2003 NISSAN TEANA Power

EC-746
[VQ]
IGNITION SIGNAL

Component InspectionBBS00563
IGNITION COIL WITH POWER TRANSISTOR
CAUTION:
Do the following procedure in the place where ventilation is good without the combustible.
1. Turn ignition switch OFF.
2. Disconnect ignition coil harness connector.
3. Check resistance between ignition coil terminals as follows.
4. If NG, Replace ignition coil with power transistor.
If OK, go to next step.
5. Turn ignition switch OFF.
6. Reconnect all harness connectors disconnected.
7. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
Do not use CONSULT-II to release fuel pressure, or fuel pres-
sure applies again during the following procedure.
8. Start engine.
9. After engine stalls, crank it two or three times to release all fuel
pressure.
10. Turn ignition switch OFF.
11. Remove ignition coil harness connectors to avoid the electrical
discharge from the ignition coils.
12. Remove ignition coil and spark plug of the cylinder to be
checked.
13. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
14. Connect spark plug and harness connector to ignition coil.
15. Fix ignition coil using a rope etc. with gap of 13 - 17 mm
between the edge of the spark plug and grounded metal portion
as shown in the figure.
16. Crank engine for about 3 seconds, and check whether spark is
generated between the spark plug and the grounded part.
CAUTION:

Do not approach to the spark plug and the ignition coil
within 50cm. Be careful not to get an electrical shock
while checking, because the electrical discharge voltage
becomes 20kV or more.

It might cause to damage the ignition coil if the gap of more than 17 mm is taken.
NOTE:
When the gap is less than 13 mm, the spark might be generated even if the coil is malfunctioning.
17. If NG, Replace ignition coil with power transistor.
Terminal No. (Polarity) Resistance Ω [at 25°C (77°F)]
1 and 2 Except 0 or ∞
1 and 3
Except 0
2 and 3
Spark should be generated.
PBIB0847E
PBIB2110E
PBIB2325E

IGNITION SIGNAL
EC-747
[VQ]
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EC

CONDENSER
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Check resistance between condenser terminals 1 and 2.
Removal and InstallationBBS00564
IGNITION COIL WITH POWER TRANSISTOR
Refer to EM-152, "IGNITION COIL" . Resistance: Above 1 MΩ [at 25°C (77°F)]
PBIB0794E

EC-750
[VQ]
REFRIGERANT PRESSURE SENSOR

Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureBBS00571
1. CHECK REFRIGERANT PRESSURE SENSOR OVERALL FUNCTION
1. Start engine and warm it up to normal operating temperature.
2. Turn A/C switch and blower fan switch ON.
3. Check voltage between ECM terminal 70 and ground with CON-
SULT-II or tester.
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
2. CHECK GROUND CONNECTIONS
1. Turn A/C switch and blower fan switch OFF.
2. Turn ignition switch OFF.
3. Loosen and retighten two ground screws on the body.
Refer to EC-457, "
Ground Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
49 BR/WSensor power supply
(Refrigerant pressure sen-
sor)[Ignition switch: ON]Approximately 5V
67 B Sensor ground[Engine is running]

Warm-up condition

Idle speedApproximately 0V
70 W Refrigerant pressure sensor[Engine is running]

Warm-up condition

Both A/C switch and blower fan switch: ON
(Compressor operates.)1.0 - 4.0V
Voltage: 1.0 - 4.0V
PBIB1188E
PBIB2160E

REFRIGERANT PRESSURE SENSOR
EC-751
[VQ]
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EC

3. CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect refrigerant pressure sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between refrigerant pressure sensor terminal 1
and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E39, F41

Harness for open or short between ECM and refrigerant pressure sensor
>> Repair harness or connectors.
5. CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between refrigerant pressure sensor terminal 3 and ECM terminal 67.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E39, F41

Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB2112E
Voltage: Approximately 5V
PBIB0188E
Continuity should exist.

EC-752
[VQ]
REFRIGERANT PRESSURE SENSOR

7. CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 70 and refrigerant pressure sensor terminal 2.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> GO TO 8.
8. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E39, F41

Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
9. CHECK INTERMITTENT INCIDENT
Refer to EC-450, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace refrigerant pressure sensor.
NG >> Repair or replace.
Removal and InstallationBBS00572
REFRIGERANT PRESSURE SENSOR
Refer to ATC-144, "Removal and Installation of Refrigerant Pressure Sensor" . Continuity should exist.

VIAS
EC-753
[VQ]
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VIASPFP:14956
DescriptionBBS00565
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
When the engine is running at medium speed, the ECM sends the ON signal to the VIAS control solenoid
valve. This signal introduces the intake manifold vacuum into the power valve actuator and therefore closes
the power valve.
Under this condition, the effective intake manifold length is equivalent to the total length of passage A and pas-
sage B. This long intake manifold provides increased amount of intake air, which results in improved suction
efficiency and higher torque.
When engine is running at low or high speed, the ECM sends the OFF signal to the VIAS control solenoid
valve and the power valve is opened.
Under this condition, the effective intake manifold length is equivalent to the length of passage B. This short-
ened intake manifold length results in enhanced engine output due to reduced suction resistance under high
speeds.
COMPONENT DESCRIPTION
Power Valve
The power valve is installed in intake manifold collector and used to
control the suction passage of the variable induction air control sys-
tem. It is set in the fully closed or fully opened position by the power
valve actuator operated by the vacuum stored in the surge tank. The
vacuum in the surge tank is controlled by the VIAS control solenoid
valve.
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
VIAS control VIAS control solenoid valve Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Battery Battery voltage*
PBIB1822E
PBIB2108E

EC-754
[VQ]
VIAS

VIAS Control Solenoid Valve
The VIAS control solenoid valve cuts the intake manifold vacuum
signal for power valve control. It responds to ON/OFF signals from
the ECM. When the solenoid is OFF, the vacuum signal from the
intake manifold is cut. When the ECM sends an ON signal the coil
pulls the plunger downward and feeds the vacuum signal to the
power valve actuator.
CONSULT-II Reference Value in Data Monitor ModeBBS00566
Specification data are reference values.
PBIB2108E
MONITOR ITEM CONDITION SPECIFICATION
VIAS S/V

Engine: After warming up1,800 - 3,600 rpm (VQ35DE engine)
1,800 - 3,750 rpm (VQ23DE engine)ON
Except above conditions OFF

EC-756
[VQ]
VIAS

Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
29 Y/G VIAS control solenoid valve[Engine is running]

Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]

Engine speed:
Between 1,800 and 3,600 rpm
(VQ35DE engine)
Between 1,800 and 3,750 rpm
(VQ23DE engine)0 - 1.0V
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120R/G
R/GPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)