2003 NISSAN TEANA engine coolant

EC-362
[VQ]
AIR CONDITIONING CUT CONTROL

AIR CONDITIONING CUT CONTROLPFP:23710
Input/Output Signal ChartBBS004XM
*1: This signal is sent to the ECM through CAN communication line.
*2: This signal is sent from the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
System DescriptionBBS004XN
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned OFF.

When the accelerator pedal is fully depressed.

When cranking the engine.

At high engine speeds.

When the engine coolant temperature becomes excessively high.

When operating power steering during low engine speed or low vehicle speed.

When engine speed is excessively low.

When refrigerant pressure is excessively low or high.
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch
Air conditioner ON signal*
1
Air conditioning
cut controlAir conditioner relay*2
Accelerator pedal position sensor Accelerator pedal position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
3
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
3
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensor
Vehicle speed*
1

AUTOMATIC SPEED CONTROL DEVICE (ASCD)
EC-363
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AUTOMATIC SPEED CONTROL DEVICE (ASCD)PFP:18930
System DescriptionBBS004XO
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
BASIC ASCD SYSTEM
Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric throttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE indicator and SET indicator in combination meter. If any
malfunction occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION
Press MAIN switch. (The CRUISE indicator in combination meter illuminates.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET indicator in combination meter illuminates.)
ACCELERATOR OPERATION
If the RESUME/ACCELERATE switch is pressed during cruise control driving, increase the vehicle speed until
the switch is released or vehicle speed reaches maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION
When any of following conditions exist, cruise operation will be canceled.

CANCEL switch is pressed

More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)

Brake pedal is depressed

Selector lever is changed to N, P, R position

Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed

VDC/TCS system is operated
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform
the driver by blinking indicator lamp.

Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may
blink slowly.
When the engine coolant temperature decreases to the normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/
ACCELERATE switch.

Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
Sensor Input signal to ECM ECM function Actuator
ASCD brake switch Brake pedal operation
ASCD vehicle speed controlElectric throttle control
actuator Stop lamp switch Brake pedal operation
ASCD steering switch ASCD steering switch operation
Park/Neutral position (PNP)
switchGear position
Wheel sensor Vehicle speed*
TCM Powertrain revolution*

EC-376
[VQ]
ON BOARD DIAGNOSTIC (OBD) SYSTEM

FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, engine coolant temperature, short term
fuel trim, long term fuel trim, engine speed, vehicle speed, base fuel schedule and intake air temperature at
the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II. For
details, see EC-427, "
Freeze Frame Data and 1st Trip Freeze Frame Data" .
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/MI 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.
Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM mem-
ory is erased. Procedures for clearing the ECM memory are described in EC-376, "
HOW TO ERASE EMIS-
SION-RELATED DIAGNOSTIC INFORMATION" .
HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION
How to Erase DTC
WITH CONSULT-II
The emission related diagnostic information in the ECM can be erased by selecting “ERASE” in the “SELF-
DIAG RESULTS” mode with CONSULT-II.
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-II ON and touch “ENGINE”.
3. Touch “SELF-DIAG RESULTS”.
4. Touch “ERASE”. (The DTC in the ECM will be erased.)
WITHOUT CONSULT-II
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once.
2. Wait at least 10 seconds and then turn it ON (engine stopped) again.
3. Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal. Refer to
EC-378, "
HOW TO SWITCH DIAGNOSTIC TEST MODE" .

If the battery is disconnected, the emission-related diagnostic information will be lost within 24
hours.

The following data are cleared when the ECM memory is erased.
–Diagnostic trouble codes
–1st trip diagnostic trouble codes
–Freeze frame data
PBIB2392E

EC-380
[VQ]
ON BOARD DIAGNOSTIC (OBD) SYSTEM

A particular trouble code can be identified by the number of four-digit numeral flashes. The “zero” is indicated
by the number of ten flashes. The length of time the 1,000th-digit numeral flashes on and off is 1.2 seconds
consisting of an ON (0.6-second) - OFF (0.6-second) cycle.
The 100th-digit numeral and lower digit numerals consist of a 0.3-second ON and 0.3-second OFF cycle.
A change from one digit numeral to another occurs at an interval of 1.0-second OFF. In other words, the later
numeral appears on the display 1.3 seconds after the former numeral has disappeared.
A change from one trouble code to another occurs at an interval of 1.8-second OFF.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC 0000 refers to no mal-
function. (See EC-347, "
INDEX FOR DTC" )
How to Erase Diagnostic Test Mode II (Self-diagnostic Results)
The DTC can be erased from the back up memory in the ECM by depressing accelerator pedal. Refer to EC-
378, "HOW TO SWITCH DIAGNOSTIC TEST MODE" .

If the battery is disconnected, the DTC will be lost from the backup memory within 24 hours.

Be careful not to erase the stored memory before starting trouble diagnoses.
DIAGNOSTIC TEST MODE II — HEATED OXYGEN SENSOR 1 MONITOR
In this mode, the MI displays the condition of the fuel mixture (lean or rich) which is monitored by the heated
oxygen sensor 1.
*: Maintains conditions just before switching to open loop.
To check the heated oxygen sensor 1 function, start engine in the Diagnostic Test Mode II and warm it up until
engine coolant temperature indicator points to the middle of the gauge.
Next run engine at about 2,000 rpm for about 2 minutes under no load conditions. Then make sure that the MI
comes ON more than 5 times within 10 seconds with engine running at 2,000 rpm under no load.
MI Fuel mixture condition in the exhaust gas Air fuel ratio feedback control condition
ON Lean
Closed loop system
OFF Rich
*Remains ON or OFF Any condition Open loop system

BASIC SERVICE PROCEDURE
EC-381
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BASIC SERVICE PROCEDUREPFP:00018
Basic InspectionBBS004Y0
1. INSPECTION START
1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
–Harness connectors for improper connections
–Wiring harness for improper connections, pinches and cut
–Vacuum hoses for splits, kinks and improper connections
–Hoses and ducts for leaks
–Air cleaner clogging
–Gasket
3. Confirm that electrical or mechanical loads are not applied.
–Headlamp switch is OFF.
–Air conditioner switch is OFF.
–Rear window defogger switch is OFF.
–Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature
indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no
load.
6. Make sure that no DTC is displayed with CONSULT-II or ECM
[Diagnostic Test Mode II (Self-diagnostic results)]
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2. REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnostic Procedure.
>> GO TO 3.
SEF983U
SEF976U
SEF977U

BASIC SERVICE PROCEDURE
EC-389
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Procedure After Replacing ECMBBS005KQ
When replacing ECM, the following procedure must be performed.
1. Perform initialization of NATS system and registration of all NATS ignition key IDs. Refer to BL-142, "
ECM
Re-Communicating Function" .
2. Perform EC-389, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-389, "
Throttle Valve Closed Position Learning" .
4. Perform EC-389, "
Idle Air Volume Learning" .
Accelerator Pedal Released Position LearningBBS004Y2
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.
Throttle Valve Closed Position LearningBBS004Y3
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to learn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningBBS004Y4
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific
range. It must be performed under any of the following conditions:

Each time electric throttle control actuator or ECM is replaced.

Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, 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.

Battery voltage: More than 12.9V (At idle)

Engine coolant temperature: 70 - 100°C (158 - 212°F)

PNP switch: ON

Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)

Steering wheel: Neutral (Straight-ahead position)

Vehicle speed: Stopped

Transmission: Warmed-up
–A/T models
 With CONSULT-II: Drive vehicle until “FLUID TEMP SE” in “DATA MONITOR” mode of “A/T” system indi-
cates less than 0.9V.
 Without CONSULT-II: Drive vehicle for 10 minutes.

EC-400
[VQ]
TROUBLE DIAGNOSIS

DTC Inspection Priority ChartBBS004Y7
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
If DTC U1000 and/or U1001 is displayed with other DTC, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-458, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .
Priority Detected items (DTC)
1

U1000 U1001 CAN communication line

P0102 P0103 Mass air flow sensor

P0117 P0118 Engine coolant temperature sensor

P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor

P0327 P0328 Knock sensor

P0335 Crankshaft position sensor (POS)

P0340 P0345 Camshaft position sensor (PHASE)

P0605 ECM

P1229 Sensor power supply

P1610 - P1615 NATS

P1700 CVT control system

P1706 Park/Neutral position (PNP) switch

P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
2

P0132 P0134 P0152 P0154 Heated oxygen sensor 1

P0550 Power steering pressure sensor

P1065 ECM power supply

P 1111 P 11 3 6 I n ta k e v a l v e t i m i n g c o n t r o l s o l e n o i d v a l v e

P1122 Electric throttle control function

P1124 P1126 P1128 Electric throttle control actuator

P1217 Engine over temperature (OVERHEAT)

P1720 Vehicle speed sensor

P1805 Brake switch
3

P0011 P0021 Intake valve timing control

P1121 Electric throttle control actuator

P1211 TCS control unit

P1212 TCS communication line

P1564 ASCD steering switch

P1572 ASCD brake switch

P1574 ASCD vehicle speed sensor

P1715 Primary speed sensor

EC-402
[VQ]
TROUBLE DIAGNOSIS

Symptom Matrix ChartBBS004Y9
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit 11232 22 3 2EC-690
Fuel pressure regulator system334444444 4EC-392
Fuel injector circuit 11232 22 2EC-684
Evaporative emission system 334444444 4EC-366
Air Positive crankcase ventilation sys-
tem
334444444 41EC-370
Incorrect idle speed adjustment 1 1 1 1 1EC-381
Electric throttle control actuator 112332222 2 2EC-552,
EC-555
IgnitionIncorrect ignition timing adjustment 33111 11 1EC-381
Ignition circuit 11222 22 2EC-735
Main power supply and ground circuit22333 33 23EC-451
Mass air flow sensor circuit
1
122
222 2EC-466
Engine coolant temperature sensor circuit
333EC-474
Heated oxygen sensor 1 circuitEC-486
,
EC-496
,
EC-696
Throttle position sensor circuit
22EC-479
,
EC-505
,
EC-586
,
EC-588
,
EC-645
Accelerator pedal position sensor circuit 3 2 1EC-590
,
EC-631
,
EC-638
,
EC-652
Knock sensor circuit 2 3EC-512
Crankshaft position sensor (POS) circuit 2 2EC-517
Camshaft position sensor (PHASE) circuit 3 2EC-524
Vehicle speed signal circuit 2 3 3 3EC-762
Power steering pressure sensor circuit 2 3 3EC-533
ECM 22333333333EC-538,
EC-541