2001 INFINITI QX4 transmission

18 ERASE UNNECESSARY DTC
After this inspection, unnecessary DTC No. might be displayed.
Erase the stored memory in ECM and TCM (Transmission control module).
Refer to ªHOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATIONº, EC-72 and AT-35, ªHOW TO ERASE
DTCº.
With CONSULT-II©GO TO 19.
Without CONSULT-II©GO TO 20.
19 CHECK HEATED OXYGEN SENSOR 1 (FRONT) (BANK 2) SIGNAL
With CONSULT-II
1. Run engine at about 2,000 rpm for about 2 minutes under no-load.
2. See ªHO2S1 MNTR (B2)º in ªDATA MONITORº mode.
3. Running engine at 2,000 rpm under no-load (engine is warmed up to normal operating temperature.), check that the
monitor fluctuates between ªLEANº and ªRICHº more than 5 times during 10 seconds.
SEF945Y
OK or NG
OK©GO TO 23.
NG (Monitor does not
fluctuate.)©GO TO 28.
NG (Monitor fluctuates
less than 5 times.)©GO TO 21.
20 CHECK HEATED OXYGEN SENSOR 1 (FRONT) (BANK 2) SIGNAL
Without CONSULT-II
1. Run engine at about 2,000 rpm for about 2 minutes under no-load.
2. Set voltmeter probe between ECM terminal 62 and ground.
3. Make sure that the voltage fluctuates between 0 - 0.3V and 0.6 - 1.0V more than 5 times during 10 seconds at 2,000
rpm.
1 time: 0 - 0.3V®0.6 - 1.0V®0 - 0.3V
2 times: 0 - 0.3V®0.6 - 1.0V®0 - 0.3V®0.6 - 1.0V®0 - 0.3V
OK or NG
OK©GO TO 23.
NG (Voltage does not
fluctuate.)©GO TO 28.
NG (Voltage fluctuates
less than 5 times.)©GO TO 21.
BASIC SERVICE PROCEDURE
Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (Cont'd)
EC-50

SEF452Y
Idle Air Volume LearningNBEC0642
SEF454Y
SEF455Y
DESCRIPTIONNBEC0642S01ªIdle Air Volume Learningº is an operation to learn the idle air vol-
ume that keeps each engine within the specific range. It must be
performed under any of the following conditions:
IEach time IACV-AAC valve, throttle body or ECM is replaced.
IIdle speed or ignition timing is out of specification.
PRE-CONDITIONINGNBEC0642S02Before performing ªIdle Air Volume Learningº, make sure that all of
the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are
missed for even a moment.
IBattery voltage: More than 12.9V (At idle)
IEngine coolant temperature: 70 - 99ÉC (158 - 210ÉF)
IPNP switch: ON
IElectric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime running light systems, if
the parking brake is applied before the engine is started the
headlamp will not illuminate.
ICooling fan motor: Not operating
ISteering wheel: Neutral (Straight-ahead position)
IVehicle speed: Stopped
ITransmission: Warmed-up
For A/T models with CONSULT-II, drive vehicle until ªFLUID
TEMP SEº in ªDATA MONITORº mode of ªA/Tº system indi-
cates less than 0.9V.
For A/T models without CONSULT-II, drive vehicle for 10 min-
utes.
OPERATION PROCEDURENBEC0642S03With CONSULT-IINBEC0642S03011. Turn ignition switch ªONº and wait at least 1 second.
2. Turn ignition switch ªOFFº and wait at least 10 seconds.
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic ªPRE-CONDITION-
INGº (previously mentioned) are in good order.
5. Turn ignition switch ªOFFº and wait at least 10 seconds.
6. Start the engine and let it idle for at least 30 seconds.
7. Select ªIDLE AIR VOL LEARNº in ªWORK SUPPORTº mode.
8. Touch ªSTARTº and wait 20 seconds.
9. Make sure that ªCMPLTº is displayed on CONSULT-II screen.
If ªINCMPº is displayed, ªIdle Air Volume Learningº will not be
carried out successfully. In this case, find the cause of the
problem by referring to the NOTE below.
10. Rev up the engine two or three times. Make sure that idle
speed and ignition timing are within specifications.
ITEM SPECIFICATION
Idle speed 750±50 rpm (in ªPº or ªNº position)
Ignition timing 15ɱ5É BTDC (in ªPº or ªNº position)
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BASIC SERVICE PROCEDURE
Idle Air Volume Learning
EC-57

IThe time required for each diagnosis varies with road surface conditions, weather, altitude, individual driv-
ing habits, etc.
Zone A refers to the range where the time required, for the diagnosis under normal conditions*, is the
shortest.
Zone B refers to the range where the diagnosis can still be performed if the diagnosis is not completed
within zone A.
*: Normal conditions refer to the following:
þ Sea level
þ Flat road
þ Ambient air temperature: 20 - 30ÉC (68 - 86ÉF)
þ Diagnosis is performed as quickly as possible under normal conditions.
Under different conditions [For example: ambient air temperature other than 20 - 30ÉC (68 - 86ÉF)], diag-
nosis may also be performed.
Pattern 1:
IThe engine is started at the engine coolant temperature of þ10 to 35ÉC (14 to 95ÉF)
(where the voltage between the ECM terminal 70 and ground is 3.0 - 4.3V).
IThe engine must be operated at idle speed until the engine coolant temperature is greater than 70ÉC
(158ÉF) (where the voltage between the ECM terminal 70 and ground is lower than 1.4V).
IThe engine is started at the fuel tank temperature of warmer than 0ÉC (32ÉF) (where the voltage
between the ECM terminal 92 and ground is less than 4.1V).
Pattern 2:
IWhen steady-state driving is performed again even after it is interrupted, each diagnosis can be conducted.
In this case, the time required for diagnosis may be extended.
Pattern 3:
IThe driving pattern outlined in *2 must be repeated at least 3 times.
Pattern 4:
ITests are performed after the engine has been operated for at least 17 minutes.
IThe accelerator pedal must be held very steady during steady-state driving.
IIf the accelerator pedal is moved, the test must be conducted all over again.
*1: Depress the accelerator pedal until vehicle speed is 90 km/h (56 MPH), then release the accelerator pedal
and keep it released for more than 10 seconds. Depress the accelerator pedal until vehicle speed is 90 km/h
(56 MPH) again.
*2: Operate the vehicle in the following driving pattern.
1) Decelerate vehicle to 0 km/h (0 MPH) and let engine idle.
2) Repeat driving pattern shown below at least 10 times.
IDuring acceleration, hold the accelerator pedal as steady as possible.
SEF414S
*3: Checking the vehicle speed with GST is advised.
Suggested Transmission Gear Position for A/T Models
Set the selector lever in the ªDº position with the overdrive switch turned ON.
Suggested upshift speeds for M/T models
Shown below are suggested vehicle speeds for shifting into a higher gear. These suggestions relate to fuel
economy and vehicle performance. Actual upshift speeds will vary according to road conditions, the weather
and individual driving habits.
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Emission-related Diagnostic Information (Cont'd)
EC-67

Items
(CONSULT-II screen terms)DTC*1 SRT codeTest value/ Test
limit
(GST only)1st trip DTC*1 Reference page
INTK TIM S/CIRC-B2 P1145 Ð Ð X EC-482
CLOSED LOOP-B1 P1148 Ð Ð X EC-491
SWL CON VC SW/CIRC P1165 Ð Ð X EC-493
CLOSED LOOP-B2 P1168 Ð Ð X EC-491
ENG OVER TEMP P1217 Ð Ð X LC-24
IGN SIGNAL-PRIMARY P1320 Ð Ð X EC-499
CPS/CIRCUIT (REF) P1335 Ð Ð X EC-510
CPS/CIRC (POS) COG P1336 Ð Ð X EC-517
EVAP VERY SMALL LEAK P1441 X X X*2 EC-526
PURG VOLUME CONT/V P1444 Ð Ð X EC-541
VENT CONTROL VALVE P1446 Ð Ð X EC-553
EVAP PURG FLOW/MON P1447 X X X*2 EC-561
VENT CONTROL VALVE P1448 Ð Ð X EC-573
FUEL LEVEL SEN/CIRC P1464 Ð Ð X EC-582
VC/V BYPASS/V P1490 Ð Ð X EC-585
VC CUT/V BYPASS/V P1491 Ð Ð X EC-591
A/T DIAG COMM LINE P1605 Ð Ð X EC-603
TP SEN/CIRC A/T P1705 Ð Ð X AT-218
P-N POS SW/CIRCUIT P1706 Ð Ð X EC-604
O/R CLTCH SOL/CIRC P1760 Ð Ð X AT-223
*1: 1st trip DTC No. is the same as DTC No.
*2: These are not displayed with GST.
NOTE:
Regarding R50 models, ª-B1º and ªBK1º indicate right bank and ª-B2º and ªBK2º indicate left bank.
HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATIONNBEC0031S06How to Erase DTC (With CONSULT-II)NBEC0031S0601NOTE:
If the DTC is not for A/T related items (see EC-8), skip steps 2 through 4.
1. If the ignition switch stays ªONº after repair work, be sure to turn ignition switch ªOFFº once. Wait at least
10 seconds and then turn it ªONº (engine stopped) again.
2. Turn CONSULT-II ªONº and touch ªA/Tº.
3. Touch ªSELF-DIAG RESULTSº.
4. Touch ªERASEº. [The DTC in the TCM (Transmission control module) will be erased.] Then touch ªBACKº
twice.
5. Touch ªENGINEº.
6. Touch ªSELF-DIAG RESULTSº.
7. Touch ªERASEº. (The DTC in the ECM will be erased.)
IIf DTCs are displayed for both ECM and TCM (Transmission control module), they need to be erased
individually from the ECM and TCM (Transmission control module).
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Emission-related Diagnostic Information (Cont'd)
EC-72

DESCRIPTION FOR WORK FLOWNBEC0037S01
STEP DESCRIPTION
STEP IGet detailed information about the conditions and the environment when the incident/symptom occurred using
the ªDIAGNOSTIC WORK SHEETº, EC-98.
STEP IIBefore confirming the concern, check and write down (print out using CONSULT-II or GST) the (1st trip) DTC
and the (1st trip) freeze frame data, then erase the DTC and the data. (Refer to EC-72.) The (1st trip) DTC and
the (1st trip) freeze frame data can be used when duplicating the incident at STEP III & IV.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-140.
Study the relationship between the cause, specified by (1st trip) DTC, and the symptom described by the cus-
tomer. (The ªSymptom Matrix Chartº will be useful. See EC-118.)
Also check related service bulletins for information.
STEP IIITry to confirm the symptom and under what conditions the incident occurs.
The ªDIAGNOSTIC WORK SHEETº and the freeze frame data are useful to verify the incident. Connect CON-
SULT-II to the vehicle in DATA MONITOR (AUTO TRIG) mode and check real time diagnosis results.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-140.
If the malfunction code is detected, skip STEP IV and perform STEP V.
STEP IVTry to detect the (1st trip) DTC by driving in (or performing) the ªDTC Confirmation Procedureº. Check and read
the (1st trip) DTC and (1st trip) freeze frame data by using CONSULT-II or GST.
During the (1st trip) DTC verification, be sure to connect CONSULT-II to the vehicle in DATA MONITOR (AUTO
TRIG) mode and check real time diagnosis results.
If the incident cannot be verified, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-140.
In case the ªDTC Confirmation Procedureº is not available, perform the ªOverall Function Checkº instead. The
(1st trip) DTC cannot be displayed by this check, however, this simplified ªcheckº is an effective alternative.
The ªNGº result of the ªOverall Function Checkº is the same as the (1st trip) DTC detection.
STEP VTake the appropriate action based on the results of STEP I through IV.
If the malfunction code is indicated, proceed to TROUBLE DIAGNOSIS FOR DTC PXXXX.
If the normal code is indicated, proceed to the BASIC INSPECTION. (Refer to EC-101.) If CONSULT-II is
available, perform ªDATA MONITOR (SPEC)º mode with CONSULT-II and proceed to the ªTROUBLE DIAGNO-
SIS Ð SPECIFICATION VALUEº, EC-136. (If malfunction is detected, proceed to ªREPAIR REPLACEº.) Then
perform inspections according to the Symptom Matrix Chart. (Refer to EC-118.)
STEP VIIdentify where to begin diagnosis based on the relationship study between symptom and possible causes.
Inspect the system for mechanical binding, loose connectors or wiring damage using (tracing) ªHarness Layoutsº.
Gently shake the related connectors, components or wiring harness with CONSULT-II set in ªDATA MONITOR
(AUTO TRIG)º mode.
Check the voltage of the related ECM terminals or monitor the output data from the related sensors with CON-
SULT-II. Refer to EC-122, 127.
The ªDiagnostic Procedureº in EC section contains a description based on open circuit inspection. A short circuit
inspection is also required for the circuit check in the Diagnostic Procedure. For details, refer to GI-27, ªCircuit
Inspectionº.
Repair or replace the malfunction parts.
If malfunctioning part cannot be detected, perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº,
EC-140.
STEP VIIOnce you have repaired the circuit or replaced a component, you need to run the engine in the same conditions
and circumstances which resulted in the customer's initial complaint.
Perform the ªDTC Confirmation Procedureº and confirm the normal code [DTC No. P0000] is detected. If the
incident is still detected in the final check, perform STEP VI by using a different method from the previous one.
Before returning the vehicle to the customer, be sure to erase the unnecessary (already fixed) (1st trip) DTC in
ECM and TCM (Transmission control module). (Refer to EC-72.)
TROUBLE DIAGNOSIS Ð INTRODUCTION
Work Flow (Cont'd)
EC-100

31 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-57.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 32.
INCMP©1. Follow the construction of ªIdle Air volume Learningº.
2. GO TO 31.
32 CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode with CONSULT-II.
3. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 34.
NG©GO TO 33.
33 CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function.
(ECM may be the cause of a problem, but this is rarely the case.)
2. Perform initialization of NVIS (NATS) system and registration of NVIS (NATS) ignition key IDs. Refer to ªNVIS (NISSAN
VEHICLE IMMOBILIZER SYSTEM Ð NATS)º, EC-74.
©GO TO 31.
34 CHECK IGNITION TIMING AGAIN
Check ignition timing again. Refer to Test No. 30.
OK or NG
OK©GO TO 36.
NG©GO TO 35.
35 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-29, ªInstallationº.
OK or NG
OK©GO TO 33.
NG©1. Repair the timing chain installation.
2. GO TO 31.
36 ERASE UNNECESSARY DTC
After this inspection, unnecessary DTC No. might be displayed.
Erase the stored memory in ECM and TCM (Transmission control module).
Refer to ªHow to Erase Emission-Related Diagnostic Informationº, EC-72 and AT-35, ªHOW TO ERASE DTCº.
©INSPECTION END
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-115

DescriptionNBEC0717The specification (SP) value indicates the tolerance of the value that is displayed in ªDATA MONITOR (SPEC)º
mode of CONSULT-II during normal operation of the Engine Control System. When the value in ªDATA MONI-
TOR (SPEC)º mode is within the SP value, the Engine Control System is confirmed OK. When the value in
ªDATA MONITOR (SPEC)º mode is NOT within the SP value, the Engine Control System may have one or
more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the
MIL.
The SP value will be displayed for the following three items:
IB/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board cor-
rection)
IA/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)
IMAS A/F SE-B1 (The signal voltage of the mass air flow sensor)
Testing ConditionNBEC0718IVehicle driven distance: More than 5,000 km (3,100 miles)
IBarometric pressure: 101.3 kPa (760.0 mmHg, 29.92 inHg)±3 kPa (22.5 mmHg, 0.89 inHg)
IAtmospheric temperature: 20 - 30ÉC (68 - 86ÉF)
IEngine coolant temperature: 75 - 95ÉC (167 - 203ÉF)
ITransmission: Warmed-up*1
IElectrical load: Not applied*2
IEngine speed: Idle
*1: For A/T models, after the engine is warmed up to normal operating temperature, drive vehicle until ªFLUID
TEMP SEº (A/T fluid temperature sensor signal) indicates less than 0.9V.
*2: Rear window defogger switch, air conditioner switch, lighting switch are ªOFFº. Cooling fans are not oper-
ating. Steering wheel is straight ahead.
SEF601Z
Inspection ProcedureNBEC0719NOTE:
Perform ªDATA MONITOR (SPEC)º mode in maximum scale dis-
play.
1. Perform ªBasic Inspectionº, EC-101.
2. Confirm that the testing conditions indicated above are met.
3. Select ªB/FUEL SCHDLº, ªA/F ALPHA-B1º, ªA/F ALPHA-B2º
and ªMAS A/F SE-B1º in ªDATA MONITOR (SPEC)º mode with
CONSULT-II.
4. Make sure that monitor items are within the SP value.
5. If NG, go to ªDiagnostic Procedureº, EC-137.
TROUBLE DIAGNOSIS Ð SPECIFICATION VALUE
Description
EC-136

3 CHECK ABSOLUTE PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch ªONº.
2. Check voltage between absolute pressure sensor terminal 1 and ground with CONSULT-II or tester.
SEF299X
OK or NG
OK©GO TO 4.
NG©Repair harness or connectors.
4 CHECK ABSOLUTE PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between absolute pressure sensor terminal 3 and engine ground.
Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
IHarness for open or short between ECM and absolute pressure sensor
IHarness for open or short between TCM (Transmission Control Module) and absolute pressure sensor
©Repair open circuit or short to ground or short to power in harness or connectors.
6 CHECK ABSOLUTE PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 80 and absolute pressure sensor terminal 2.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 7.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0105 ABSOLUTE PRESSURE SENSOR
Diagnostic Procedure (Cont'd)
EC-162