1998 NISSAN PATROL relay

DIAGNOSTIC PROCEDURE
INSPECTION START
CHECK OVERALL FUNCTION.
1. Turn ignition switch ``ON''.
2. Select ``FULL ACCEL SW'' and
``OFF ACCEL SW'' in ``DATA
MONITOR'' mode with CON-
SULT.
3. Check ``FULL ACCEL SW'' and
``OFF ACCEL SW'' signal under
the following conditions.
OFF ACCEL SW:
Accelerator pedal released
ON
Accelerator pedal
depressed OFF
FULL ACCEL SW:
Accelerator pedal released
OFF
Accelerator pedal fully
depressed ON
--------------------------------------------------------------------------------------------------------------------------------------OR--------------------------------------------------------------------------------------------------------------------------------------
1. Turn ignition switch ``ON''.
2. Check voltage between ECM
terminal
V31and ground under
the following conditions.
Voltage:
Accelerator pedal released
Battery voltage
Accelerator pedal
depressed
Approximately 0V
3. Check voltage between ECM
terminal
V32and ground under
the following conditions.
Voltage:
Accelerator pedal released
Approximately 0V
Accelerator pedal fully
depressed
Battery voltage
NG
cOK
INSPECTION END
CHECK POWER SUPPLY.
1. Turn ignition switch ``OFF''.
2. Disconnect accelerator position switch
harness connector.
3. Turn ignition switch ``ON''.
4. Check voltage between terminal
V5
and ground with CONSULT or tester.
Voltage: Battery voltage
OK
cNG
Check the following.
+Harness connectors
M52,F7(LHD mod-
els)
+Harness for open or
short between accelera-
tor position switch and
ECCS relay
+Harness for open or
short between accelera-
tor position switch and
ECM
If NG, repair harness or
connectors.
jA
SEF626S
SEF627S
SEF708V
SEF786V
.
.
.
TROUBLE DIAGNOSES FOR NON-DETECTABLE ITEMS
Accelerator Position Switch (Cont'd)
EC-167

Charge Air Cooler Fan Control
SYSTEM DESCRIPTION
Crankshaft position sensor (TDC)cEngine speed
ECM
cCharge air cooler fan relayCharge air temperature sensorcCharge air temperature
Ignition switch
cStart signal
The ECM controls the charge air cooler fan operation corresponding to the engine speed, the charge air tem-
perature and the start signal. The control system has 2-step control [ON/OFF]. The ECM does not directly drive
the charge air cooler fan. It controls the ON/OFF charge air cooler fan relay, which in turn controls the charge
air cooler fan.
When the charge air temperature is above 67ÉC (153ÉF) and engine speed is more than 1,600 rpm, the charge
air cooler fan operates.
CONSULT REFERENCE VALUE IN DATA MONITOR MODE
Remarks: Speci®cation data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
I/C FAN RLY+When charge air cooler fan is stopped. OFF
+When charge air cooler 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)
8 G/ORCharge air cooler fan
relayEngine is running.
Charge air cooler fan is not operating.BATTERY VOLTAGE
(11 - 14V)
Engine is running.
Charge air cooler fan is operating.0-1V
TROUBLE DIAGNOSES FOR NON-DETECTABLE ITEMS
EC-178

DIAGNOSTIC PROCEDURE
INSPECTION START
CHECK OVERALL FUNCTION.
1. Turn ignition switch ``OFF''.
2. Disconnect charge air temperature sen-
sor harness connector.
3. Connect 150Wresistor to charge air
temperature sensor harness connector.
4. Start engine and keep engine speed at
2,000 rpm.
5. Make sure that charge air cooler fan
operates.
NG
cOK
INSPECTION END
CHECK POWER SUPPLY.
1. Stop engine.
2. Disconnect charge air cooler fan relay.
3. Turn ignition switch ``ON''.
4. Check voltage between terminals
V2,
V5and ground with CONSULT or
tester.
Voltage: Battery voltage
OK
cNG
Check the following.
+Harness connectors
M21,E127
+10A fuse
+15A fuse
+Fuse block
M2
+Harness for open or
short between charge air
cooler fan relay and
fuses
If NG, repair harness or
connectors.
CHECK GROUND CIRCUIT.
1. Turn ignition switch ``OFF''.
2. Disconnect charge air cooler fan motor
harness connector.
3. Check harness continuity between relay
terminal
V3and motor terminalV1,
motor terminal
V2and engine ground.
Continuity should exist.
If OK, check harness for short to
ground and short to power.
OK
cNG
Check the following.
+Harness connectors
E127,M21
+Harness connectors
M50,F5
+Harness for open or
short between charge air
cooler fan relay and
charge air cooler fan
motor
+Harness for open or
short between charge air
cooler fan motor and
engine ground
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
jA
SEF710V
SEF798V
SEF712V
SEF799V
SEF711V
.
.
.
.
TROUBLE DIAGNOSES FOR NON-DETECTABLE ITEMS
Charge Air Cooler Fan Control (Cont'd)
EC-180

jA
CHECK OUTPUT SIGNAL CIRCUIT.
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM
terminal
V8and relay terminalV1.
Continuity should exist.
If OK, check harness for short to
ground and short to power.
OK
cNG
Check the following.
+Harness connectors
E127,M21
+Harness connectors
M52,F7
+Harness for open or
short between ECM and
charge air cooler fan
relay
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
CHECK COMPONENT
(Charge air cooler fan relay).
Refer to ``COMPONENT INSPECTION''
on next page.
OK
cNG
Replace charge air cooler
fan relay.
CHECK COMPONENT
(Charge air cooler fan motor).
Refer to ``COMPONENT INSPECTION''
on next page.
OK
cNG
Replace charge air cooler
fan motor.
Disconnect and reconnect harness con-
nectors in the circuit. Then retest.
Trouble is not ®xed.
Check ECM pin terminals for damage and
check the connection of ECM harness
connector. Reconnect ECM harness con-
nector and retest.
INSPECTION END
SEF800V
SEF801V
.
.
.
.
.
.
TROUBLE DIAGNOSES FOR NON-DETECTABLE ITEMS
Charge Air Cooler Fan Control (Cont'd)
EC-181

COMPONENT INSPECTION
Charge air cooler fan relay
Check continuity between terminalsV3andV5.
Conditions Continuity
12V direct current supply between
terminals
V1andV2Ye s
No current supply No
If NG, replace relay.
Charge air cooler fan motor
1. Disconnect charge air cooler fan motor harness connector.
2. Supply charge air cooler fan motor terminals with battery volt-
age and check operation.
Charge air cooler fan motor should operate.
If NG, replace charge air cooler fan motor.
SEF511P
SEF802V
TROUBLE DIAGNOSES FOR NON-DETECTABLE ITEMS
Charge Air Cooler Fan Control (Cont'd)
EC-182