NISSAN ALMERA 2001 Service Manual

Wiring DiagramNJEC0194SEDAN MODELS AND HATCHBACK MODELS WITH
ECM IN ENGINE COMPARTMENT
NJEC0194S03
HEC789
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Wiring Diagram
EC-307

HATCHBACK MODELS WITH ECM IN CABINNJEC0194S04
HEC944
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Wiring Diagram (Cont'd)
EC-308

Diagnostic ProcedureNJEC0195
1 CHECK FOR EXHAUST AIR LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust air leak before the three way catalyst.
SEF099P
OK or NG
OK©GO TO 2.
NG©Repair or replace.
2 CHECK HEATED OXYGEN SENSOR 1 (FRONT) CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect heated oxygen sensor 1 (front) harness connector and ECM harness connector.
SEF012XA
3. Check harness continuity between ECM terminal 62 and heated oxygen sensor 1 (front) harness connector terminal 2.
Refer to wiring diagram.
Continuity should exist.
4. Check harness continuity between ECM terminal 62 [or heated oxygen sensor 1 (front) harness connector terminal 2]
and ground.
Continuity should not exist.
5. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 3.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Diagnostic Procedure
EC-309

3 CHECK FUEL PRESSURE
1. Release fuel pressure to zero.
Refer to EC-40.
2. Install fuel pressure gauge and check fuel pressure.
At idling:
When fuel pressure regulator valve vacuum hose is connected.
Approximately 235 kPa (2.35 bar, 2.4 kg/cm
2, 34 psi)
When fuel pressure regulator valve vacuum hose is disconnected.
Approximately 294 kPa (2.94 bar, 3.0 kg/cm
2, 43 psi)
OK or NG
OK©GO TO 5.
NG©GO TO 4.
4 DETECT MALFUNCTIONING PART
Check the following.
+Fuel pump and circuit (Refer to EC-561.)
+Fuel pressure regulator (Refer to EC-41.)
©Repair or replace.
5 CHECK MASS AIR FLOW SENSOR
With CONSULT-II
Check ªMASS AIR FLOWº in ªDATA MONITORº mode with CONSULT-II.
at idling: 1.0 - 4.0 g´m/sec
at 2,500 rpm: 5.0 - 10.0 g´m/sec
With GST
Check mass air flow sensor signal in MODE 1 with GST.
at idling: 1.0 - 4.0 g´m/sec
at 2,500 rpm: 5.0 - 10.0 g´m/sec
OK or NG
OK©GO TO 6.
NG©Check connectors for rusted terminals or loose connections in the mass air flow sensor
circuit or engine grounds. Refer to EC-191.
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Diagnostic Procedure (Cont'd)
EC-310

6 CHECK FUNCTION OF INJECTORS
With CONSULT-II
1. Install all parts removed.
2. Start engine.
3. Perform ªPOWER BALANCEº in ªACTIVE TESTº mode with CONSULT-II.
SEF190Y
4. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-II
1. Install all parts removed.
2. Start engine.
3. Listen to each injector operating sound.
MEC703B
Clicking noise should be heard.
OK or NG
OK©GO TO 7.
NG©Perform trouble diagnosis for ªINJECTORSº, EC-542.
7 REMOVE INJECTOR
1. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
2. Turn ignition switch ªOFFº.
3. Remove injector assembly. Refer to EC-41.
Keep fuel hose and all injectors connected to injector gallery.
©GO TO 8.
8 CHECK INJECTOR
1. Disconnect all injector harness connectors.
2. Disconnect all ignition coil harness connectors.
3. Prepare pans or saucers under each injectors.
4. Crank engine for about 3 seconds.
Make sure fuel does not drip from injector.
OK or NG
OK (Does not drip)©GO TO 9.
NG (Drips)©Replace the injectors from which fuel is dripping. Always replace O-ring with new one.
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Diagnostic Procedure (Cont'd)
EC-311

9 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
©INSPECTION END
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Diagnostic Procedure (Cont'd)
EC-312

SEF463TA
Component DescriptionNJEC0196The fuel tank temperature sensor is used to detect the fuel tem-
perature inside the fuel tank. The sensor modifies a voltage signal
from the ECM. The modified signal returns to the ECM as the fuel
temperature input. The sensor uses a thermistor which is sensitive
to the change in temperature. The electrical resistance of the ther-
mistor decreases as temperature increases.
SEF012P

Fluid temperature
ÉC (ÉF)Voltage*
VResistance
kW
20 (68) 3.5 2.3 - 2.7
50 (122) 2.2 0.79 - 0.90
*: These data are reference values and are measured between ECM terminal 82
(Fuel tank temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.
On Board Diagnosis LogicNJEC0197
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0180
0180+An excessively high or low voltage is sent to ECM.+Harness or connectors
(The sensor circuit is open or shorted.)
+Fuel tank temperature sensor
SEF194Y
DTC Confirmation ProcedureNJEC0198NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
With CONSULT-II
1) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 5 seconds.
If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-316.
DTC P0180 FUEL TANK TEMPERATURE SENSOR (WHERE FITTED)QG
Component Description
EC-313

With GST
Follow the procedure ªWith CONSULT-IIº above.
DTC P0180 FUEL TANK TEMPERATURE SENSOR (WHERE FITTED)QG
DTC Confirmation Procedure (Cont'd)
EC-314

Wiring DiagramNJEC0199
HEC897
DTC P0180 FUEL TANK TEMPERATURE SENSOR (WHERE FITTED)QG
Wiring Diagram
EC-315

Diagnostic ProcedureNJEC0200
1 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect fuel level sensor unit harness connector.
JEF135Y
3. Turn ignition switch ªONº.
4. Check voltage between terminal 2 and ground with CONSULT-II or tester.
SEF603Y
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors F111, M73
+Harness connectors M81, B38
+Harness for open or short between ECM and fuel level sensor unit
©Repair harness or connector.
3 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between fuel level sensor unit harness connector terminal 1 and body 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 5.
NG (Sedan)©Repair open circuit or short to ground or short to power in harness or connectors.
NG (Hatchback)©GO TO 4.
DTC P0180 FUEL TANK TEMPERATURE SENSOR (WHERE FITTED)QG
Diagnostic Procedure
EC-316