CVT-30
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Revision: June 20062007 Versa
ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
IntroductionUCS005Y0
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-61,
"Display Items List" .
OBD-II Function for CVT SystemUCS005Y1
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-IIUCS005Y2
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)UCS005Y3
HOW TO READ DTC AND 1ST TRIP DTC
DTC and 1st trip DTC can be read by the following methods.
( with CONSULT-II or GST) CONSULT-II or GST (Generic Scan Tool) Examples: P0705, P0720 etc.
These DTC are prescribed by SAE J2012.
(CONSULT-II 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-II can identify them as shown below, therefore, CONSULT-II (if available) is recom-
mended.
A sample of CONSULT-II display for DTC and 1st trip DTC is shown
on the next page. DTC or 1st trip DTC of a malfunction is displayed
in SELF-DIAGNOSTIC RESULTS mode for “ENGINE” with CON-
SULT-II. Time data indicates how many times the vehicle was driven
after the last detection of a DTC.
BCIA0030E
CVT-34
TROUBLE DIAGNOSIS
Revision: June 20062007 Versa
TROUBLE DIAGNOSISPFP:00004
DTC Inspection Priority ChartUCS005Y5
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-68
.
Fail-safeUCS005Y6
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 -S AFE F UN CTI ON
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, 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.
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.
Priority Detected items (DTC)
1 U1000 CAN communication line
2 Except above
TROUBLE DIAGNOSIS
CVT-35
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CVT
Revision: June 20062007 Versa
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 RepairUCS005Y7
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.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used with the OBD-related parts of the
CVT system for malfunction-diagnostic purposes. The TCM is capa-
ble of diagnosing malfunctioning parts while the ECM can store mal-
functions in its memory.
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 GST) or a circuit tester connected should be
performed. Follow the CVT-36, "
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-37
) 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.
SAT6 3 1IB
SAT6 3 2I
SEF 2 34 G
CVT-72
DTC P0615 START SIGNAL CIRCUIT
Revision: June 20062007 Versa
DTC P0615 START SIGNAL CIRCUITPFP:25230
DescriptionUCS005YQ
TCM controls starter relay in IPDM E/R.
TCM switches starter relay ON at “P” or “N” position and allows to crank engine.
Then it prohibits cranking other than at “P” or “N” position.
CONSULT-II Reference ValueUCS005YR
On Board Diagnosis LogicUCS005YS
This is not an OBD-II self-diagnostic item.
Diagnostic trouble code “P0615 STARTER RELAY/CIRC” with CONSULT-II is detected when starter relay
switched ON other than at “P” or “N” position. (or when switched OFF at “P” or “N” position).
Possible CauseUCS005YT
Harness or connectors
(Starter relay and TCM circuit is open or shorted.)
Starter relay
DTC Confirmation ProcedureUCS005YU
CAUTION:
Always drive vehicle at a safe speed.
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-II
1. Turn ignition switch ON. (Do not start engine.)
2. Select “DATA MONITOR” mode for “TRANSMISSION” with
CONSULT-II.
3. Start engine.
4. Drive vehicle for at least 2 consecutive seconds.
5. If DTC is detected, go to CVT-74, "
Diagnostic Procedure" .
Item name Condition Display value
STRTR RLY OUTSelector lever in “P” and “N” positions ON
Selector lever in other positions OFF
STRTR RLY MONSelector lever in “P” and “N” positions ON
Selector lever in other positions OFF
BCIA0031E
CVT-74
DTC P0615 START SIGNAL CIRCUIT
Revision: June 20062007 Versa
TCM terminal data are reference values, measured between each terminal and ground.
Diagnostic ProcedureUCS005YW
1. CHECK STARTER RELAY SIGNAL
With CONSULT-II
1. Turn ignition switch ON. (Do not start engine.)
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode
for “TRANSMISSION” with CONSULT-II and check monitor
“STRTR RLY OUT”, “STRTR RLY MON”(PNP relay) ON/OFF.
Without CONSULT-II
1. Turn ignition switch ON. (Do not start engine.)
2. Check voltage between the TCM connector terminal and
ground.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2. DETECT MALFUNCTIONING ITEM
Check the following:
Starter relay. Refer to PG-73, "STANDARDIZED RELAY" .
Open or short-circuit in the harness between TCM and the starter relay. Refer to CVT-73, "Wiring Diagram
— CVT — STSIG" .
Ground circuit for the starter relay. Refer to SC-12, "Wiring Diagram — START —" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
Te r m i n a lWire
colorItem Condition Data (Approx.)
24 BR Starter relaySelector lever in “N” and “P” positions Battery voltage
Selector lever in other positions 0 V
Item name Condition Display value
STRTR RLY OUTSelector lever in “P” and
“N” positionsON
Selector lever in other
positionsOFF
STRTR RLY MONSelector lever in “P” and
“N” positionsON
Selector lever in other
positionsOFF
Terminal Item Condition Data (Approx.)
24St a r t e r
relaySelector lever in “N” and “P”
positionsBattery voltage
Selector lever in other posi-
tions0 V
SCIA2274E
SCIA2022E
CVT-76
DTC P0703 STOP LAMP SWITCH CIRCUIT
Revision: June 20062007 Versa
DTC P0703 STOP LAMP SWITCH CIRCUITPFP:25320
DescriptionUCS005YX
ON, OFF status of the stop lamp switch is sent via the CAN communication from the combination meter to
TCM using the signal.
CONSULT-II Reference ValueUCS005YY
On Board Diagnosis LogicUCS005YZ
This is not an OBD-II self-diagnostic item.
Diagnostic trouble code “P0703 BRAKE SW/CIRC” with CONSULT-II is detected when the stop lamp
switch does not switch to ON and OFF.
–The stop lamp switch does not switch to ON, OFF.
Possible CauseUCS005Z0
Harness or connectors
(Stop lamp switch, and combination meter circuit are open or shorted.)
(CAN communication line is open or shorted.)
Stop lamp switch
DTC Confirmation ProcedureUCS005Z1
CAUTION:
Always drive vehicle at a safe speed.
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-II
1. Turn ignition switch ON. (Do not start engine.)
2. Select “DATA MONITOR” mode for “TRANSMISSION” with
CONSULT-II.
3. Start engine.
4. Start vehicle for at least 3 consecutive seconds.
5. If DTC is detected, go to CVT-77, "
Diagnostic Procedure" .
Item name Condition Display value
BRAKE SWDepressed brake pedal ON
Released brake pedal OFF
BCIA0031E
DTC P0703 STOP LAMP SWITCH CIRCUIT
CVT-77
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CVT
Revision: June 20062007 Versa
Diagnostic ProcedureUCS005Z2
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis check. Refer to CVT-60, "
SELF-DIAGNOSTIC RESULT MODE" .
Is any malfunction of the
“U1000 CAN COMM CIRCUIT” indicated?
YES >> Check CAN communication line. Refer to CVT-68, "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK STOP LAMP SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch ON. (Do not start engine.)
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“TRANSMISSION” with CONSULT-II.
3. Read out ON/OFF switching action of the “BRAKE SW”.
OK or NG
OK >>INSPECTION END
NG >> GO TO 3.
3. CHECK STOP LAMP SWITCH
Check continuity between stop lamp switch harness connector E13
terminals 1 and 2. Refer to CVT-176, "
Wiring Diagram — CVT —
NONDTC" .
Check stop lamp switch after adjusting brake pedal — refer to
BR-6, "
BRAKE PEDAL" .
OK or NG
OK >> Check the following. If NG, repair or replace damaged
parts.
Harness for short or open between battery and stop lamp switch.
Harness for short or open between stop lamp switch and combination meter.
NG >> Repair or replace the stop lamp switch.
Item name Condition Display value
BRAKE SWDepressed brake pedal ON
Released brake pedal OFF
SCIA2275E
Condition Continuity
When brake pedal is depressed Yes
When brake pedal is released No
SCIA7982E
CVT-78
DTC P0705 PARK/NEUTRAL POSITION SWITCH
Revision: June 20062007 Versa
DTC P0705 PARK/NEUTRAL POSITION SWITCHPFP:32006
DescriptionUCS005Z3
The PNP switch is included in the control valve assembly.
The PNP switch includes 4 transmission position switches.
TCM judges the selector lever position by the PNP switch signal.
CONSULT-II Reference ValueUCS005Z4
On Board Diagnosis LogicUCS005Z5
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “P0705 PNP SW/CIRC” with CONSULT-II is detected under the following condi-
tions.
–When TCM does not receive the correct voltage signal from the PNP switches 1, 2, 3 and 4 based on the
gear position.
–When the signal from monitor terminal of PNP switch 3 is different from PNP switch 3.
Possible CauseUCS005Z6
Harness or connectors
(PNP switches 1, 2, 3, 4 and TCM circuit is open or shorted.)
PNP switches 1, 2, 3, 4
PNP switch 3 monitor terminal is open or shorted
DTC Confirmation ProcedureUCS005Z7
CAUTION:
Always drive vehicle at a safe speed.
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.
Shift position PNP switch 1 PNP switch 2 PNP switch 3 PNP switch 4 PNP switch 3 (monitor)
P OFF OFF OFF OFF OFF
R ON OFF OFF ON OFF
N ON ON OFF OFF OFF
DONONONON ON
L OFF ON ON OFF ON
Item name Condition Display value
INH SW3MSelector lever in “D” and “L” positions ON
Selector lever in “P”, “R” and “N” positions OFF
INH SW4Selector lever in “R” and “D” positions ON
Selector lever in “P”, “N” and “L” positions OFF
INH SW3Selector lever in “D” and “L” positions ON
Selector lever in “P”, “R” and “N” positions OFF
INH SW2Selector lever in “N”, “D” and “L” positions ON
Selector lever in “P” and “R” positions OFF
INH SW1Selector lever in “R”, “N” and “D” positions ON
Selector lever in “P” and “L” positions OFF