1998 NISSAN PICK-UP power steering

TROUBLE DIAGNOSIS FOR POWER SUPPLY.... 75
Main Power Supply and Ground Circuit .............. 75
TROUBLE DIAGNOSIS FOR ``CAMSHAFT
POSI SEN'' (DTC 11).............................................. 82
Camshaft Position Sensor (CMPS) ..................... 82
TROUBLE DIAGNOSIS FOR ``MASS AIR
FLOW SEN'' (DTC 12)............................................ 89
Mass Air Flow Sensor (MAFS) ............................ 89
TROUBLE DIAGNOSIS FOR ``COOLANT TEMP
SEN'' (DTC 13)........................................................ 95
Engine Coolant Temperature Sensor (ECTS) ..... 95
TROUBLE DIAGNOSIS FOR ``IGN SIGNAL-
PRIMARY'' (DTC 21)............................................... 99
Ignition Signal ...................................................... 99
TROUBLE DIAGNOSIS FOR ``OVER HEAT''
(DTC 28)................................................................. 106
Overheat ............................................................ 106
TROUBLE DIAGNOSIS FOR ``INT AIR TEMP
SEN'' (DTC 41)...................................................... 109
Intake Air Temperature Sensor ......................... 109
TROUBLE DIAGNOSIS FOR ``THROTTLE POSI
SEN'' (DTC 43)...................................................... 113
Throttle Position Sensor .................................... 113
TROUBLE DIAGNOSIS FOR
NON-DETECTABLE ITEMS.................................. 118
Vehicle Speed Sensor (VSS) ............................ 118
Heated Oxygen Sensor (HO2S)
- LHD Models - .................................................. 123
Heated Oxygen Sensor Heater
- LHD Models - .................................................. 127
Idle Air Control Valve (IACV) - Auxiliary Air
Control (AAC) Valve .......................................... 131
Neutral Position Switch ...................................... 136
EVAP Canister Purge Control Solenoid Valve .. 140
Injector ............................................................... 144
Start Signal ........................................................ 149
Fuel Pump.......................................................... 151
Power Steering Oil Pressure Switch ................. 157
Swirl Control Valve Control Solenoid Valve ...... 161
IACV-FICD Solenoid Valve ................................ 168
MIL & Data Link Connectors ............................. 173
TD
INJECTION SYSTEM............................................ 176
Fuel System ....................................................... 176
INJECTION PUMP................................................. 178
Inspection ........................................................... 178
Removal ............................................................. 178
Installation and Adjustment................................ 180
Disassembly ....................................................... 183
Load Timer Adjustment...................................... 183
Start Q Adjustment Lever .................................. 184
INJECTION NOZZLE............................................. 186Removal and Installation ................................... 186
Disassembly ....................................................... 186
Inspection ........................................................... 187
Cleaning ............................................................. 187
Assembly............................................................ 189
Test and Adjustment .......................................... 189
FUEL SYSTEM CHECK........................................ 191
Bleeding Fuel System ........................................ 191
Bleeding Fuel Filter ............................................ 192
Checking Priming Pump .................................... 192
Checking Fuel Filter Switch ............................... 192
POSITIVE CRANKCASE VENTILATION.............. 193
Description ......................................................... 193
Inspection ........................................................... 193
QUICK-GLOW SYSTEM........................................ 194
Component Parts Location ................................ 194
Circuit Diagram .................................................. 195
Description ......................................................... 196
Wiring Diagram .................................................. 197
Glow Control Unit Circuit Inspection (For Cold
Areas)................................................................. 203
Glow Control Unit Circuit Inspection (Except
for Cold Areas)................................................... 206
Component Inspection ....................................... 208
EGR SYSTEM........................................................ 210
Component Parts Location ................................ 210
Description ......................................................... 211
Operation ........................................................... 212
Wiring Diagram .................................................. 213
System Inspection.............................................. 217
Component Inspection ....................................... 218
SOLENOID TIMER................................................ 220
Description ......................................................... 220
Operation ........................................................... 220
Wiring Diagram .................................................. 222
Inspection ........................................................... 224
FUEL CUT SYSTEM.............................................. 225
Wiring Diagram .................................................. 225
FUEL HEATER SYSTEM...................................... 226
Description ......................................................... 226
Wiring Diagram .................................................. 227
System Inspection.............................................. 228
Component Inspection ....................................... 228
FAST IDLE CONTROL CIRCUIT.......................... 230
Wiring Diagram .................................................. 230
Electrical Components Inspection ..................... 231
KA
SERVICE DATA AND SPECIFICATIONS (SDS). 232
General Specifications ....................................... 232
Inspection and Adjustment ................................ 232

System Chart
Camshaft position sensorc
ECM
(ECCS
control
module)
Mass air flow sensorc
Engine coolant temperature sensorc
Heated oxygen sensor*c
Ignition switchc
Throttle position sensorc
Neutral position switchc
Vehicle speed sensorc
Air conditioner switchc
Battery voltagec
Power steering oil pressure switchc
Intake air temperature sensorc
*: LHD models
Fuel injection &
mixture ratio controlcInjectors
Distributor ignition systemcPower transistor
Idle air control systemcIACV-AAC valve
IACV-FICD solenoid valve
Swirl control valve controlcSwirl control valve control
solenoid valve
EVAP canister controlcEVAP canister purge control
solenoid valve
Fuel pump controlcFuel pump relay
Heated oxygen sensor moni-
tor & on board diagnostic
systemcMalfunction indicator lamp
(On the instrument panel)
Acceleration cut controlcAir conditioner relay
Heated oxygen sensor
heater control*cHeated oxygen sensor
heater
ENGINE AND EMISSION CONTROL OVERALL SYSTEMKA
EC-13

ECCS COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
ItemDIAGNOSTIC TEST MODE
WORK
SUPPORTSELF-DIAG-
NOSTIC
RESULTSDATA
MONITORACTIVE
TESTFUNCTION
TEST
ECCS COMPONENT PARTS
INPUT
Camshaft position sensor X X
Mass air flow sensor X X
Engine coolant temperature
sensorXXX
Heated oxygen sensor X
Vehicle speed sensor X X
Throttle position sensor X X X X
Intake air temperature sensor X X
Ignition switch (start signal) X X
Closed throttle position switch X X
Air conditioner switch X
Neutral position switch X X
Power steering oil pressure
switchXX
Battery voltage X
OUTPUT
Injectors X X X
Power transistor (Ignition timing) XX (Ignition
signal)XXX
IACV-AAC valve X X X X
Air conditioner relay X
Fuel pump relay X X X X
Swirl control valve control
solenoid valveXXX
EVAP canister purge control
solenoid valve*XXX
X: Applicable
* : This item is indicated as ``EGRC SOL/V'' on the CONSULT screen.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONKA
CONSULT (Cont'd)
EC-47

SELF-DIAGNOSTIC MODE
Regarding items detected in ``SELF-DIAG RESULTS'' mode, refer to ``DIAGNOSTIC TROUBLE CODE
INDEX'', EC-1.
DATA MONITOR MODE
Monitored item
[Unit]ECM
input
signalsMain
signalsDescription Remarks
CMPSRPM
(POS) [rpm]
jj
lIndicates the engine speed computed
from the POS signal (1É signal) of the
camshaft position sensor.
MAS AIR/FL SE [V]
jjlThe signal voltage of the mass air flow
sensor is displayed.lWhen the engine is stopped, a certain
value is indicated.
COOLAN TEMP/S
[ÉC] or [ÉF]
jj
lThe engine coolant temperature (deter-
mined by the signal voltage of the engine
coolant temperature sensor) is displayed.lWhen the engine coolant temperature
sensor is open or short-circuited, ECM
enters fail-safe mode. The engine coolant
temperature determined by the ECM is
displayed.
O2 SEN [V]
jjlThe signal voltage of the heated oxygen
sensor is displayed.lLHD models only
M/R F/C MNT
[RICH/LEAN]
jj
lDisplay of heated oxygen sensor signal
during air-fuel ratio feedback control:
RICH ... means the mixture became
``rich'', and control is being affected
toward a leaner mixture.
LEAN ... means the mixture became
``lean'', and control is being affected
toward a rich mixture.lAfter turning ON the ignition switch,
``RICH'' is displayed until air-fuel mixture
ratio feedback control begins.
lWhen the air-fuel ratio feedback is
clamped, the value just before the clamp-
ing is displayed continuously.
lLHD models only
VHCL SPEED SE
[km/h] or [mph]
jjlThe vehicle speed computed from the
vehicle speed sensor signal is displayed.
BATTERY VOLT [V]
jjlThe power supply voltage of ECM is dis-
played.
THRTL POS SEN [V]
jjlThe throttle position sensor signal volt-
age is displayed.
INT/A TEMP SE
[ÉC] or [ÉF]
j
lThe intake air temperature (determined
by the signal voltage of the intake air
temperature sensor) is indicated.
START SIGNAL
[ON/OFF]
jjlIndicates [ON/OFF] condition from the
starter signal.lAfter starting the engine, [OFF] is
displayed regardless of the starter signal.
CLSD THL/POSI
[ON/OFF]
jj
lIndicates [ON/OFF] condition from the
throttle position sensor signal.
AIR COND SIG
[ON/OFF]
jj
lIndicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
P/N POSI SW
[ON/OFF]
jj
lIndicates [ON/OFF] condition from the
park/neutral position switch signal.
PW/ST SIGNAL
[ON/OFF]
jj
l[ON/OFF] condition of the power steering
oil pressure switch determined by the
power steering oil pressure signal is indi-
cated.
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONKA
CONSULT (Cont'd)
EC-48

FUNCTION TEST
ITEMCONDITION JUDGEMENT CHECK ITEM (REMEDY)
PW/ST SIGNAL
CIRCUIT
lIgnition switch: ON
(Engine running)
lPower steering oil pressure switch
circuit is tested when steering
wheel is rotated fully and then set
to a straight line running position.Locked position ONlHarness and connector
lPower steering oil pressure switch
lPower steering oil pump
Neutral position OFF
SWRL CONT S/V
CIRCUIT
lIgnition switch: ON
(Engine stopped)
lSwirl control valve control sole-
noid valve circuit is tested by
checking solenoid valve operating
sound.The solenoid valve makes an
operating sound every 3 sec-
onds.
lHarness and connector
lSolenoid valve
lSwirl control valve
lVacuum hose
VEHICLE SPEED
SEN CKT
lVehicle speed sensor circuit is
tested when vehicle is running at
a speed of 10 km/h (6 MPH) or
higher.Vehicle speed sensor input
signal is greater than 4 km/h
(2 MPH).lHarness and connector
lVehicle speed sensor
lSpeedometer
IGN TIMING ADJ
lAfter warming up, idle the engine.
lIgnition timing is checked by read-
ing ignition timing with a timing
light and checking whether it
agrees with specifications.The timing light indicates the
same value on the screen.
lAdjust ignition timing (by moving
camshaft position sensor or
distributor)
lCamshaft position sensor drive
mechanism
MIXTURE RATIO
TEST
lAir-fuel ratio feedback circuit
(injection system, ignition system,
vacuum system, etc.) is tested by
examining the heated oxygen
sensor output at 2,000 rpm under
non-loaded state.Heated oxygen sensor
COUNT: More than 5 times
during 10 seconds
lINJECTION SYS (Injector, fuel
pressure regulator, harness or
connector)
lIGNITION SYS (Spark plug,
ignition coil, power transistor
harness or connector)
lVACUUM SYS (Intake air leaks)
lHeated oxygen sensor circuit
lHeated oxygen sensor operation
lFuel pressure high or low
lMass air flow sensor
POWER BALANCE
lAfter warming up, idle the engine.
lInjector operation of each cylinder
is stopped one after another, and
resultant change in engine rota-
tion is examined to evaluate com-
bustion of each cylinder. (This is
only displayed for models where a
sequential multiport fuel injection
system is used.)Difference in engine speed is
greater than 25 rpm before
and after cutting off the injec-
tor of each cylinder.lInjector circuit (Injector, harness
or connector)
lIgnition circuit (Spark plug, igni-
tion coil, power transistor harness
or connector)
lCompression
lValve timing
IACV-AAC/V
SYSTEM
lAfter warming up, idle the engine.
lIACV-AAC valve system is tested
by detecting change in engine
speed when IACV-AAC valve
opening is changed to 0%, 20%
and 80%.Difference in engine speed is
greater than 150 rpm between
when valve opening is at 80%
and at 20%.
lHarness and connector
lIACV-AAC valve
lAir passage restriction between
air inlet and IACV-AAC valve
lIAS (Idle adjusting screw) adjust-
ment
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONKA
CONSULT (Cont'd)
EC-52

Symptom Matrix Chart
SYMPTOM
Reference 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)
OVERCOOLS
OVERCHARGING
Warranty Symptom Code AA AB AC AD AE AF AG AH AJ AK AL AM HA 1P 1X
Basic engine control system
Fuel Fuel pump circuitllljlljjjEC-151
Fuel pressure regulator system
llljljlljlEC-22
Injector circuit
llljlll lEC-144
Evaporative emission systemjjjj
ljjjj jEC-19
Air Positive crankcase ventilation systemjjjj
ljjjj jjEC-21
Incorrect idle speed adjustmentjj jjjj jEC-25
Swirl control valve circuitjj
lEC-161
IACV-AAC valve circuit
llljllllljjEC-131
IACV-FICD solenoid valve circuitjjjjjjjjj jEC-168
Ignition Incorrect ignition timing adjustmentjj
lll ll lEC-25
Ignition circuit
lllll ll lEC-99
EVAP EVAP canister purge control solenoid
valve circuit
ljjjj j jEC-140
Main power supply and ground circuit
llljj jj jj jEC-75
Air conditioner circuitjjjjjjjjj j jHA section
ECCS system
ECCS Camshaft position sensor circuitllllljj jEC-82
Mass air flow sensor circuit
lllll ljjEC-89
Heated oxygen sensor circuit
lljlljlEC-123, 127
Engine coolant temperature sensor circuit
llljllljjlEC-95
Throttle position sensor circuit
ll lllll lEC-113
Incorrect throttle position sensor adjust-
ment
ljjljjljEC-58
Vehicle speed sensor circuitjj j jEC-118
ECMjjjjjjjjjjjEC-61
Start signal circuitjEC-149
Neutral position switch circuitjjjj jEC-136
Power steering oil pressure switch circuitjjjEC-157
l; High Possibility Item
j; Low Possibility Item(continued on next page)
TROUBLE DIAGNOSIS Ð General DescriptionKA
EC-62

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

Idle Air Control Valve (IACV) Ð Auxiliary Air
Control (AAC) Valve
SYSTEM DESCRIPTION
Camshaft position sensorcEngine speed
ECM
(ECCS
control
module)
cIACV-AAC valve
Mass air flow sensorcAmount of intake air
Engine coolant temperature sensor
cEngine coolant temperature
Ignition switch
cStart signal
Throttle position sensor
cThrottle position
Neutral position switch
cNeutral position
Air conditioner switch
cAir conditioner operation
Power steering oil pressure switch
cPower steering load signal
Battery
cBattery voltage
Vehicle speed sensor
cVehicle speed
This system automatically controls engine idle speed to a specified level. Idle speed is controlled through
fine adjustment of the amount of air which by-passes the throttle valve via IACV-AAC valve. The IACV-AAC
valve repeats ON/OFF operation according to the signal sent from the ECM. The camshaft position sensor
detects the actual engine speed and sends a signal to the ECM. The ECM then controls the ON/OFF time
of the IACV-AAC valve so that engine speed coincides with the target value memorized in ECM. The tar-
get engine speed is the lowest speed at which the engine can operate steadily. The optimum value stored
in the ECM is determined by taking into consideration various engine conditions, such as during warm up,
deceleration, and engine load (air conditioner and power steering operation).
COMPONENT DESCRIPTION
IACV-ACC valve
The IACV-AAC valve is moved by ON/OFF pulses from the
ECM. The longer the ON pulse, the greater the amount of air that
will flow through the valve. The more air that flows through the
valve, the higher the idle speed.
SEF040E
TROUBLE DIAGNOSIS FOR NON-DETECTABLE ITEMSKA
EC-131