1999 NISSAN PRIMERA engine

DescriptionNCAT0232IThe CVT fluid pressure sensor detects line pressure of CVT,
and sends TCM the signal.
CONSULT-II REFERENCE VALUE IN DATA MONITOR
MODE
NCAT0232S01Remarks: Specification data are reference values.
Monitor item Condition Specification
CVT fluid pressure sensorThrottle valve fully closed (PL Duty: 4%)
"
Throttle valve fully depressed
(PL Duty: 94%)Approx. 1.0 V
"
Approx. 4.0 V
TCM TERMINALS AND REFERENCE VALUENCAT0232S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
37 W/G
CVT fluid pressure
sensor
When engine runs at idle speed.Approx. 1.0 V
When engine runs at stall speed.Approx. 4.0V
42 B
ÐÐ
46 P/LÐ4.5 - 5.5 V
ON BOARD DIAGNOSIS LOGICNCAT0232S03
Diagnostic trouble code Malfunction is detected when ... Check items (Possible cause)
: LINE PRESS SEN
TCM receives an excessively low or high
voltage from the step motor.IHarness or connectors
(The sensor circuit is open or shorted.)
ICVT fluid pressure sensor
: P1791
: MI Code No. 1791
DTC P1791 CVT FLUID PRESSURE SENSOR
Description
AT-94

DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NCAT0232S04CAUTION:
IAlways drive vehicle at a safe speed.
IBe careful not to rev engine into the red zone on the
tachometer.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for ªCVTº with CONSULT-II.
2) Make sure that output voltage of CVT fluid temperature sne-
sor is within the range below.
FLUID TEMP SEN: 0.5 - 1.5V
If out of range, drive the vehicle to decrease the voltage
(warm up the fluid) or stop engine to increase the voltage
(cool down the fluid)
3) Select ªDATA MONITORº mode for ªENGINEº with CONSULT-
II.
4) Start engine and maintain the following conditions for at least
5 consecutive seconds.
VHCL SPEED SE: 10 km/h (6 MPH) or more
THRTL POS SEN: 1.3V
Selector lever: D position
ENG SPEED: 450 rpm or more
If the check result is NG, go to ªDiagnostic Procedureº, AT-97.
With GST
Follow the procedure ªWith CONSULT-IIº.
SAT651J
SAT971J
SAT654J
DTC P1791 CVT FLUID PRESSURE SENSOR
Description (Cont'd)
AT-95

Diagnostic ProcedureNCAT0234
1 CHECK PRESSURE SENSOR
Refer to ªComponent Inspectionº, AT-98.
OK or NG
OK (With CONSULT-II)©GO TO 2.
OK (Without CONSULT-II)©GO TO 3.
NG©Repair or replace pressure sensor.
2 CHECK INPUT SIGNAL (With CONSULT-II)
With CONSULT-II
1. Start engine.
2. Select ªECU Input Item Parameter Listº in ªDATA MONITORº mode for ªCVTº with CONSULT-II.
3. Read out the value of ªLINE PRES SENº while driving.
IThrottle valve fully closed (PL Duty: 4%): Approx. 1.0V
IThrottle valve fully depressed (PL Duty: 94%): Approx. 4.0V
OK or NG
OK©GO TO 4.
NG©Check the following items:
IHarness for short or open between TCM, ECM and CVT fluid pressure sensor (Main
harness)
IGround circuit for ECM
Refer to EC section (ªTROUBLE DIAGNOSIS FOR POWER SUPPLYº).
3 CHECK INPUT SIGNAL (Without CONSULT-II)
Without CONSULT-II
Refer to ªComponent Inspectionº, AT-98.
OK or NG
OK©GO TO 4.
NG©Check the following items:
IHarness for short or open between TCM, ECM and CVT fluid pressure sensor (Main
harness).
IGround circuit for ECM
Refer to EC section (ªTROUBLE DIAGNOSIS FOR POWER SUPPLYº).
4 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-95.
OK or NG
OK©INSPECTION END
NG©1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness con-
nector.
DTC P1791 CVT FLUID PRESSURE SENSOR
Diagnostic Procedure
AT-97

Component Inspection=NCAT0235CVT FLUID PRESSURE SENSORNCAT0235S01IStart engine.
ICheck voltage between terminals 1 and 6, 6 and 10.
Terminal No. Voltage
16Approx. 0.5 - 4.5V
610Approx. 4.5 - 5.5V
SAT691J CVT fluid pressure sensor connector
DTC P1791 CVT FLUID PRESSURE SENSOR
Component Inspection
AT-98

Description
ªCVT SAFE FUNCTIONº is function to protect CVT.
ON BOARD DIAGNOSIS LOGIC
Diagnostic trouble code Malfunction is detected when ... Check items (Possible cause)
: CVT SAFE FUNCTION
TCM is malfunctioning TCM
: 10th judgement flicker
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for CVT with CONSULT-II.
2) Start engine.
3) Run engine for at least 2 seconds at idle speed.
Without CONSULT-II
1) Start engine.
2) Perform self-diagnosis. Refer to SELF-DIAGNOSTIC PROCE-
DURE (Without CONSULT-II), AT-25.SAT651J
SAT971J
SAT455FALight
Shade
CVT SAFE FUNCTION
Description
AT-99

DescriptionNCAT0239The TCM consists of a microcomputer and connectors for signal
input and output and for power supply. The unit controls the CVT.
ON BOARD DIAGNOSIS LOGICNCAT0239S01
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: CONTROL UNIT (RAM)
: CONTROL UNIT (ROM)TCM memory (RAM) or (ROM) is mal-
functioning.TCM
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NCAT0239S02NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for CVT with CONSULT-II.
2) Start engine.
3) Run engine for at least 2 seconds at idle speed.
SAT574J
SAT651J
SAT971J
CONTROL UNIT (RAM), CONTROL UNIT (ROM)
Description
AT-101

DescriptionNCAT0241The TCM consists of a microcomputer and connectors for signal
input and output and for power supply. The unit controls the CVT.
ON BOARD DIAGNOSIS LOGICNCAT0241S01
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: CONT UNIT (EEPROM)TCM memory (EEPROM) is malfunction-
ing.TCM
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NCAT0241S02NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for CVT with CONSULT-II.
2) Start engine.
3) Run engine for at least 2 seconds at idle speed.
SAT574J
SAT651J
SAT971J
CONTROL UNIT (EEPROM)
Description
AT-103

1 CHECK PNP SWITCH CIRCUIT (With CONSULT-II)
With CONSULT-II
1. Turn ignition switch to ªONº position.
(Do not start engine.)
2. Select ªECU INPUT SIGNALSº in ªDATA MONITORº mode for ªCVTº with CONSULT-II.
SAT651J3. Read out ªP/Nº, ªRº, ªDº and ªLº position switches moving selector lever to each position.
Check the signal of the selector lever position is indicated properly.
OK or NG
OK©GO TO 3.
NG©Check the following items:
IPNP switch
Refer to ªComponent Inspectionº, AT-53.
IHarness for short or open between ignition switch and PNP switch (Main harness)
IHarness for short or open between PNP switch and TCM (Main harness)
IIgnition switch and fuse
Refer to EL section (ªPOWER SUPPLY ROUTINGº).
IDiode (P, N positions)
2 CHECK PNP SWITCH CIRCUIT (Without CONSULT-II)
With CONSULT-II
1. Turn ignition switch to ªONº position.
(Do not start engine.)
2. Check voltage between TCM terminals 27, 34, 35, 36 and ground while moving selector lever through each position.
Voltage:
B: Battery voltage
0: 0V
OK or NG
OK©GO TO 3.
NG©Check the following items:
IPNP switch
Refer to ªComponent Inspectionº, AT-53.
IHarness for short or open between ignition switch and PNP switch (Main harness)
IHarness for short or open between PNP switch and TCM (Main harness)
IIgnition switch and fuse
Refer to EL section (ªPOWER SUPPLY ROUTINGº).
IDiode (P, N positions)
Lever
positionTerminal No.
36 35 34 27
P, NB000
R0B00
D0 0B0
L000B
MTBL0312
TROUBLE DIAGNOSES FOR NON-DETECTABLE ITEMS
PNP Switch, Stop Lamp Switch and Throttle Position Switch (Cont'd)
AT-106