air condition NISSAN PICK-UP 1998 Owner's Guide

TERMINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC voltage)
4 L/RECCS relay (Self-
shutoff)Engine is running.
Ignition switch ``OFF''
For a few seconds after turning ignition
switch ``OFF''0-1V
Ignition switch ``OFF''
A few seconds passed after turning ignition
switch ``OFF''BATTERY VOLTAGE
(11 - 14V)
6 B/P ECCS groundEngine is running.
Idle speedEngine ground
7W
Data link connec-
tor for CONSULTEngine is running.
Idle speedConnect CONSULT and select DATA
MONITOR mode.Approximately 0.1V
14 Y/RApproximately 3.5V
15 LApproximately4-6V
23 LApproximately 0V
11 G/RAir conditioner
relayEngine is running.
Both air conditioner switch and blower fan
switch are ``ON''. (Compressor operates.)Approximately 1V
Engine is running.
Air conditioner switch is ``OFF''.BATTERY VOLTAGE
(11 - 14V)
12 G/YSwirl control valve
control solenoid
valveEngine is running.
Idle speed0-1V
Engine is running.
Engine speed is above 3,600 rpm.BATTERY VOLTAGE
(11 - 14V)
13 B/P ECCS groundEngine is running.
Idle speedEngine ground
16 BMass air flow
sensorEngine is running.
(Warm-up condition)
Idle speed1.3 - 1.7V
Engine is running.
(Warm-up condition)
Engine speed is 2,500 rpm.1.7 - 2.1V
17 WMass air flow
sensor groundEngine is running.
(Warm-up condition)
Idle speed0.005 - 0.02V
18 LG/REngine coolant
temperature sen-
sorEngine is running.
Approximately 0 - 4.8V
Output voltage varies with
engine coolant temperature.
19 WHeated oxygen
sensorEngine is running.
After warming up sufficiently and engine
speed is 2,000 rpm0 - Approximately 1.0V
(periodically change)
20 LGThrottle position
sensorIgnition switch ``ON''
(Warm-up condition)
Accelerator pedal released0.35 - 0.65V
Ignition switch ``ON''
Accelerator pedal fully depressedApproximately 4V
21
29B/G
B/GSensors' groundEngine is running.
(Warm-up condition)
Idle speed0.001 - 0.02V
TROUBLE DIAGNOSIS Ð General DescriptionKA
ECM Terminals and Reference Value
(Cont'd)
EC-70

TERMINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC voltage)
22
30WCamshaft position
sensor (REF)
(180É signal)Engine is running.
(Warm-up condition)
Idle speedApproximately 0.4V
SEF064U
Engine is running.(Warm-up condition)
Engine speed is 2,000 rpm.Approximately 0.4V
SEF065U
24 R/WMalfunction indi-
cator lampIgnition switch ``ON''
Approximately 1.5V
Engine is running.
Idle speedBATTERY VOLTAGE
(11 - 14V)
26 Y/LIntake air tem-
perature sensorEngine is running.
Approximately 0 - 4.8V
Output voltage varies with
intake air temperature.
31
40BCamshaft position
sensor (POS)
(1É signal)Engine is running.
(Warm-up condition)
Idle speedApproximately 2.5V
SEF066U
Engine is running.(Warm-up condition)
Engine speed is 2,000 rpm.Approximately 2.5V
SEF067U
TROUBLE DIAGNOSIS Ð General DescriptionKA
ECM Terminals and Reference Value
(Cont'd)
EC-71

TERMINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC voltage)
32 W/LVehicle speed
sensorIgnition switch ``ON''
Jack up all wheels and run engine at idle in
1st position.Varies from 0 to 5V
SEF068U
34 B/Y Start signalIgnition switch ``ON''
Approximately 0V
Ignition switch ``START''
BATTERY VOLTAGE
(11 - 14V)
35 L/BNeutral position
switchIgnition switch ``ON''
Neutral position0V
Ignition switch ``ON''
Except the above gear positionApproximately 5V
36 B/L Ignition switchIgnition switch ``OFF''
0V
Ignition switch ``ON''
BATTERY VOLTAGE
(11 - 14V)
37 PUThrottle position
sensor power sup-
plyIgnition switch ``ON''
Approximately 5V
38
47B/WPower supply for
ECMIgnition switch ``ON''
BATTERY VOLTAGE
(11 - 14V)
39 B ECCS groundEngine is running.
Idle speedEngine ground
41 YAir conditioner
switchEngine is running.
Both air conditioner switch and blower fan
switch are ``ON''. (Compressor operates.)Approximately 0V
Engine is running.
Air conditioner switch is ``OFF''.BATTERY VOLTAGE
(11 - 14V)
43 GPower steering oil
pressure switchEngine is running.
Steering wheel is being turned.0V
Engine is running.
Steering wheel is not being turned.Approximately 5V
46 GY/LPower supply
(Back-up)Ignition switch ``OFF''
BATTERY VOLTAGE
(11 - 14V)
48 B ECCS groundEngine is running.
Idle speedEngine ground
TROUBLE DIAGNOSIS Ð General DescriptionKA
ECM Terminals and Reference Value
(Cont'd)
EC-72

TERMINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC voltage)
101
103
110
112W/B
W/R
W/L
W/GInjector No. 1
Injector No. 3
Injector No. 2
Injector No. 4Engine is running.
(Warm-up condition)
Idle speedBATTERY VOLTAGE
(11 - 14V)
SEF069U
Engine is running.
Engine speed is 2,000 rpm.BATTERY VOLTAGE
(11 - 14V)
SEF070U
104 W/R Fuel pump relayIgnition switch ``ON''
For 5 seconds after turning ignition switch
``ON''
Engine is running.Approximately 1V
Ignition switch ``ON''
5 seconds after turning ignition switch ``ON''BATTERY VOLTAGE
(11 - 14V)
105 W/LEVAP canister
purge control
solenoid valveEngine is running.
(Warm-up condition)
Idle speedBATTERY VOLTAGE
(11 - 14V)
Engine is running.
(Warm-up condition)
Engine is above 3,800 rpm.Approximately 1V
107
108B/P ECCS groundEngine is running.
Idle speedEngine ground
109 B/W Current returnEngine is running.
Idle speedBATTERY VOLTAGE
(11 - 14V)
113 W/G IACV-AAC valveEngine is running.
Idle speed10 - 13V
Engine is running.
Steering wheel is being turned.Air conditioner is operating.Rear window defogger switch is ``ON''.Lighting switch is ``ON''.5 - 10V
114 RHeated oxygen
sensor heaterEngine is running.
Engine speed is below 3,200 rpm.Approximately 0V
Engine is running.
Engine speed is above 3,200 rpm.BATTERY VOLTAGE
(11 - 14V)
TROUBLE DIAGNOSIS Ð General DescriptionKA
ECM Terminals and Reference Value
(Cont'd)
EC-73

VA
CHECK INPUT SIGNAL CIRCUIT.
1. Turn ignition switch ``OFF''.
2. Disconnect ECM harness connector.
3. Check harness continuity between ter-
minal
V4and ECM terminalsV31,V40
(1É signal), terminalV3and ECM ter-
minals
V22,V30(180É signal).
Continuity should exist.
If OK, check harness for short to
ground and short to power.
OK
cNG
Repair open circuit, short
to ground or short to
power in harness or con-
nectors.
CHECK COMPONENT
(Camshaft position sensor).
Refer to ``COMPONENT INSPECTION''
below.
OK
cNG
Replace camshaft position
sensor.
Disconnect and reconnect harness con-
nectors in the circuit. Then retest.
Trouble is not fixed.
Check ECM pin terminals for damage
and check the connection of ECM har-
ness connector. Reconnect ECM harness
connector and retest.
INSPECTION END
COMPONENT INSPECTION
Camshaft position sensor
1. Start engine.
2. Check voltage between terminals
V3,V4and ground with
DC range.
Condition Terminals Voltage
Engine running at idle
V3and ground Approximately 0.4V*
V4and ground Approximately 2.5V*
*: Average voltage for pulse signal (Actual pulse signal can be confirmed by
oscilloscope.)
If NG, replace distributor assembly with camshaft position
sensor.
3. Visually check signal plate for damage or dust.
SEF077U
SEF750R
AEC148A
.
.
.
.
.
TROUBLE DIAGNOSIS FOR ``CAMSHAFT POSI SEN'' (DTC 11)KA
Camshaft Position Sensor (CMPS) (Cont'd)
EC-88

Mass Air Flow Sensor (MAFS)
COMPONENT DESCRIPTION
The mass air flow sensor is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. It consists of a hot wire that is supplied with electric
current from the ECM. The temperature of the hot wire is con-
trolled by the ECM a certain amount. The heat generated by the
hot wire is reduced as the intake air flows around it. The more
air, the greater the heat loss.
Therefore, the ECM must supply more electric current to the hot
wire as air flow increases. This maintains the temperature of the
hot wire. The ECM detects the air flow by means of this current
change.
CONSULT REFERENCE VALUE IN DATA MONITOR MODE
Remarks: Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
MAS AIR/FL SE
lEngine: After warming uplAir conditioner switch: ``OFF''lShift lever: Neutral positionlNo-loadIdle 1.3 - 1.7V
2,500 rpm 1.7 - 2.1V
ECM TERMINALS AND REFERENCE VALUE
Remarks: Specification data are reference values, and are measured between each terminal andV39(ECCS ground) with a voltme-
ter.
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC voltage)
16 B Mass air flow sensorEngine is running.
(Warm-up condition)
Idle speed1.3 - 1.7V
Engine is running.
(Warm-up condition)
Engine speed is 2,500 rpm.1.7 - 2.1V
17 WMass air flow sensor
groundEngine is running.
(Warm-up condition)
Idle speed0.005 - 0.02V
ON BOARD DIAGNOSIS LOGIC
Diagnostic
Trouble
Code No.Malfunction is detected when ...Check Items
(Possible Cause)
12
lAn excessively high or low voltage from the sensor is
sent to ECM.*lHarness or connectors
(The sensor circuit is open or shorted.)
lMass air flow sensor
*: When this malfunction is detected, the ECM enters fail-safe mode.
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,400 rpm due to the fuel cut.
SEF150U
TROUBLE DIAGNOSIS FOR ``MASS AIR FLOW SEN'' (DTC 12)KA
EC-89

VA
CHECK COMPONENT
(Mass air flow sensor).
Refer to ``COMPONENT INSPECTION''
below.
OK
cNG
Replace mass air flow
sensor.
Disconnect and reconnect harness con-
nectors in the circuits. Then retest.
Trouble is not fixed.
Check ECM pin terminals for damage
and check the connection of ECM har-
ness connector. Reconnect ECM harness
connector and retest.
INSPECTION END
COMPONENT INSPECTION
Mass air flow sensor
1. Turn ignition switch ``ON''.
2. Start engine and warm it up sufficiently.
3. Check voltage between terminal
V1and ground.
Conditions Voltage V
Ignition switch ``ON'' (Engine stopped.) Less than 1.0
Idle (Engine is warmed-up sufficiently.) 1.3 - 1.7
2,500 rpm 1.7 - 2.1
Idle to about 4,000 rpm* 1.3 - 1.7 to Approx. 4.0
*: Check for linear voltage rise in response to increase to about 4,000 rpm in
engine speed.
4. If NG, remove mass air flow sensor from air duct. Check hot
wire for damage or dust.
SEF082U
SEF893J
.
.
.
.
TROUBLE DIAGNOSIS FOR ``MASS AIR FLOW SEN'' (DTC 12)KA
Mass Air Flow Sensor (MAFS) (Cont'd)
EC-94

Ignition Signal
COMPONENT DESCRIPTION
Ignition coil & power transistor (Built into distributor)
The ignition signal from the ECM is sent to and amplified by the
power transistor. The power transistor turns on and off the igni-
tion coil primary circuit. This on-off operation induces the proper
high voltage in the coil secondary circuit.
CONSULT REFERENCE VALUE IN DATA MONITOR MODE
Remarks: Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
IGN TIMING
lEngine: After warming uplAir conditioner switch: ``OFF''lShift lever: Neutral positionlNo-loadIdle 10É BTDC
2,000 rpm More than 25É BTDC
ECM TERMINALS AND REFERENCE VALUE
Remarks: Specification data are reference values, and are measured between each terminal andV39(ECCS ground) with a voltme-
ter.
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC voltage)
1 W/PU Ignition signalEngine is running.
Idle speedApproximately 0.3V
SEF058U
Engine is running.
Engine speed is 2,000 rpm.Approximately 0.7V
SEF059U
SEF128S
TROUBLE DIAGNOSIS FOR ``IGN SIGNAL-PRIMARY'' (DTC 21)KA
EC-99

DIAGNOSTIC PROCEDURE
INSPECTION START
CHECK COOLING SYSTEM FOR LEAK.
Apply pressure to the cooling system with a
tester, and check if the pressure drops.
Testing pressure:
157 kPa (1.57 bar, 1.6 kg/cm
2, 23 psi)
Pressure should not drop.
CAUTION:
Higher than the specified pressure may
cause radiator damage.
OK
cNG
Check the following for leak.
lHoselRadiatorlWater pump
Refer to LC section (``Water
Pump'').
CHECK RADIATOR CAP.
Apply pressure to cap with a tester.
Radiator cap relief pressure:
78 - 98 kPa (0.78 - 0.98 bar, 0.8 - 1.0
kg/cm
2, 11 - 14 psi)
OK
cNG
Replace radiator cap.
CHECK THERMOSTAT.
1. Check valve seating condition at normal
room temperatures.
It should seat tightly.
2. Check valve opening temperature and valve
lift.
Valve opening temperature:
76.5ÉC (170ÉF) [standard]
Valve lift:
More than 10 mm/90ÉC
(0.39 in/194ÉF)
3. Check if valve is closed at 5ÉC (9ÉF) below
valve opening temperature.
For details, refer to LC section (``Thermostat'').
OK
cNG
Replace thermostat.
Check engine coolant temperature sensor.
Refer to ``COMPONENT INSPECTION'',
EC-98.
OK
cNG
Replace engine coolant tem-
perature sensor.
If the cause cannot be isolated, go to ``MAIN
12 CAUSES OF OVERHEATING'' on next
page.
INSPECTION END
Perform FINAL CHECK by the following procedure after
repair is completed.
1. Warm up engine. Run the vehicle for at least 20 minutes. Pay
attention to engine coolant temperature gauge on the instru-
ment panel. If the reading shows an abnormally high
temperature, another part may be malfunctioning.
2. Stop vehicle and let engine idle. Check the intake and exhaust
systems for leaks by listening for noise or visually inspecting
the components.
3. Allow engine to cool and visually check for oil and coolant
leaks. Then, perform ``OVERALL FUNCTION CHECK''.
SLC754AA
SLC755AA
SLC343
.
.
.
.
.
.
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)KA
Overheat (Cont'd)
EC-107

Intake Air Temperature Sensor
The intake air temperature sensor is mounted to the air duct. The
sensor detects intake air temperature and transmits a signal to
the ECM.
The temperature sensing unit uses a thermistor, which is sensi-
tive to the change in temperature. Electrical resistance of the
thermistor decreases in response to the temperature rise.

Intake air temperature
ÉC (ÉF)Resistance kW
þ10 (14) 7.0 - 11.4
20 (68) 2.1 - 2.9
80 (176) 0.27 - 0.38
ON BOARD DIAGNOSIS LOGIC
Diagnostic
Trouble Code
No.Malfunction is detected when ...Check Items
(Possible Cause)
41
lAn excessively low or high voltage from the sensor is
sent to ECM*.lHarness or connectors
(The sensor circuit is open or shorted.)
lIntake air temperature sensor
*: When this malfunction is detected, the ECM enters fail-safe mode.
Engine operating condition in fail-safe modeThe ECM controls on the assumption that the intake temperature
is 20ÉC (68ÉF).
DIAGNOSTIC TROUBLE CODE CONFIRMATION
PROCEDURE
1) Turn ignition switch ``ON''.
2) Select ``DATA MONITOR'' mode with CONSULT.
3) Wait at least 2 seconds.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------OR-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1) Turn ignition switch ``ON'' and wait at least 2 seconds.
2) Turn ignition switch ``OFF'', wait at least 5 seconds and
then turn ``ON''.
3) Perform ``Diagnostic Test Mode II (Self-diagnostic
results)'' with ECM.
SEF086U
SEF012P
SEF002P
TROUBLE DIAGNOSIS FOR ``INT AIR TEMP SEN'' (DTC 41)KA
EC-109