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Home >> Mercury >> 2009 >> Sable Premier, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1255 (Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid)) >> DTC Diagnosis >> DTC P0721: - Output Shaft Speed (OSS) Sensor Circuit Range/Performance

DTC P0721: - Output Shaft Speed (OSS) Sensor Circuit Range/Performance

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DTC P0721: - OUTPUT SHAFT SPEED (OSS) SENSOR CIRCUIT RANGE/PERFORMANCE

Description:  The OSS sensor signal is very sensitive to noise. This noise distorts the input to the powertrain control module (PCM).
Possible Causes: 
  • Wiring misrouted
  • Aftermarket add-on
  • Wiring damaged
  • Wiring insulation wear
Diagnostic Aids:  Check the routing of the harness.
Check the wiring and the connector for damage.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Manual Transmission - - GO to Pinpoint Test DP .
Automatic Transmission Refer to the AUTOMATIC TRANSAXLE/TRANSMISSION - 5R55S Cooling Symptom Chart, Diagnostic Trouble Code (DTC) Index to continue diagnosis.