2005 MY OBD System Operation Summary for Gasoline Engines

4:=%:.)%:> );;The Transmission Range Sensor (TRS) provides five digital inputs, one for Park and Neutral, one for Reverse, onefor Drive, one for Second and one for First. These inputs are monitored for opens and shorts (P0705).The Turbine Shaft Speed (TSS) sensor and Output Shaft Speed (OSS) sensors are analog inputs that arechecked for rationality. If the engine rpm is above the torque converter stall speed or one of the two speed sensorshas sufficient signal and engine load is high enough, it can be inferred that the vehicle must be moving. If there isinsufficient output from the TSS sensor, a malfunction is indicated (P0715). If there is insufficient output from theOSS sensor, a malfunction is indicated (P0720).;Shift SolenoidsThe Shift Solenoid (SSA, SSB, SSC, SSD, and SSE) output circuits are checked for opens and shorts by the PCMby monitoring the status of a feedback circuit from the output driver (P0750, P0755, P0760, P0765 and P0770respectively).The shift solenoids are functionally (mechanically) checked by means of a comprehensive malfunction pattern test.This monitor examines learned gear states and the TCC function to determine if a shift solenoid mechanical failurehas occurred(P0751, P0756, P0761, P0766 and P0771 respectively).Torque Converter ClutchNo single solenoid controls the TCC in the FN. Electrical checks for all shift solenoids are performed as indicatedabove. The TCC is checked functionally by evaluating torque converter slip under steady state conditions when thetorque converter is fully applied. If the slip exceeds the malfunction thresholds when the TCC is commanded on, aTCC malfunction is indicated (P0741). If slip is below an open converter threshold when the TCC is commandedoff, a TCC malfunction is indicated through the shift solenoid functional test (P0756).FORD MOTOR COMPANY REVISION DATE: APRIL 28, 2004 PAGE 118 OF 131