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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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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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Diagnostic – Failures interpretation
DF 261 FUEL PUMP RELAY CIRCUIT
P RESENT 1. DEF Supply failure + after relay
OR 2. DEF Open circuit or short-circuit
ME MO RIZED
If failure “DF345 : Supply 5 volts potentiometers and sensor s” is
present or memori zed, it must be treated as most important .
Conditions for diagnostic appl ication at memorized failure:
Se t the contact on, then enter in dia logue with the computer
Or activation of the actua tor control “ AC 010 : Fuel pump relay”.
RECOMMEND ATIONS REMARK : This failure is most important. So it must be treated before
t he next ones.
* If the failure is memorized with OBD indicator on, check in the context
part, if state “ET241 : Fuel pump control cir cuit” corresponding to the
OBD indicator lighting request is affir mative. In this case , proceed as
per bellow mentioned method
1. DEF RECOM MENDAT IONS It is a failure on the power circuit of the fuel
pump relay.
C heck the electric continuity f the idleness contact.
Me nd if necessary.
C heck the connection and con dition of the fuel pump relay connector .
R eplace the connector if necessary.
C heck the presence of the +12 volts supply at pole 3 of the fuel pump relay
Me nd if necessary.
C heck with the contact set on a nd acting the actuator c ontrol “AC010 : Fuel pump relay”, the
prese nce of +12 V supply at pole 5 of the fuel pump relay.
R eplace the relay if necessa ry
C heck the insu lation and cont inuity of the connections between:
Pole 5 fuel pump relay > pi n C ignition coil
Pole 5 fuel pump relay > fuel pump
Me nd if necessary.
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.
AF TER Fix any other possible failures
REPARATION Erase the failures memoriz ed by the injection computer.
Perform a conformity checking by means of the CLIP tester.
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