
CVT-26
< SERVICE INFORMATION >
ON BOARD DIAGNOSTIC (OBD) SYSTEM
ON BOARD DIAGNOSTIC (OBD) SYSTEM
IntroductionINFOID:0000000001703446
The CVT system has two self-diagnostic systems.
The first is the emission-related on board diagnostic system (OBD-II) performed by the TCM in combination
with the ECM. The malfunction is indicated by the MIL (malfunction indicator lamp) and is stored as a DTC in
the ECM memory, and the TCM memory.
The second is the TCM original self-diagnosis performed by the TCM. The malfunction is stored in the TCM
memory. The detected items are overlapped with OBD-II self-diagnostic items. For detail, refer to CVT-47,
"CONSULT-III Function (TRANSMISSION)".
OBD-II Function for CVT SystemINFOID:0000000001703447
The ECM provides emission-related on board diagnostic (OBD-II) functions for the CVT system. One function
is to receive a signal from the TCM used with OBD-related parts of the CVT system. The signal is sent to the
ECM when a malfunction occurs in the corresponding OBD-related part. The other function is to indicate a
diagnostic result by means of the MIL (malfunction indicator lamp) on the instrument panel. Sensors, switches
and solenoid valves are used as sensing elements.
The MIL automatically illuminates in One or Two Trip Detection Logic when a malfunction is sensed in relation
to CVT system parts.
One or Two Trip Detection Logic of OBD-IIINFOID:0000000001703448
ONE TRIP DETECTION LOGIC
If a malfunction is sensed during the first test drive, the MIL will illuminate and the malfunction will be stored in
the ECM memory as a DTC. The TCM is not provided with such a memory function.
TWO TRIP DETECTION LOGIC
When a malfunction is sensed during the first test drive, it is stored in the ECM memory as a 1st trip DTC
(diagnostic trouble code) or 1st trip freeze frame data. At this point, the MIL will not illuminate. — 1st trip
If the same malfunction as that experienced during the first test drive is sensed during the second test drive,
the MIL will illuminate. — 2nd trip
The “trip” in the “One or Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation.
OBD-II Diagnostic Trouble Code (DTC)INFOID:0000000001703449
HOW TO READ DTC AND 1ST TRIP DTC
DTC and 1st trip DTC can be read by the following methods.
(  with CONSULT-III or   GST) CONSULT-III or GST (Generic Scan Tool) Examples: P0705, P0720 etc.
These DTC are prescribed by SAE J2012.
(CONSULT-III also displays the malfunctioning component or system.)
•1st trip DTC No. is the same as DTC No.
•Output of the diagnostic trouble code indicates that the indicated circuit has a malfunction. How-
ever, in case of the Mode II and GST, they do not indicate whether the malfunction is still occurring or
occurred in the past and returned to normal.
CONSULT-III can identify them as shown below, therefore, CONSULT-III (if available) is recom-
mended.
DTC or 1st trip DTC of a malfunction is displayed in SELF-DIAGNOSTIC RESULTS mode for “ENGINE” with
CONSULT-III. Time data indicates how many times the vehicle was driven after the last detection of a DTC.
If the DTC is being detected currently, the time data will be “0”.
If a 1st trip DTC is stored in the ECM, the time data will be “1t”.
Freeze Frame Data and 1st Trip Freeze Frame Data 

ON BOARD DIAGNOSTIC (OBD) SYSTEM
CVT-27
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The ECM has a memory function, which stores the driving condition such as fuel system status, calculated
load value, engine coolant temperature, short term fuel trim, long term fuel trim, engine speed and vehicle
speed at the moment the ECM detects a malfunction.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data,
and the data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-III
or GST. The 1st trip freeze frame data can only be displayed on the CONSULT-III screen, not on the GST. For
details, refer to EC-109, "
CONSULT-II Function (ENGINE)".
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data, and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
Both 1st trip freeze frame data and freeze frame data (along with the DTC) are cleared when the ECM mem-
ory is erased.
HOW TO ERASE DTC
The diagnostic trouble code can be erased by CONSULT-III, GST or ECM DIAGNOSTIC TEST MODE as
described following.
•If the battery cable is disconnected, the diagnostic trouble code will be lost within 24 hours.
•When you erase the DTC, using CONSULT-III or GST is easier and quicker than switching the mode
selector on the ECM.
The following emission-related diagnostic information is cleared from the ECM memory when erasing DTC
related to OBD-II. For details, refer to EC-47, "
Emission-related Diagnostic Information".
•Diagnostic trouble codes (DTC)
•1st trip diagnostic trouble codes (1st trip DTC)
•Freeze frame data
•1st trip freeze frame data
•System readiness test (SRT) codes
•Test values
 HOW TO ERASE DTC (WITH CONSULT-III)
•If a DTC is displayed for both ECM and TCM, it is necessary to be erased for both ECM and TCM.
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.
2. Turn CONSULT-III ON and touch “TRANSMISSION”.
3. Touch “SELF-DIAG RESULTS”.
4. Touch “ERASE”. (The DTC in the TCM will be erased.) Then touch “BACK” twice.
5. Touch “ENGINE”.
6. Touch “SELF-DIAG RESULTS”.
7. Touch “ERASE”. (The DTC in the ECM will be erased.)
 HOW TO ERASE DTC (WITH GST)
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.
2. Select Mode 4 with GST (Generic Scan Tool). For details, refer to EC-119, "
Generic Scan Tool (GST)
Function".
Malfunction Indicator Lamp (MIL)INFOID:0000000001703450
DESCRIPTION 
Priority Items
1
Freeze frame dataMisfire — DTC: P0300 - P0306
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes CVT related items)
3 1st trip freeze frame data 

TROUBLE DIAGNOSIS
CVT-29
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TROUBLE DIAGNOSIS
DTC Inspection Priority ChartINFOID:0000000001703451
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-56
 .
Fail-SafeINFOID:0000000001703452
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 overdrive-off mode is inhibited, and the tran-
saxle 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 sport mode
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”. 
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 3500
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, secondary
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.
Ste p M oto r
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
Priority Detected items (DTC)
1 U1000 CAN communication line
2 Except above 

TROUBLE DIAGNOSIS
CVT-41
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• Before road test, familiarize yourself with all test procedures and
items to check.
• Perform tests on all items until specified symptom is found. Trou-
bleshoot items which check out No Good after road test. 
CONSULT-III START PROCEDURE
• Using CONSULT-III, perform a cruise test and record the result.
• Print the result and ensure that shifts and lock-ups take place as per Shift Schedule.
1. Touch “DATA MONITOR” on “SELECT DIAG MODE” screen.
2. Touch “MAIN SIGNALS” to set recording condition.
3. See “Numerical Display”, “Barchart Display” or “Line Graph Display”.
4. Touch “START”.
5. When performing cruise test. Refer to CVT-43, "
Cruise Test" .
6. After finishing cruise test part, touch “RECORD”.
7. Touch “STORE”.
8. Touch “BACK”.
9. Touch “DISPLAY”.
10. Touch “PRINT”.
11. Check the monitor data printed out.
Check before Engine Is StartedINFOID:0000000001703458
1.CHECK O/D OFF INDICATOR LAMP
1. Park vehicle on flat surface.
2. Move selector lever to “P” position.
3. Turn ignition switch OFF. Wait at least 5 seconds.
4. Turn ignition switch ON. (Do not start engine.)
Does O/D OFF indicator lamp come on for about 2 seconds?
YES >> 1. Turn ignition switch OFF.
2. Perform self-diagnosis and note NG items.
Refer to CVT-47, "
CONSULT-III Function (TRANSMISSION)" .
3. Go to CVT-41, "
Check at Idle" .
NO >> Stop “Road Test”. Go to CVT-151, "
O/D OFF Indicator Lamp Does Not Come On" .
Check at IdleINFOID:0000000001703459
1.CHECK STARTING THE ENGINE
1. Park vehicle on flat surface.
2. Move selector lever to “P” or “N” position.
3. Turn ignition switch OFF.
4. Turn ignition switch START.
Is engine started?
SAT496G 

TROUBLE DIAGNOSIS
CVT-45
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9.CHECK ENGINE BRAKE FUNCTION — PART 3
1. Move selector lever to “L” position.
2. Check engine brake.
Does engine braking effectively reduce speed in 
“L” position?
YES >> 1. Stop the vehicle.
2. Perform self-diagnosis. Refer to CVT-47, "
CONSULT-III Function (TRANSMISSION)" .
NO >> Mark the box of CVT-159, "
Vehicle Does Not Decelerate by Engine Brake"  on the CVT-30, "How
to Perform Trouble Diagnosis for Quick and Accurate Repair" . Then continue trouble diagnosis.
Vehicle Speed When Shifting GearsINFOID:0000000001703461
Numerical value data are reference values.
CAUTION:
Lock-up clutch is engaged when vehicle speed is approximately 18 km/h (11 MPH) to 90 km/h (56 MPH).
TCM Terminal and Reference ValueINFOID:0000000001703462
TCM HARNESS CONNECTOR TERMINAL LAYOUT 
TERMINALS AND REFERENCE VALUES FOR TCM
Data are reference values and are measured between each terminal and ground.
Engine type  Throttle position Shift patternEngine speed (rpm)
At 40 km/h (25 MPH) At 60 km/h (37 MPH)
MR18DE8/8“D” position
Overdrive-off mode
“L” position3,600 - 4,500 4,400 - 5,300
2/8“D” position 1,300 - 3,100 1,400 - 3,500
Overdrive-off mode 2,200 - 3,000 2,800 - 3,600
“L” position 3,200 - 4,100 3,900 - 4,800
WCIA0717E
Te r m i n a lWire 
colorItem Condition Data (Approx.)
1GRPressure control 
solenoid valve A 
(Line pressure 
solenoid valve)
and Release your foot from the accelerator pedal. 5.0 - 7.0 V
 Press the accelerator pedal all the way down. 1.0 - 3.0 V
2LGPressure control 
solenoid valve B 
(Secondary 
pressure sole-
noid valve) Release your foot from the accelerator pedal. 5.0 - 7.0 V
 Press the accelerator pedal all the way down. 3.0 - 4.0 V
3SBTorque converter 
clutch solenoid 
valveWhen vehi-
cle cruises in 
“D” position.When CVT performs lock-up. 6.0 V
When CVT does not perform lock-up. 1.0 V 

TROUBLE DIAGNOSIS
CVT-47
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CONSULT-III Function (TRANSMISSION)INFOID:0000000001703463
CONSULT-III can display each diagnostic item using the diagnostic test modes shown below.
FUNCTION
32 YPNP switch 3 
(monitor)Selector lever in “D” and “L” positions. 0 V
Selector lever in “P”, “R” and “N” positions.8.0 V - Battery 
voltage
34 SB PNP switch 2Selector lever in “N”, “D” and “L” positions. 0 V
Selector lever in “P” and “R” positions.10.0 V - Battery 
voltage
35 W PNP switch 3Selector lever in “D” and “L” positions. 0 V
Selector lever in “P”, “R” and “N” positions.8.0 V - Battery 
voltage
36 W PNP switch 4Selector lever in “R” and “D” positions. 0 V
Selector lever in “P”, “N” and “L” positions.10.0 V - Battery 
voltage
37 LTransmission 
fluid pressure 
sensor A (Sec-
ondary pressure 
sensor)and “N” position idle 1.0 V
38 VInput speed sen-
sor (Primary 
speed sensor)When driving [“L” position, 20 km/h (12 MPH)]. 1000 Hz
41 GTransmission 
fluid pressure 
sensor B (Prima-
ry pressure sen-
sor)and “N” position idle  0.7 V
42 LG Sensor ground Always  0 V
46 O Sensor power— 5.0 V
— 0 V
47 GCVT fluid tem-
perature sensor When CVT fluid temperature is 20°C (68°F)  2.0 V
When CVT fluid temperature is 80°C (176°F)  1.0 V
48 B Ground Always  0 V Te r m i n a lWire 
colorItem Condition Data (Approx.)
Diagnostic test mode Function
Work supportThis mode enables a technician to adjust some devices faster and more accurately by following the in-
dications on CONSULT-III.
Self-diagnostic results Self-diagnostic results can be read and erased quickly.
Data monitor Input/Output data in the TCM can be read. 
![NISSAN TIIDA 2008  Service Repair Manual TROUBLE DIAGNOSIS
CVT-51
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PVEH SPD SEN/
CIR AT• Signal from vehicle speed sensor CVT [Output speed sen-
sor (Secondary speed sensor)] not input  NISSAN TIIDA 2008  Service Repair Manual TROUBLE DIAGNOSIS
CVT-51
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PVEH SPD SEN/
CIR AT• Signal from vehicle speed sensor CVT [Output speed sen-
sor (Secondary speed sensor)] not input](/manual-img/5/57399/w960_57399-889.png)
TROUBLE DIAGNOSIS
CVT-51
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PVEH SPD SEN/
CIR AT• Signal from vehicle speed sensor CVT [Output speed sen-
sor (Secondary speed sensor)] not input due to open or 
short circuit
• Unexpected signal input during runningP0720 P0720CVT-80
ENGINE SPEED 
SIG• TCM does not receive the CAN communication signal from 
the ECM
• Engine speed is too low while drivingP0725 —CVT-85
BELT DAMG Unexpected gear ratio detected P0730 —CVT-87
TCC SOLENOID/
CIRCNormal voltage not applied to solenoid due to open or short 
circuitP0740 P0740CVT-88
A/T TCC S/V 
FNCTN• CVT cannot perform lock-up even if electrical circuit is good
• TCM detects as irregular by comparing difference value 
with slip rotation
• There is big difference engine speed and primary speed 
when TCM lock-up signal is onP0744 P0744CVT-93
L/PRESS SOL/
CIRC• Normal voltage not applied to solenoid due to open or short 
circuit
• TCM detects as irregular by comparing target value with 
monitor valueP0745 P0745CVT-95
PRS CNT SOL/A 
FCTNUnexpected gear ratio was detected in the LOW side due to 
excessively low line pressureP0746 P0746CVT-100
PRS CNT SOL/B 
FCTNSecondary pressure is too high or too low compared with the 
commanded value while drivingP0776 P0776CVT-102
PRS CNT SOL/B 
CIRC• Normal voltage not applied to solenoid due to cut line, 
short, or the like
• TCM detects as irregular by comparing target value with 
monitor valueP0778 P0778CVT-104
TR PRS SENS/A 
CIRCSignal voltage of the transmission fluid pressure sensor A 
(secondary pressure sensor) is too high or too low while driv-
ingP0840 P0840CVT-109
PRESS SEN/
FNCTNCorrelation between the values of the transmission fluid pres-
sure sensor A (secondary pressure sensor) and the transmis-
sion fluid pressure sensor B (primary pressure sensor) is out 
of specificationP0841 —CVT-113
TR PRS SENS/B 
CIRCSignal voltage of the transmission fluid pressure sensor B 
(primary pressure sensor) is too high or too low while drivingP0845 P0845CVT-115
SEC/PRESS 
DOWNSecondary fluid pressure is too low compared with the com-
manded value while drivingP0868 —CVT-119
TCM-POWER 
SUPPLY• When the power supply to the TCM is cut OFF, for example 
because the battery is removed, and the self-diagnosis 
memory function stops
• This is not a malfunction message (Whenever shutting 
OFF a power supply to the TCM, this message appears on 
the screen)P1701 —CVT-121
TP SEN/CIRC A/TTCM does not receive the proper accelerator pedal position 
signals (input by CAN communication) from ECMP1705 —CVT-125
ESTM VEH SPD 
SIG*2• CAN communication with the ABS actuator and the electric 
unit (control unit) is malfunctioning
• There is a great difference between the vehicle speed sig-
nal from the ABS actuator and the electric unit (control 
unit), and the vehicle speed sensor signalP1722 —CVT-127
Items (CONSULT-
III screen terms)Malfunction is detected when...TCM self-di-
agnosisOBD-III (DTC)
Reference 
page “TRANSMIS-
SION” with 
CONSULT-IIIMIL indicator 
lamp*1, “EN-
GINE” with 
CONSULT-III 
or GST 

CVT-56
< SERVICE INFORMATION >
DTC U1000 CAN COMMUNICATION LINE
DTC U1000 CAN COMMUNICATION LINE
DescriptionINFOID:0000000001703465
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 malfunction detection ability.
Many electronic 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 con-
nected 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.
On Board Diagnosis LogicINFOID:0000000001703466
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “U1000 CAN COMM CIRCUIT” with CONSULT-III is detected when TCM cannot
communicate to other control units.
Possible CauseINFOID:0000000001703467
Harness or connectors
(CAN communication line is open or shorted.)
DTC Confirmation ProcedureINFOID:0000000001703468
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, touch “ERASE” on “SELF-DIAG RESULTS” and then perform the following procedure to con-
firm the malfunction is eliminated.
 WITH CONSULT-III
1. Turn ignition switch ON. (Do not start engine.)
2. Select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Start engine and wait for at least 6 seconds.
4. If DTC is detected, go to CVT-58, "
Diagnosis Procedure" .
 WITH GST
Follow the procedure “WITH CONSULT-III”.