Page 582 of 1833

22 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors F120, M812 (LHD models)
I Fuse block (J/B) connector F48 (LHD models)
I Fuse block (J/B) connector M756 (RHD models)
I 10A fuse
I Resistor
I Harness for open or short between ECM and fuse
ERepair open circuit or short to ground or short to power in harness or connectors.
23 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº EC-78.
OK or NG
OK EReplace engine oil pressure switch-2.
NG ERepair harness or connectors.
24 OVERALL FUNCTION CHECK-V
1. Turn ignition switch ªOFFº.
2. Disconnect engine oil pressure switch-2 harness connector.
3. Start engine and warm it up to normal operating temperature.
4. Keep engine speed between 3,600 to 4,200 rpm at least 30 seconds.
5. Check oil pressure warning lamp illumination.
Oil pressure warning lamp should not illuminate.
OK or NG
OK EGO TO 25.
NG EReplace oil pressure switch-2.
25 DETECT MALFUNCTIONING PART
Check the following.
IHarness for short to ground between ECM and engine oil pressure switch-2
I Harness for short to ground between ECM and fuse block
ERepair short to ground in harness or connectors.
ENGINE OIL PRESSURE SWITCHZD30DDTi
Diagnostic Procedure (Cont'd)
EC-307
http://vnx.su/
Page 612 of 1833

Inspection (No.2-4nozzle)
Thoroughly clean all disassembled parts with fresh kerosene or
solvent.
IIf nozzle needle is damaged or fused, replace nozzle assem-
bly with a new one.
I If end of nozzle needle is seized or excessively discolored,
replace nozzle assembly.
I Check nozzle body and distance piece for proper contact. If
excessively worn or damaged, replace nozzle assembly or dis-
tance piece.
I Check nozzle spring for excessive wear or damage. If exces-
sively worn or damaged, replace it with a new spring.
I Check distance piece and nozzle holder for proper contact. If
excessively worn or damaged, replace nozzle holder assembly.
Cleaning (No.2-4nozzle)
a. Do not touch the nozzle mating surface with your fingers.
b. To wash the nozzles, use a wooden stick and brass brush
with clean diesel fuel.
1. Remove any carbon from exterior of nozzle body (except wrap- ping angle portion) by using Tool.
2. Clean oil sump of nozzle body using Tool.
3. Clean nozzle seat by using Tool.
Take extra precautions when performing this job, since nozzle
efficiency depends greatly on a good nozzle seat.
SEF830
YEC231A
SEF832
INJECTION NOZZLETD27Ti
EC-337
http://vnx.su/
Page 625 of 1833
CONSULT-II
CONSULT-II INSPECTION PROCEDURE
1. Turn off ignition switch.
2. Connect ªCONSULT-IIº to data link connector for CONSULT-II.(Data link connector for CONSULT-II is located behind the fuse
box cover.)
3. Turn on ignition switch.
4. Touch ªSTARTº.
5. Touch ªENGINEº.
6. Perform each diagnostic test mode according to each service procedure.
For further information, see the CONSULT-II Operation Manual.
NRS122
YEC696A
YEC697A
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONTD27Ti
EC-350
http://vnx.su/
Page 651 of 1833

Diagnostic Procedure
INSPECTION START
Start engine.
Is engine running?
Ye s
ENoCHECK POWER SUPPLY-I.
1. Turn ignition switch to ªONº posi-
tion.
2. Check voltage between ECM connector terminal
507and
engine ground with
CONSULT-II or voltage tester.
Voltage: Battery voltage
If NG, check the following:
I 10A fuse
I Harness for open or short-circuit
between ECM and ignition switch
If NG, replace 10A fuse or repair
harness or connectors.
OK
Go to q
BªCHECK GROUND CIR-
CUITº.
CHECK POWER SUPPLY-II.
1. Stop engine.
2. Check voltage between ECM connector terminal
325and
engine ground with CON-
SULT-II or voltage tester.
Voltage: Battery voltage
OK
ENG Check the following:
IECM relay
I 20A fuse
I Harness for open or short-circuit
between ECM and battery
I Harness connectors M787, F66
(LHD models)
I Battery connection and charge
If NG, replace fuse or charge bat-
tery or repair harness or connec-
tors.
qA
NEF642
YEC283A
MEC946D
MEC943D
H
H
H
H
TROUBLE DIAGNOSIS FOR POWER SUPPLYTD27Ti
EC-376
http://vnx.su/
Page 652 of 1833

qA
CHECK POWER SUPPLY-III.
1. Turn ignition switch to ªONº positionand then to ªLOCKº position.
2. Check voltage between ECM connector terminals
107,108,109and engine
ground with CONSULT-II or tester.
Voltage: After turning ignition switch to
ªLOCKº position, battery voltage
will exist for a few seconds, then
drop to approximately 0V.
NG
EOK Go toqBªCHECK
GROUND CIRCUITº.
Case-1: Battery voltage does not exist.
Case-2: Battery voltage exists for more than a few
seconds.
Case-1 Case-2
EGo toªCHECK ECM
RELAYº.
CHECK HARNESS CONTINUITY
BETWEEN ECM RELAY AND ECM.
1. Disconnect ECM harness connector.
2. Disconnect ECM relay harness connec- tor.
3. Check harness continuity between ECM connector terminals
325and
ECM relay connector terminal q
2, and
ECM connector terminals
107,108,
109and ECM relay connector termi-
nal q
5. Refer to wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG Check the following:
IHarness connectors
M787,F66(LHD mod-
els)
I Harness for open or
short-circuit between
ECM relay connector
and ECM connector.
If NG, repair harness or
connectors.
CHECK VOLTAGE BETWEEN ECCS
RELAY AND ENGINE GROUND.
Check voltage between ECM relay con-
nector terminals q
1,q3and engine ground
with CONSULT-II or tester.
Voltage: Battery voltage
OK
ENG Check the following:
I20A fuse
I Fuse box and battery
connections
I Harness for open or
short-circuit between
ECM relay and battery
If NG, replace fuse or
repair harness or connec-
tors.
CHECK ECM RELAY.
1. Remove ECM relay.
2. Apply 12V direct current between relay terminals q
1andq2.
3. Check continuity between relay termi- nals q
3andq5.
12V ( q
1-q2) applied:
Continuity exists.
No voltage applied: No continuity
OK
ENG Replace ECM relay.
qB
MEC944D
MEC945D
NEF350
H
H
H
H
H
TROUBLE DIAGNOSIS FOR POWER SUPPLYTD27Ti
Diagnostic Procedure (Cont'd)
EC-377
http://vnx.su/
Page 657 of 1833

Diagnostic Procedure
INSPECTION START
CHECK POWER SUPPLY.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect mass air flow sensor har- ness connector.
3. Turn ignition switch to ªONº position.
4. Check voltage between mass air flow sensor connector terminal q
2and
engine ground with CONSULT-II or
tester.
Voltage: Battery positive voltage
OK
ENG Check the following:
I10A fuse
I Harness continuity
between ECM relay (coil
and load side) connector
and battery supply
I Harness connectors
F100,M775(RHD mod-
els)
I Harness continuity
between ECM relay con-
nector and Mass Air
Flow Sensor Connector.
If NG, replace 10A fuse or
repair or replace harness
or connectors.
CHECK GROUND CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect ECM harness connector.
3. Loosen and retighten engine ground screws.
4. Check harness continuity between mass air flow sensor harness connec-
tor terminal q
3and ECM connector ter-
minal218. Refer to wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG Check the following.
IHarness connectors
F100,M775(RHD mod-
els)
I Harness continuity
between mass air flow
sensor and ECM
If NG, repair or replace
harness or connectors.
CHECK INPUT SIGNAL CIRCUIT.
Check harness continuity between mass
air flow sensor connector terminal q
4and
ECM connector terminal223. Refer to
wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG Check the following.
IHarness connectors
F100,M775(RHD mod-
els)
I Harness continuity
between mass air flow
sensor and ECM
If NG, repair or replace
harness or connectors.
CHECK INPUT SIGNAL CIRCUIT.
Check harness continuity between mass
air flow sensor connector terminal q
5and
ECM connector terminal224. Refer to
wiring diagram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG Check the following.
IHarness connectors
F100,M775(RHD mod-
els)
I Harness continuity
between mass air flow
sensor and ECM
If NG, repair or replace
harness or connectors.
CHECK COMPONENT
(Mass air flow sensor).
Refer to ªCOMPONENT INSPECTIONº,
EC-383.
OK
ENG Replace mass air flow sen-
sor.
qA
NEF664
NEF591
NEF352
H
H
H
H
H
H
DTC P0100 MASS AIR FLOW SENTD27Ti
EC-382
http://vnx.su/
Page 668 of 1833

qA
CHECK INPUT SIGNAL CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect accelerator work unit har- ness connector and ECM harness con-
nector.
3. Check harness continuity between accelerator work unit terminal q
3and
ECM terminal
435. Refer to wiring
diagram.
Continuity should exist.
Check harness for short-circuit.
OK
ENG Check the following:
I10A fuse in fuse box
I 75A fusible link in fusible
link box
I Harness continuity
between ECM relay and
battery positive supply
I Harness for open or
short-circuit between
ECM relay and accelera-
tor position switch.
If NG, repair harness or
connectors.
CHECK GROUND CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect ECM harness connector.
3. Check harness continuity between accelerator work unit connector termi-
nal q
1and ECM connector terminal
426. Refer to wiring diagram.
Continuity should exist.
If OK; check harness for short-circuit.
If OK, re-connect harness connectors.
OK
ENG Repair harness or connec-
tors.
CHECK COMPONENT.
(Accelerator position switch.)
Refer to ªCOMPONENT INSPECTIONº on
page EC-394.
OK
ENGReplace accelerator pedal.
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 harness
connector. Reconnect ECM harness con-
nector and retest.
INSPECTION END
SEF628S
H
H
H
H
H
H
DTC P0120 ACCEL POS SENSORTD27Ti
Diagnostic Procedure (Cont'd)
EC-393
http://vnx.su/
Page 681 of 1833

Diagnostic Procedure
INSPECTION START
CHECK FOR AIR IN FUEL FILTER.
1. Move priming pump up and down topurge air from fuel filter.
2. Perform ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº.
CHECK POWER SUPPLY.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect TVC and shut-off (injection timing control valve) harness connec-
tor.
3. Turn ignition switch to ªONº position.
4. Check voltage between TVC and shut- off (injection timing control valve) con-
nector terminal q
9and engine ground
with CONSULT-II or tester.
Voltage: Battery voltage
OK
ENG Check the following:
IHarness connector
M787,F66
I20A fuse
I ECM relay
I Harness for open or
short-circuit between
TVC and shut-off (injec-
tion timing control valve)
harness connector and
fuse box.
If NG, replace 20A fuse or
ECM relay, harness or con-
nectors.
CHECK OUTPUT SIGNAL CIRCUIT.
1. Turn ignition switch to ªLOCKº position.
2. Disconnect ECM harness connector.
3. Check harness continuity between TVC and shut-off (injection timing control
valve) connector terminal q
8and ECM
terminals
202. Refer to wiring dia-
gram.
Continuity should exist.
If OK, check harness for short-circuit.
OK
ENG Check the following:
IHarness for open or
short-circuit between
TVC and shut-off (injec-
tion timing control valve)
and ECM
If NG, repair harness or
connectors.
CHECK GROUND CIRCUIT.
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM connector terminal
349and TVC
and shut-off (injection timing control
valve) connector terminal q
10. Refer to
wiring diagram.
Continuity should exist.
If OK, check harness of short-circuit.
OK
ENG Repair harness or connec-
tors
qA
YEC256A
NEF463
MEC947D
H
H
H
H
H
DTC P0216 INJ TIMING CONT/V, DTC P1246 F/INJ TIMG F/BTD27Ti
EC-406
http://vnx.su/