Some Ford Motor Company, 1996 and later vehicles equipped with the 4R70W transmission may exhibit a neutral condition from a stop, when the Shift Selector is in the “D” range. There may also be a Diagnostic Trouble Code P0755 stored, which is "Shift Solenoid 2 ElectricalCircuitFault". Therecanbethreedifferentcausesforthisconcern.
One cause for this condition may be that the PPL/ORG or VIO/ORG wire, which is model dependant,andcontrolsShiftSolenoid2, mayhaverubbedontherearoftheengine,causing the circuit to become grounded. When this occurs with the transmission in first gear, Shift Solenoid2closesandfluidpressureactstostroke the3-4ShiftValvetotheright,causingthe ForwardClutchoiltoexhaustthrough the3-4ShiftValve,creatingtheneutralcondition. Refer to Figure 86 for hydraulic schematic. Diagnostic Trouble Code (DTC) P0755 may also be stored in memory.
Another cause for this condition may be, the Solenoid Regulator Valve has become stuck down,inthebottomoftheValveBodybore,causingthepressureintheSolenoid Regulator Circuit to become higher than what the Shift Solenoid can exhaust. This will allow the ShiftSolenoid2pressuretobuildupandstroke the3-4ShiftValvetotherightexhausting the Forward Clutch oil, creating a neutral condition. Refer to Figure 87 for hydraulic schematic. No Diagnostic Trouble Codes will be stored.
Refer to Figure 88 and 89 for valve identification.
Cause 3 is almost identical to Cause 2 with the exception being that Shift Solenoid 2 is sticking closed, or has debris built up at the solenoid exhaust hole, which will allow Shift Solenoid 2 pressure to build up which causes the 3-4 Shift Valve to move to the right exhaustingtheForwardClutchoil,andonceagaincreatingtheneutralcondition. Referto Figure87forhydraulicschematic. NoDiagnosticTroubleCodeswillbestored.
Technical Service Information
CORRECTION: To follow proper diagnostic procedure for this problem, attach a pressure gauge to the Forward Clutch Pressure Port which is located on the right hand side of the transmission, as shown in Figure 90. Normally when the Forward Clutch is applied, the pressure will be equaltotheMainLinepressure,asshowninFigure91. Whentheabovecausestakeplace, the pressure seen at the Forward Clutch will suddenly drop to zero, and this is when the neutral condition will be felt.
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AUTOMATIC TRANSMISSION SERVICE GROUP
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Repair or replace the damaged Shift Solenoid 2 wire. Refer to Figure 92, for an index to locate the proper year and model vehicle that you are working on, and refer to schematic for thatvehicle. WireschematicshavebeenprovidedinFigures93,94,95and96.
Locate the Solenoid Regulator Valve in the Valve Body, as shown in Figure 88. To repair a sticking Solenoid Regulator Valve, it may become necessary to replace the valve assembly. TherearereplacementSolenoidRegulatorValveKitsavailablefromaftermarketsuppliers.
ReplacethecompleteShiftSolenoidAssembly.
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