IGNITION AND INJECTION
17
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DF002
PRESENT
OR
MEMORIZED
VALVE POTENTIOMETER CIRCUIT
1. DEF : Open circuit or short-circuit
AFTER
REPARATION
Perform the operations from “recommendations” for reparation confirmation.
Fix any other possible failures.
Erase the failures memorized by the injection computer.
Perform a conformity checking by means of the CLIP tester.
RECOMMENDATIONS
If failure “DF345 : Supply 5 volts potentiometers or transducers” is present
or memorized, this must be treated with priority.
Conditions for diagnostic application for memorized failure:
- Set the contact on and maintain it like this for 10 seconds in the released
pedal position.
- Easy alter the potentiometer valve position, from released pedal to maximum
acceleration.
- Maintain the pedal in the maximum pressed position for 10 seconds.
(The failure must pass to the present state, but it may become again memorized
immediately after finishing performing the previous operations).
* If the failure is memorized with OBD indicator on, check in the context part,
if state “ET284 : Valve potentiometer circuit” corresponding to the OBD
indicator lighting request is affirmative. In this case, proceed as per bellow
mentioned method.
Check the connection and the state of the valve potentiometer connector.
Replace its connector if necessary.
Perform measurement of the valve potentiometer resistance (resistance is zero or infinite in case of
sure failure).
Check that potentiometer resistance is progressively increasing, by acting upon the valve from
released acceleration pedal position to the maximal acceleration pedal.
(Use chapter “Help” in order to compare the measured resistance values compared with
recommended ones).
Check if the valve is well acting the potentiometer.
Make it working or replace the potentiometer if necessary.
Connect the 90 ways terminal box instead of the injection computer then check the insulation,
continuity and absence of the parasite resistance on lines:
Pin 75 injection computer
> pin A valve potentiometer
Pin 74 injection computer
> pin B valve potentiometer
Pin 43 injection computer
> pin C valve potentiometer.
Fix if necessary
If the problem is persisting after these checking, use the fixing method for failure DF345.
Diagnostic – Failures interpretation