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Perform the operations from ” recommendations” for reparation confirma tion.
Fi x any other possible failures.
Erase the failures memoriz ed by the injection computer.
Pe rform a conformity checking by means of the CLIP tester.
AF
TER
REPARATION
CYLINDER 4 INJECTOR CIRCUIT
1. DEF : Open circuit or short-circuit
CO : open circuit
CC.O : s hot circuit at mass
CC.1 : s hort circuit at + 12 V.
DF 055
P RESENT
OR
MEMO RIZED
Conditions for diagnostic appl ication to memorized failure:
Start the engine and especially stop it immediately the failure i s becoming
present, so that catalyst-dama ging risk is avoide d.
In case of failures addition, treat as most important, failure “ DF009
actua tors relay control cir cuit”
* If the failure is memorized with OBD indicator on, check in the context
part, if state “ET281 : Cylinder 4 injector circuit” corresponding to the
OBD indicator lighting request is affirmative. In this case, proceed as per
bellow mentioned method
C heck the connection and condition of the injector 4 connector.
R eplace the connector if necessary.
C heck the injector 4 resistance. Refer to chapter “Help” in order to compare the resistance values.
R eplace the injector if necessary.
When setting the contact on, check the presence of supplying +12 V on pin 1 of the injector 4.
Fix, if necessary the electric routing up to actua tors relay.
C onnect the 90 ways terminal box instead of the injection computer the n check the insulation and
continuity on line :
pi n 89 injection computer > pin 2 injector 4
Fi x if necessary.
If after these checking the problem is persisting, treat the other failures then perform the conformity
checking
Diagnostic – Failures interpretation
RE COMMENDATIONS
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DF 057
P RESENT
OR
ME MO RIZED
If failure “ DF345” : Supply 5 volts potentiometers or sensor s” is
prese nt or memoriz ed, this must be treate d as most important.
Conditions for diagnostic appl ication to memorized failure:
Se t the contact on.
St art the engine, ensur e tha t state “ET030: Upstream oxygen se nsor
he a ting” is ACTI VE a nd w a it tha t sta te “ ET037 : Enr ic hing
adjustment ” is ACTIVE, t hen wait for 5 minutes.
* If the failure is memorized with OBD indicator on, check in the
context part, if state “ET285 : Upstream oxygen sensor circuit” corre-
s ponding to the OBD indicator lighting request is affirma tive. In this
case , proceed as per bellow mentioned method.
RE COMMENDATIONS
UPSTREAM OXYGEN SENSOR CIRCUIT
1.DEF : Open circuit or short-circuit
C heck the connection and condition of the oxygen sensor connector
Check if there is no water penetration in connector (a possible cause for engine unstable running)
R eplace the connector if necessary.
C heck for lack of tightening between the exhaust collector and catalyst
If the vehicle is running more in the city, perform a cleaning of the oxygen se nsor.
C onnect the 90 ways terminal box instead of the injection computer the n check the insulation,
continuity and absence of the parasite resistance on lines: Pin 45 injection computer > pi n C oxygen sensor
Pin 80 injection computer > pi n D oxygen sensor
Fi x if necessary.
If the proble m is persisting, replace the oxygen sensor.
If the problem is persisting after these checking, treat the other failures then perform the conformity
checking.
Perform the operations from ” recommendations” for reparation confirma tion.
Fi x any other possible failures
Erase the failures memoriz ed by the injection computer.
Pe rform a conformity checking by means of the CLIP tester.
AF
TER
REPARATION
Diagnostic – Failures interpretation
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IGNITION AND INJECTION
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If failure “DF345” : Supply 5 volts potentiometers or sensors” is present or
memorize d, this must be treated as most important.
Conditions for diagnostic appl ication to memorized failure:
- During road test, smooth driving, after an engine fan starting and state
“ET027: Enriching double loop” to be active.
- During road test, smooth driving, after an engine fan starting, immediately
followed by a deceleration (rising gradie nt) with sta te “ET003: Released
pedal valve pos ition” active, gearbox ratio engaged and clutched.
* If the failure is memoriz ed with OBD indicator on, check in the context
part, if state “ET287 : Downstream oxygen sensor circuit” corresponding
to the OBD indicator lighting request is affirmative. In this case , proceed
as per bellow mentioned method
C heck the connection and condition of the oxygen sensor connector
R eplace the connector if necessary.
C heck for lack of tightening on the routing between the two oxygen sensors.
If the vehicle is running more in the city, perform a cleaning of the oxygen sensor.
C onnect the 90 ways terminal box instead of the injection computer then c heck the insulation,
continuity and absence of the parasite resistance on lines: Pin 44 injection computer > pin C oxygen sensor
Pin 76 injection computer > pin D oxygen sensor
Fix if necessary.
If the proble m is persisting, replace the oxygen sensor.
If the problem is persisting after these checking, treat the other failures then perform the conformity
checking.
Perform the operations from ” recommendations” for reparation confirma tion.
Fix a ny other possible failures.
Erase the failures memoriz ed by the injection computer.
Perform a conformity checking by means of the CLIP tester.
AF
TER
REPARATION
Diagnostic – Failures interpretation
DF 058
P RESENT
OR
ME MO RIZEDDOWNSTREAM OXYGEN SENSOR CIRCUIT
1.DEF : Open circuit or short-circuit
RE CO MME NDAT I O N S
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IGNITION AND INJECTION
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Conditions for diagnostic appl ication to memorized failure:
Set t he contact on.
* If the failure is memorized with OBD indicator on, check in the context
part, if state “ET255 : Idling adjustment circuit” corresponding to the
OBD indicator lighting request is affirmative. In this case , proceed as
per bellow mentioned method.
RE CO MM ENDATIONS
After repairing the step-by-step engine for idling adjustment, it may possible
that engine is not starting; in this situation, the “learning” stage of the adaptive
values by the injection computer must be again pe rformed (se e c hapter “
Enriching adaptive correction”).
Fi x any other possible failures then perform a conformity checking by means of
t he CLIP tester.
AF
TER
REPARATION
DF 060
P RESENT
OR
ME MO RIZEDIDLING ADJUSTMENT CIRCUIT
1.DEF : Open circuit or short-circuit
CO : Open circuit
CC. O : Short-circuit at mass
CC.1 : S hort-circuit at +12 volts
Check the connection and condition of the step-by-step engine connector for idling adjustment
R eplace the connector if necessary.
C heck the resistance of the step-by-step engine for idling adjustment. Refer to chapter “Help” in
order to compare the measur ed resistance values with the recommended ones.
R eplace the step-by-step e ngine valves if necessa ry.
C heck the insu lation, continuity and absence of the p arasite resistance on lines:
Pin 12 injection computer > pin B step-by-step engine for idling adjustment
Pin 41 injection computer > pin A step-by-step engine for idling adjustment
Pin 42 injection computer > pin C step-by-step engine for idling adjustment
Pin 72 injection computer > pin D step-by-step engine for idling adjustment
Fix if necessary.
If the problem is persisting after these checking, treat the other failures then perform the conformity
checking.
Diagnostic – Failures interpretation
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DF 061
P RESENT
OR
ME MO RIZEDCYLINDERS 1-4 IGNITION COIL CIRCUIT
1.DEF : Open circuit or short-circuit
CO : Open circuit
CC. O : Short-circuit at mass
CC.1 : S hort-circuit at +12 volts
Conditions for diagnostic appl ication to memorized failure:
Start t he e ngine a nd stop it immediately as the failure is oc curring as being
prese nt (risk for catalyst) or rota te de engine with the starter, without starting it,
for 10 seconds.
In case of failures addition, treat as most important, failure “ DF345 : Supply 5
volts potenti ometers or sensors “ and failure “DF261: Fuel pump relay circui t”,
if it is /they are present
* If the failure is memorized with OBD indicator on, check in the context part, if
st ate “ET282 : Ignition coil 1-4 circuit” corresponding to the OBD indicator
lighting request is affirmative. In this case , proceed as per bellow mentioned
met hod
C heck the connection and condition of the coil connector .
R eplace the connector if necessary.
C heck the resistance of the coil resistance of c ylinders 1-4. Refer to chapte r
“Help” in order to compare the measured resistance values with the recommended
one .
R eplace the coil if necessary.
Check the +12 Volts supply existence after fue l pump relay, at pin C of the coi l.
If it is necessary, apply the methodology for failure diagnostic “DF261”
C onnect the 90 ways terminal box instead of the injection computer the n check
t he insulation and continuity on line:
pin 32 injection computer > pin A ignition coil.
Fi x if necessary.
If the problem is persisting after the se checking, treat the other failures then
perform the conformity checking.
RECOMMENDATIONS
Pe rform the operations from ” recommendations” for reparation confirma tion.
Fi x any other possible failures
Erase the failures memoriz ed by the injection computer.
Pe rform a conformity checking by means of the CLIP tester.
AF
TER
REPARATION
Diagnostic – Failures interpretation
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Diagnostic – Failures interpretation
DF 062
P RESENT
OR
ME MO RIZED CYLINDERS 2-3 IGNITION COIL CIRCUIT
1.DEF : Open circuit or short-circuit
CO : Open circuit
CC. O : Short-circuit at mass
CC.1 : S hort-circuit at +12 volts
Conditions for diagnostic appl ication to memorized failure:
Start t he engine a nd stop it immediately as the failure is occurring as be ing
prese nt (risk for catalyst) or rota te de engine with the starter, without starting
it, for 10 seconds.
In case of failures addition, treat as most important, failure “ DF345 : Supply 5
volts potentiometers or sensors “ and f ailure “DF261: Fuel pump relay
circuit ”, if it is /they are present.
* If the failure is memorized with OBD indicator on, check in the context part, if
st ate “ET283 : Ignition coil 2-3 circuit” corresponding to the OBD indicator
lighting request is affirmative. In this case , proceed as per bellow me ntioned
met hod.
C heck the connection and condition of the coil connector .
R eplace the connector if necessary.
C heck the resistance of the coil resistance of c ylinders 2 and 3. Refer to
chapte r “ Help” in order to compare the measured resistance values with the
recommended one.
R eplace the coil if necessary.
Check the +12 Volts supply existence after fuel pump relay, at pin C of the
coil.
If it is necessary, apply the methodology for failure diagnostic “DF261”.
C onnect the 90 ways terminal box instead of the injection computer then check
t he insulation and continuity on line:
pin 1 injection computer > pin B ignition coil.
Fix if necessary..
If the problem is persisting after these checking, treat the other failures then
perform the conformity checking.
RECOMMENDATIONS
Pe rform the operations from ” recommendations” for reparation confirma tion.
Fi x any other possible failures.
Erase the failures memoriz ed by the injection computer.
Pe rform a conformity checking by means of the CLIP tester.
AF
TER
REPARATION
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DF 064
P RESENT
OR
ME MO RIZED
REC OMMENDATIONS
Conditions for diagnostic appl ication to memorized failure:
P erform a drive te st and notice the vehicle speed.
C ontinue to perform the drive test uphill at constant speed.
C ontinue to perform the drive test uphill, the acceleration pedal not being
pushe d.
* If the failure is memoriz ed with OBD indicator on, check in the context
part, if state “ET223 : Vehicle speed transducer circuit” corresponding to
t he OBD indicator lighting request is affirma tive. In this case , proceed as
per bellow mentioned method
C heck the connection and condition of the speed transduc er connector .
R eplace the connector if necessary.
C onnect the 90 w ays terminal box instead of the injection computer then check the insulation,
continuity and the absence of the parasite resistance on line 53 of the injection computer on line.
If the problem is persisting, replace the spe ed tr ansducer.
Pe rform the operations from ” recommendations” for reparation confirma tion.
Fi x any other possible failures.
Erase the failures memoriz ed by the injection computer.
Pe rform a conformity checking by means of the CLIP tester.
AF
TER
REPARATION
Diagnostic – Failures interpretation
VEHICLE SPEED INFORMATION
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DF102
P RESENT
OR
ME MO RIZED
C heck for leakage on exhaust line.
If the vehicle is mostly driven in town, perform an oxygen sensor cleaning.
C heck the connection and condition of the oxygen sensor connector .
R eplace the connector if necessary.
C onnect the 90 ways terminal box instead of the injection computer then check the insulation,
continuity and the absence of the parasite resistance on lines: Pin 45 injection computer > pin C upstream oxygen sensor
Pin 80 injection computer > pin D upstream sensor
Pin 63 injection computer > pin B upstream sensor
Fi x it if necessary.
If the proble m is persisting, repla ce the oxygen sensor.
If the problem is persisting after these checking, treat the other failures then perform the conformity
checking.
Note any other functional failures.
Fix any other possible failures.
AF
TER
REPARATION
RE COMMENDATIONS
OXYGEN SENSOR FUNCTIONAL FAILURE
It shows an incoherent information received b means of the upstream
oxygen sensor.
Apply this diagnostic if the failure is prese nt or memorized.
Diagnostic – Failures interpretation
vnx.su