1998 NISSAN PATROL Engine Control Workshop Manual

TEC430
TROUBLE DIAGNOSIS FOR ``F/INJ TIMG F/B'' (DTC 21)
Injection Timing Control Valve (Cont'd)
EC-103

DIAGNOSTIC PROCEDURE
INSPECTION START
CHECK FOR AIR IN FUEL FILTER.
1. Move priming pump up and down to
purge air from fuel ®lter.
2. Perform ``DIAGNOSTIC TROUBLE
CODE CONFIRMATION PROCE-
DURE''.
NG
cOK
INSPECTION END
CHECK POWER SUPPLY.
1. Turn ignition switch ``OFF''.
2. Disconnect injection timing control valve
harness connector.
3. Turn ignition switch ``ON''.
4. Check harness continuity between ter-
minal
V2and ground with CONSULT or
tester.
Voltage: Battery voltage
OK
cNG
Check the following.
+Harness connectors
M51,F6
+Electronic fuel injection
pump harness connector
F3
+10A fuse
+Harness for open or
short between injection
timing control valve and
fuse
If NG, repair harness or
connectors.
CHECK OUTPUT SIGNAL CIRCUIT.
1. Turn ignition switch ``OFF''.
2. Disconnect ECM harness connector.
3. Check harness continuity between ter-
minal
V1and ECM terminals104,
11 0.
Continuity should exist.
If OK, check harness for short to
ground and short to power.
OK
cNG
Check the following.
+Electronic fuel injection
pump harness connector
F3
+Harness for open or
short between injection
timing control valve and
ECM
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
CHECK COMPONENT
(Injection timing control valve).
Refer to ``COMPONENT INSPECTION''
on next page.
OK
cNG
Replace injection timing
control valve.
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
SEF670V
SEF685V
SEF754V
SEF755V
.
.
.
.
.
.
.
TROUBLE DIAGNOSIS FOR ``F/INJ TIMG F/B'' (DTC 21)
Injection Timing Control Valve (Cont'd)
EC-104

COMPONENT INSPECTION
Injection timing control valve
1. Reconnect injection timing control valve harness connector.
2. Disconnect electronic fuel injection pump harness connector.
3. Check resistance between terminals
V3andV7.
Resistance: Approximately 11W[at 20ÉC (68ÉF)]
If NG, replace injection timing control valve.
SEF686V
TROUBLE DIAGNOSIS FOR ``F/INJ TIMG F/B'' (DTC 21)
Injection Timing Control Valve (Cont'd)
EC-105

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 TROUBLE CODE CONFIRMATION
PROCEDURE
1) Turn ignition switch ``ON'' and select ``DATA MONITOR''
mode with CONSULT.
2) Depress and release accelerator pedal once for 15 sec-
onds.
3) Repeat step 2 for 26 times.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------OR-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1) Turn ignition switch ``ON''.
2) Depress and release accelerator pedal once for 15 sec-
onds.
3) Repeat step 2 for 26 times.
4) Turn ignition switch ``OFF'', wait at least 5 seconds and
then turn ``ON''.
5) Perform ``Diagnostic Test Mode II (Self-diagnostic
results)'' with ECM.
SEF756V
TROUBLE DIAGNOSIS FOR ``ACCEL POS SW (F/C)'' (DTC 23)
Accelerator Switch (F/C) (Cont'd)
EC-107

TEC431
TROUBLE DIAGNOSIS FOR ``ACCEL POS SW (F/C)'' (DTC 23)
Accelerator Switch (F/C) (Cont'd)
EC-108

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
.
.
.
.
.
.
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TROUBLE DIAGNOSIS FOR ``ACCEL POS SW (F/C)'' (DTC 23)
Accelerator Switch (F/C) (Cont'd)
EC-109

COMPONENT INSPECTION
Accelerator switch (F/C)
1. Disconnect accelerator switch (F/C) harness connector.
2. Check continuity between terminals
V1andV3.
Conditions Continuity
Accelerator pedal released No
Accelerator pedal depressed Yes
If NG, replace accelerator pedal assembly.
SEF689V
TROUBLE DIAGNOSIS FOR ``ACCEL POS SW (F/C)'' (DTC 23)
Accelerator Switch (F/C) (Cont'd)
EC-110