvement in acceleration feeling by making the engine speed
proportionate to the vehicle speed. And a shift map which can gain a larger driving force is available for com-
patibility of mileage with drivability.
Lock-up and Select ControlBCS001G7

The torque converter clutch piston in the torque converter is engaged to eliminate torque converter slip to
increase power transmission efficiency.

The torque converter clutch control valve operation is controlled by the torque converter clutch solenoid
valve, which is controlled by a signal from TCM. The torque converter clutch control valve engages or
releases the torque converter clutch piston.

When shifting between “N” (“P”) ⇔ “D” (“R”), torque converter clutch solenoid controls engagement power
of forward clutch and reverse brake.

The lock-up applied gear range was expanded by locking up the
torque converter at a lower vehicle speed than conventional
CVT models.
SCIA1953E
SCIA4582E
SCIA1958E

CVT-22
CVT SYSTEM

TORQUE CONVERTER CLUTCH AND SELECT CONTROL VALVE CONTROL
Lock-up and Select Control System Diagram
Lock-up Released
In the lock-up released state, the torque converter clutch control valve is set into the unlocked state by the
torque converter clutch solenoid and the lock-up apply pressure is drained.
In this way, the torque converter clutch piston is not coupled.
Lock-up Applied
In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the torque
converter clutch solenoid and lock-up apply pressure is generated.
In this way, the torque converter clutch piston is pressed and coupled.
Select Control
When shifting between “N” (“P”) ⇔ “D” (“R”), optimize the operating pressure on the basis of the throttle posi-
tion, the engine speed, and the secondary pulley (output) revolution speed to lessen the shift shock.
SCIA2374E

CVT-24
TROUBLE DIAGNOSIS

TROUBLE DIAGNOSISPFP:00004
DTC Inspection Priority ChartBCS001GE
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
If DTC “U1000 CAN COMM CIRCUIT” is displayed with other DTCs, first perform the trouble diagnosis
for “DTC U1000 CAN COMMUNICATION LINE”. Refer to CVT-53
.
Fail-safeBCS001GF
The TCM has an electrical fail-safe mode. This mode makes it possible to operate even if there is an error in a
main electronic control input/output signal circuit.
FAIL-SAFE FUNCTION
If any malfunction occurs in a sensor or solenoid, this function controls the CVT to make driving possible.
Output Speed Sensor (Secondary Speed Sensor)
The shift pattern is changed in accordance with throttle position when an unexpected signal is sent from the
output speed sensor (secondary speed sensor) to the TCM. The manual mode position and second position is
inhibited, and the transaxle is put in “D”.
Input Speed Sensor (Primary Speed Sensor)
The shift pattern is changed in accordance with throttle position and secondary speed (vehicle speed) when
an unexpected signal is sent from the input speed sensor (primary speed sensor) to the TCM. The manual
mode position and second position is inhibited, and the transaxle is put in “D”.
PNP Switch
If an unexpected signal is sent from the PNP switch to the TCM, the transaxle is put in “D”.
Manual Mode Switch
If an unexpected signal is sent from the manual mode switch to the TCM, the transaxle is put in “D”.
CVT Fluid Temperature Sensor
If an unexpected signal is sent from the CVT fluid temperature sensor to the TCM, the gear ratio in use before
receiving the unexpected signal is maintained or the gear ratio is controlled to keep engine speed under 5,000
rpm.
Transmission Fluid Pressure Sensor A (Secondary Pressure Sensor)

If an unexpected signal is sent from the transmission fluid pressure sensor A (secondary pressure sensor)
to the TCM, the secondary pressure feedback control is stopped and the offset value obtained before the
non-standard condition occurs is used to control line pressure.

If transmission fluid pressure sensor A (secondary pressure sensor) error signal is input to TCM, second-
ary pressure feedback control stops, but line pressure is controlled normally.
Pressure Control Solenoid A (Line Pressure Solenoid)
If an unexpected signal is sent from the solenoid to the TCM, the pressure control solenoid A (line pressure
solenoid) is turned OFF to achieve the maximum fluid pressure.
Pressure Control Solenoid B (Secondary Pressure Solenoid)
If an unexpected signal is sent from the solenoid to the TCM, the pressure control solenoid B (secondary pres-
sure solenoid) is turned OFF to achieve the maximum fluid pressure.
Torque Converter Clutch Solenoid
If an unexpected signal is sent from the solenoid to the TCM, the torque converter clutch solenoid is turned
OFF to cancel the lock-up.
Priority Detected items (DTC)
1 U1000 CAN communication line
2 Except above

TROUBLE DIAGNOSIS
CVT-25
D
E
F
G
H
I
J
K
L
MA
B
CVT

Step Motor
If an unexpected signal is sent from the step motor to the TCM, the step motor coil phases “A” through “D” are
all turned OFF to hold the gear ratio used right before the non-standard condition occurred.
CVT Lock-up Select Solenoid
If an unexpected signal is sent from the solenoid to the TCM, the CVT lock-up select solenoid is turned OFF to
cancel the lock-up.
TCM Power Supply (Memory Back-up)
Transaxle assembly is protected by limiting the engine torque when the memory back-up power supply (for
controlling) from the battery is not supplied to TCM. Normal statues is restored when turning the ignition switch
OFF to ON after the normal power supply.
How to Perform Trouble Diagnosis for Quick and Accurate RepairBCS001GG
INTRODUCTION
The TCM receives a signal from the vehicle speed sensor, PNP
switch and provides shift control or lock-up control via CVT solenoid
valves.
Input and output signals must always be correct and stable in the
operation of the CVT system. The CVT system must be in good
operating condition and be free of valve seizure, solenoid valve mal-
function, etc.
It is much more difficult to diagnose an error that occurs intermit-
tently rather than continuously. Most intermittent errors are caused
by poor electric connections or improper wiring. In this case, careful
checking of suspected circuits may help prevent the replacement of
good parts.
A visual check only may not find the cause of the errors. A road test
with CONSULT-II or a circuit tester connected should be performed.
Follow the CVT-26, "
WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such errors, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “DIAGNOSTIC WORKSHEET” as
shown on the example (Refer to CVT-27
) should be used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot driveability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
SAT631IB
SAT632I
SEF234G