IGNITION AND INJECTION1717 - 26DF002PRESENTORMEMORIZEDVALVE POTENTIOMETERCIRCUIT1. DEF : Open circuit or short-circuitAFTERREPARATIONPerform 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.RECOMMENDATIONSIf failure “DF345: Supply 5 volts potentiometers or transducers” is presentor memorized, this must be treatedwith priority.Conditions for diagnostic application for memorized failure:- Set the contact on and maintain it like this for 10 seconds in the releasedpedal position.- Easy alter the potentiometer valve position, from released pedal to maximumacceleration.- Maintain the pedal in the maximum pressed position for 10 seconds.(The failure must pass to the present state, butit may become again memorizedimmediately 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 OBDindicator lighting request is affirmative. In this case, proceed as per bellowmentioned 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 ofsure failure).Check that potentiometer resistance is progressively increasing, by acting upon the valve fromreleased acceleration pedal position to the maximal acceleration pedal.(Use chapter “Help” in order to compare the measured resistance values compared withrecommended 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 potentiometerPin 74 injection computer > pin Bvalve potentiometerPin 43 injection computer > pin C valve potentiometer.Fix if necessaryIf the problem is persisting after these checking, use the fixing method for failure DF345.Diagnostic – Failures interpretationvnx.su
