NISSAN PRIMERA 1999 Electronic Repair Manual
Page 351 of 2267
TER-
MINAL
NO.WIRE
COLORITEM CONDITIOND ATA
(DC Voltage and
Pulse Signal)
403 GY Air conditioner switchEngine is running.
Both air conditioner switch and blower
switch are ªONº (Compressor operates)Approximately 0V
Engine is running.
Air conditioner switch is ªOFFºBATTERY VOLTAGE
(11 - 14V)
405 R/G Stop lamp switchIgnition switch ªONº
Brake pedal released0V
Ignition switch ªONº
Brake pedal depressedBattery voltage
(11 - 14V)
410 ORImmobilizer communica-
tionIgnition switch ªONº
BATTERY VOLTAGE
(4 - 14V)
416 R/B Brake switch 2Ignition switch ªONº
Brake pedal releasedBattery voltage
(11 -14V)
Ignition switch ªONº
Brake pedal depressed0V
417 OR/WVehicle speed sensor or
ABS actuator and elec-
tric unit (control unit)Engine is running.
Lift up the vehicle.
In 2nd gear position
Vehicle speed is 40 km/h (25 mph)0 - Approximately 4.2V
SEF552S
420 BR/W
Data link connector for
CONSULT-IIEngine is running.
Idle speed (CONSULT-II is connected and
turned on)Approximately4-9V
415 G/RApproximately 0V
425 BRAccelerator position sen-
sor groundEngine is running.
Idle speedApproximately 0V
433 LG/WAccelerator position sen-
sor power supplyIgnition switch ªONº
Approximately 5V
434 W/PUAccelerator position sen-
sorIgnition switch ªONº
Accelerator pedal released0.4 - 0.6V
Ignition switch ªONº
Accelerator pedal fully depressedApproximately 4.0V
TROUBLE DIAGNOSIS Ð General DescriptionCD20T
ECM Terminals and Reference Value (Cont'd)
EC-57
Page 352 of 2267
TER-
MINAL
NO.WIRE
COLORITEM CONDITIOND ATA
(DC Voltage and
Pulse Signal)
435 GY/RAccelerator position
switch (Idle)Ignition switch ªONº
Accelerator pedal releasedApproximately 0V
Ignition switch ªONº
Accelerator pedal depressedApproximately 2.7V
442 B/Y Start signalIgnition switch ªONº
Approximately 0V
Ignition switch ªSTARTº
BATTERY VOLTAGE
(11 - 14V)
439 L/OR TachometerEngine is running.
(Warm-up condition)
Idle speedApproximately 1.1 - 1.5V
SEF550S
Engine is running.
Engine speed is 2,000 rpmApproximately 1.1 - 1.5V
SEF551S
507 BR/Y Ignition switchIgnition switch ªLOCKº
0V
Ignition switch ªONº
BATTERY VOLTAGE
(11 - 14V)
TROUBLE DIAGNOSIS Ð General DescriptionCD20T
ECM Terminals and Reference Value (Cont'd)
EC-58
Page 353 of 2267
Main Power Supply and Ground Circuit
YEC100A
TROUBLE DIAGNOSIS FOR POWER SUPPLYCD20T
EC-59
Page 354 of 2267
INSPECTION START
Start engine.
Is engine running?
Ye s
ENo
CHECK POWER SUPPLY-I.
1. Disconnect ECM harness
connector.
2. Turn ignition switch to
ªONº position.
3. Check voltage between
ECM connector terminal
507and ground
Voltage: Battery voltage
If NG, check the following:
l10A fuselHarness connectorsM52,F103
lHarness for open or
short-circuit between
ECM and ignition switch.
If NG, replace 10A fuse or
repair harness or connec-
tors.
OK 1. Stop engine.
2. Disconnect ECM harness connector.
3. Turn ignition switch to ªONº position.F
CHECK POWER SUPPLY-II.
1. Short between ECM connector terminal
325and engine ground with a jump
wire.
2. Check voltage between ECM terminals
107,108,109and ground.
Voltage: Battery voltage
NG
EOK
Go toªCHECK
GROUND CIRCUITº on
page EC-CD-61.
CHECK HARNESS CONTINUITY
BETWEEN ENGINE CONTROL MODULE
RELAY AND ECM
Check harness continuity between ECM
connector terminals
107,108,109and
ECM relay connector terminal
p5.
Continuity should exist.
If OK, check harness for short.
OK
ENG
Check the following:
lHarness connectorsM89,F96
lHarness for open or
short-circuit between
ECM relay and ECM.
If NG, repair harness or
connectors.
pA
NEF863
YEC327 ECM relay
NEF186A
NEF187A
NEF188A
ECM relay
connector
H
H
H
H
H
TROUBLE DIAGNOSIS FOR POWER SUPPLYCD20T
Main Power Supply and Ground Circuit
(Cont'd)
EC-60
Page 355 of 2267
pA
CHECK VOLTAGE BETWEEN ENGINE
CONTROL MODULE RELAY AND
GROUND.
Check voltage between ECM relay connec-
tor terminals
p2,p3and ground with
CONSULT-II or tester.
Voltage: Battery voltage
OK
ENG
Check the following:
l15A fuselHarness for open or
short-circuit between
ECM relay and battery.
If NG, replace fuse or repair
harness or connectors.
CHECK OUTPUT SIGNAL CIRCUIT.
Check harness continuity between ECM
connector terminal
325and ECM relay
connector terminal
p1.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENGlCheck harness connec-
torsE43,F2
Repair harness or connec-
tors.
CHECK ECM RELAY.
1. Apply 12V direct current between ECM
relay connector terminals
p1andp2.
2. Check continuity between engine control
module relay connector terminals
p3and
p5.
12V (
p1-p2) applied:
Continuity exists.
No voltage applied:
No continuity
OK
ENG
Replace ECM relay.
CHECK GROUND CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Check harness continuity between ECM
connector terminals
104,105,106
and engine ground.
Continuity should exist.
If resistance is too high, loosen, clean and
retighten engine ground.
If OK, check harness for short-circuit.
OK
ENG
Repair harness or connec-
tors.
Check ECM pin terminals for damage and
check the connection of ECM harness con-
nector.
INSPECTION END
YEC352 ECM relay
connector
NEF189A ECM relay
connector
YEC354 ECM relay
connector
NEF190A
NEF399 Engine ground
H
H
H
H
H
H
TROUBLE DIAGNOSIS FOR POWER SUPPLYCD20T
Main Power Supply and Ground Circuit
(Cont'd)
EC-61
Page 356 of 2267
Mass Air Flow Sensor (MAFS)
The mass air flow sensor measures the amount of intake air by
analysing a part of the entire flow. When intake air flows into the
intake manifold, heat is withdrawn from the hot film. By regulat-
ing the electrical current that flows through the hot film, the ECM
maintains the hot film temperature on a constant level. The
amount of electric current that is needed to keep the hot film on
a constant temperature level is proportional to the mass of air
that flows into the engine.
Malfunction is detected when...Check Items
(Possible Cause)
lAn excessively high or low voltage from the sensor is
entered to ECM.lHarness or connectors
(The sensor circuit is open or shorted.)
lMass air flow sensor
DIAGNOSTIC TROUBLE CONFIRMATION
PROCEDURE
1) Turn ignition switch to ªONº position.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and wait for at least 20 seconds.
NEF663
TROUBLE DIAGNOSIS 1CD20T
EC-62
Page 357 of 2267
YEC799
BATTERY
Refer to EL-POWER.: Detectable line for DTC
: Non-detectable line for DTC
ENGINE
CONTROL
MODULE
RELAYMASS AIR
FLOW SEN-
SOR
ECM
TROUBLE DIAGNOSIS 1CD20T
Mass Air Flow Sensor (MAFS) (Cont'd)
EC-63
Page 358 of 2267
DIAGNOSTIC PROCEDURE
INSPECTION START
CHECK POWER SUPPLY.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect mass air flow sensor harness
connector.
3. Turn ignition switch to ªONº position.
4. Check voltage between mass air flow
sensor connector terminal
p2and
ground.
Voltage: Battery positive voltage
OK
ENG
Repair harness or connec-
tors.
CHECK GROUND CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect ECM harness connector.
3. Check harness continuity between mass
air flow sensor connector terminal
p3and ECM connector terminal218.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG
Repair harness or connec-
tors.
CHECK INPUT SIGNAL CIRCUIT.
Check harness continuity between mass air
flow sensor connector terminal
p4and
ECM connector terminal223, mass air
flow sensor connector terminal
p5and
ECM connector terminal224.
Continuity should exist.
If OK, check harness for short.
OK
ENG
Repair harness or connec-
tors.
CHECK COMPONENT
(Mass air flow sensor).
Refer to ªCOMPONENT INSPECTIONº on
next page.
OK
ENG
Replace mass air flow sen-
sor.
Disconnect and reconnect harness connec-
tors in the circuits. Then retest.
Trouble is not fixed.
Check ECM pin terminals for damage or the
connection of ECM harness connector.
INSPECTION END
NEF788 Mass air flow sensor harness connector
NEF789
Mass air flow
sensor connector
NEF191A
Mass air
flow sensor
connector
NEF192A
Mass air flow sensor
connector
H
H
H
H
H
H
H
TROUBLE DIAGNOSIS 1CD20T
Mass Air Flow Sensor (MAFS) (Cont'd)
EC-64
Page 359 of 2267
COMPONENT INSPECTION
Mass air flow sensor
1. Turn ignition switch to ªONº position.
2. Start engine and warm it up sufficiently.
3. Check voltage between mass air flow sensor connector ter-
minal
p5and ground.
Conditions Voltage V
Ignition switch ªONº position (Engine stopped.)Approximately 1.0
Idle (Engine is warmed-up sufficiently.)1.9 - 2.3
4. If NG, remove mass air flow sensor from air duct. Check hot
film for damage or dust.
NEF792 Mass air flow sensor
connector
NEF669
TROUBLE DIAGNOSIS 1CD20T
Mass Air Flow Sensor (MAFS) (Cont'd)
EC-65
Page 360 of 2267
Engine Coolant Temperature (ECT) Sensor
The engine coolant temperature sensor is used to detect the
engine coolant temperature. The sensor modifies a voltage sig-
nal from the ECM. The modified signal returns to the ECM as the
engine coolant temperature input. The sensor uses a thermistor
which is sensitive to the change in temperature. The electrical
resistance of the thermistor decreases as temperature
increases.
<Reference data>
Engine coolant
temperature
ÉC (ÉF)Voltage
(V)Resistance
(kW)
þ10 (14)4.4 7.0 - 11.4
20 (68)3.5 2.1 - 2.9
50 (122)2.3 0.68 - 1.00
90 (194)1.0 0.236 - 0.260
Malfunction is detected when ...Check Items
(Possible Cause)
lAn excessively high or low voltage from the sensor is
entered to ECM.lHarness or connectors
(The sensor circuit is open or shorted.)
lEngine coolant temperature sensor
DIAGNOSTIC TROUBLE CONFIRMATION
PROCEDURE
1) Turn ignition switch to ªONº position.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 5 seconds.
SEF594K
SEF012P
TROUBLE DIAGNOSIS 2CD20T
EC-66