1998 NISSAN PATROL engine

ON BOARD DIAGNOSIS LOGIC
Diagnostic
Trouble Code
No.Malfunction is detected when ....Check Items
(Possible cause)
21+Injection timing feedback system does not operate
properly. (This system consists essentially of ECM,
injection timing control valve and needle lift sensor.)+Harness or connectors
[Injection timing control valve, needle lift sensor,
crankshaft position sensor (TDC) circuits]
+Injection timing control valve
+Needle lift sensor
+Crankshaft position sensor (TDC)
+Air in fuel line
DIAGNOSTIC TROUBLE CODE CONFIRMATION
PROCEDURE
Note: If both DTC 21 and 34 or 47 are displayed, perform
TROUBLE DIAGNOSIS FOR DTC 34 or 47. (See EC-126
or EC-144.)
1) Turn ignition switch ``ON'' and select ``DATA MONITOR''
mode with CONSULT.
2) Start engine and warm it up to normal operating tem-
perature.
3) Run engine for 2 seconds at 3,000 rpm. Return engine
speed to idle, then increase to 3,000 rpm under no load.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------OR-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1) Start engine and warm it up to normal operating tem-
perature.
2) Run engine for 2 seconds at 3,000 rpm. Return engine
speed to idle, then increase to 3,000 rpm under no load.
3) Turn ignition switch ``OFF'', wait at least 5 seconds and
then turn ``ON''.
4) Perform ``Diagnostic Test Mode II (Self-diagnostic
results)'' with ECM.
Note: If a malfunction occurs intermittently, conduct suitable
driving pattern for 10 minutes. This makes it possible to
determine DTC.
SEF751V
TROUBLE DIAGNOSIS FOR ``F/INJ TIMG F/B'' (DTC 21)
Injection Timing Control Valve (Cont'd)
EC-102

Accelerator Switch (F/C)
The accelerator switch is installed to the accelerator pedal assem-
bly. The switch senses accelerator position and sends an ON-OFF
signal to the ECM. The ECM uses the signal to control the fuel cut
operation at deceleration for better fuel efficiency.
CONSULT REFERENCE VALUE IN DATA MONITOR MODE
Remarks: Speci®cation data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SW (FC)+Ignition switch: ON
(Engine stopped)Accelerator pedal: released CLOSE
Accelerator pedal: slightly open OPEN
DECELER F/CUT+Engine: After warming upIdle OFF
When accelerator pedal is
released quickly with engine
speed at 3,000 rpm or more.ON
ECM TERMINALS AND REFERENCE VALUE
Remarks: Speci®cation data are reference values and are measured between each terminal andV43(ECCS
ground) with a voltmeter.
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse
Signal)
29 R/L Accelerator switch (F/C)Ignition switch ``ON''
Accelerator pedal fully releasedBATTERY VOLTAGE
(11 - 14V)
Ignition switch ``ON''
Accelerator pedal depressedApproximately 0V
ON BOARD DIAGNOSIS LOGIC
Diagnostic
Trouble Code
No.Malfunction is detected when ....Check Items
(Possible cause)
23+The OFF signal (short) is sent to the ECM for a cer-
tain period of time even when the accelerator pedal is
not being depressed.+Harness or connectors
(The switch circuit is shorted.)
+Accelerator switch (F/C)
SEF687V
TROUBLE DIAGNOSIS FOR ``ACCEL POS SW (F/C)'' (DTC 23)
EC-106

DIAGNOSTIC PROCEDURE
INSPECTION START
CHECK OVERALL FUNCTION.1. Turn ignition switch ``ON''.
2. Check ``ACCEL SW (F/C)'' in
``DATA MONITOR'' mode with
CONSULT.
Accelerator pedal released:
OFF
Accelerator pedal depressed:
ON
--------------------------------------------------------------------------------------------------------------------------------------OR--------------------------------------------------------------------------------------------------------------------------------------
1. Turn ignition switch ``ON''.
2. Check voltage between ECM
terminal
V29and ground.
Voltage:
Accelerator pedal released
Battery voltage
Accelerator pedal depressed
Approximately 0V
NG
cOK
INSPECTION END
CHECK GROUND CIRCUIT.
1. Turn ignition switch ``OFF''.
2. Loosen and retighten engine ground
screws.
3. Disconnect accelerator switch (F/C) har-
ness connector.
4. Check harness continuity between termi-
nal
V3and engine ground.
Continuity should exist.
If OK, check harness for short to ground
and short to power.
OK
cNG
Check the following.
+Harness connectors
M51,F6(RHD mod-
els)
+Joint connector
F18+Harness for open or
short between accelera-
tor switch (F/C) and
engine ground
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
CHECK INPUT SIGNAL CIRCUIT.
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM
terminal
V29and terminalV1.
Continuity should exist.
If OK, check harness for short to ground
and short to power.
OK
cNG
Check the following.
+Harness connectors
F6,M51(RHD mod-
els)
+Harness for open or short
between ECM and accel-
erator switch (F/C)
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
CHECK COMPONENT
[Accelerator switch (F/C)].
Refer to ``COMPONENT INSPECTION''
on next page.
OK
cNG
Replace accelerator pedal
assembly.
Disconnect and reconnect harness connec-
tors in the circuit. Then retest.
Trouble is not ®xed.
Check ECM pin terminals for damage and
check the connection of ECM harness con-
nector. Reconnect ECM harness connector
and retest.
INSPECTION END
SEF688V
SEF589S
SEF590S
SEF591S
SEF592S
.
.
.
.
.
.
.
TROUBLE DIAGNOSIS FOR ``ACCEL POS SW (F/C)'' (DTC 23)
Accelerator Switch (F/C) (Cont'd)
EC-109

Engine Control Module (ECM)-ECCS-D Control
Module
The ECM consists of a microcomputer and connectors for signal
input and output and for power supply. The unit controls the engine.
Diagnostic
Trouble Code
No.Malfunction is detected when ....Check Item
(Possible Cause)
27, 31+ECM calculation function is malfunctioning.+ECM
(ECCS-D control module)
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''.
2) Wait at least 2 seconds.
3) Turn ignition switch ``OFF'', wait at least 5 seconds and
then turn ``ON''.
4) Perform ``Diagnostic Test Mode II (Self-diagnostic
results)'' with ECM.
SEC220B
SEF748V
TROUBLE DIAGNOSIS FOR ``ECM 1'' (DTC 27), ``ECM 2'' (DTC 31)
EC-111

DIAGNOSTIC PROCEDURE
INSPECTION START
1) Turn ignition switch ``ON''.
2) Select ``SELF DIAG RESULTS''
mode with CONSULT.
3) Touch ``ERASE''.
--------------------------------------------------------------------------------------------------------------------------------------OR--------------------------------------------------------------------------------------------------------------------------------------
1) Turn ignition switch ``ON''.
2) Erase the Diagnostic Test Mode
II (Self-diagnostic results)
memory.
PERFORM SELF-DIAGNOSIS.
Select ``SELF DIAG RESULTS''
mode with CONSULT.
--------------------------------------------------------------------------------------------------------------------------------------OR--------------------------------------------------------------------------------------------------------------------------------------
PERFORM ``Diagnostic Test Mode
II'' (SELF-DIAGNOSTIC
RESULTS).
Is the DTC 27, 31 displayed again?
No
cYe s
Replace ECM.
INSPECTION END
.
.
.
.
TROUBLE DIAGNOSIS FOR ``ECM 1'' (DTC 27), ``ECM 2'' (DTC 31)
Engine Control Module (ECM)-ECCS-D Control
Module (Cont'd)
EC-112

Cooling Fan (Overheat)
SYSTEM DESCRIPTION
Vehicle speed sensorcVehicle speed
ECM
(ECCS-D
control
mod-
ule)
cCooling fan
relayEngine coolant temperature sensorcEngine coolant temperature
Air conditioner switch
cAir conditioner ``ON'' signal
The ECM controls the cooling fan corresponding to the vehicle speed, engine coolant temperature, air condi-
tioner system pressure and air conditioner ON signal. The control system has 2-step control [ON/OFF].
Operation
CONSULT REFERENCE VALUE IN DATA MONITOR MODE
Remarks: Speci®cation data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
AIR COND SIG+Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
COOLING FAN+When cooling fan is stopped. OFF
+When cooling fan operates. ON
ECM TERMINALS AND REFERENCE VALUE
Remarks: Speci®cation data are reference values and are measured between each terminal andV43(ECCS
ground) with a voltmeter.
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse
Signal)
14 L Cooling fan relayEngine is running.
Cooling fan is not operating.BATTERY VOLTAGE
(11 - 14V)
Engine is running.
Cooling fan is operating.0-1V
SEF757V
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)
EC-113

TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse
Signal)
15 Y/L Air conditioner relayEngine is running.
Air conditioner switch is ``OFF''.BATTERY VOLTAGE
(11 - 14V)
Engine is running.
Both air conditioner switch and blower fan
switch are ``ON''.
(Compressor is operating.)0-1V
ON BOARD DIAGNOSIS LOGIC
This diagnosis continuously monitors the engine coolant temperature.
If the cooling fan or another component in the cooling system malfunctions, engine coolant temperature will
rise.
When the engine coolant temperature reaches an abnormally high temperature condition, a malfunction is
indicated.
Diagnostic Trouble
Code No.Malfunction is detected when ...Check Items
(Possible Cause)
28+Cooling fan does not operate properly (Overheat).
+Cooling fan system does not operate properly (Over-
heat).
+Engine coolant was not added to the system using
the proper ®lling method.+Harness or connectors
(The cooling fan circuit is open or shorted.)
+Cooling fan
+Radiator hose
+Radiator
+Radiator cap
+Water pump
+Thermostat
+Fan belt
+Engine coolant temperature sensor
For more information, refer to ``MAIN 12
CAUSES OF OVERHEATING'', EC-120.
CAUTION:
When a malfunction is indicated, be sure to replace the coolant following the procedure in the MA
section (``Changing Engine Coolant'', ``ENGINE MAINTENANCE''). Also, replace the engine oil.
a. Fill radiator with coolant up to speci®ed level with a ®lling speed of 2 liters per minute. Be sure to
use coolant with the proper mixture ratio. Refer to MA section (``Anti-freeze Coolant Mixture Ratio'',
``RECOMMENDED FLUIDS AND LUBRICANTS'').
b. After re®lling coolant, run engine to ensure that no water-¯ow noise is emitted.
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)
Cooling Fan (Overheat) (Cont'd)
EC-114

OVERALL FUNCTION CHECK
Use this procedure to check the overall function of the cooling fan.
During this check, a DTC might not be con®rmed.
WARNING:
Never remove the radiator cap when the engine is hot. Serious
burns could be caused by high pressure ¯uid escaping from
the radiator.
Wrap a thick cloth around the cap. Carefully remove the cap
by turning it a quarter turn to allow built-up pressure to
escape. Then turn the cap all the way off.
1) Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to ``DIAG-
NOSTIC PROCEDURE'', EC-117.
2) Con®rm whether customer ®lled the coolant or not. If customer
®lled the coolant, skip the following steps and go to ``DIAGNOS-
TIC PROCEDURE'', EC-117.
3) Turn ignition switch ``ON''.
4) Perform ``COOLING FAN'' in ``ACTIVE TEST'' mode with
CONSULT and make sure that cooling fan operates
when touching ``ON''.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------OR-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
3) Disconnect engine coolant temperature sensor harness
connector.
4) Connect 150Wresistor to engine coolant temperature
sensor harness connector.
5) Start engine and make sure that cooling fan operates.
Be careful not to overheat engine.
AEC640
SEF758V
SEF979S
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)
Cooling Fan (Overheat) (Cont'd)
EC-115