Pinpoint Test G: Output Shaft Speed (OSS) Sensor

2005 Ford Taurus SEL, 4D SedanSECTION Pinpoint Test G: Output Shaft Speed (OSS) Sensor
NOTE: Refer to the Output Shaft Speed Sensor Harness Connector Illustration preceding these pinpoint tests.
  1. G1 ELECTRONIC DIAGNOSTICS 
    • Check that the output shaft speed (OSS) sensor connectors are fully seated, pins are engaged in connector and in good condition before proceeding.
    • Are the connectors OK? 
    • Yes  : GO to  G2.
    • No  : REPAIR as necessary. CLEAR the DTCs. REPEAT the OBD Tests.
  2. G2 CHECK THE CONTINUITY OF THE OSS HARNESS CIRCUITS 
    • Key in OFF position.
    • CAUTION: Do not pry on the connector. This will damage the connector and could result in a transaxle concern. Press the button and pull up on the connector.
    • Disconnect the OSS.
    • Disconnect: PCM.
    • Install the EEC-V Control System Breakout Box and leave the PCM disconnected.
    • Measure the resistance between the PCM signal test pin 84 at the EEC-V Control System Breakout Box and the +OSS signal circuit at the OSS harness connector.
      Fig 1: Measuring Resistance Between PCM Signal Test Pin 84 And +OSS Signal Circuit
      G03956712Courtesy of FORD MOTOR CO.
    • Measure the resistance between the PCM signal test pin 91 at the EEC-V Control System Breakout Box and the -OSS signal circuit at the OSS harness connector.
      Fig 2: Measuring Resistance Between PCM Signal Test Pin 91 And -OSS Signal Circuit
      G03956713Courtesy of FORD MOTOR CO.
    • Are all resistances less than 5 ohms? 
    • Yes  : GO to  G3.
    • No  : REPAIR the circuit(s) as necessary. CLEAR the DTCs. REPEAT the OBD Tests.
  3. G3 CHECK THE OSS CIRCUITS FOR A SHORT TO POWER AND GROUND 
    • Install the EEC-V Control System Breakout Box.
    • Measure the resistance between the PCM test pin 84 and test pin 71 at the EEC-V Control System Breakout Box.
      Fig 3: Measuring Resistance Between PCM Test Pin 84 And Test Pin 71
      G03956714Courtesy of FORD MOTOR CO.
    • Measure the resistance between the PCM test pin 84, and test pins 24, 25, 51, 76, 77, 91, and 103 at the EEC-V 104-Pin Breakout Box and chassis ground.
      Fig 4: Measuring Resistance Between PCM Test Pin 84 And Test Pins 24, 25, 51, 76, 77, 91, And 103
      G03956715Courtesy of FORD MOTOR CO.
    • Is each resistance greater than 10,000 ohms? 
    • Yes  : GO to  G4.
    • No  : REPAIR the circuit(s) as necessary. CLEAR the DTCs. REPEAT the OBD Tests.
  4. G4 TRANSMISSION FUNCTIONAL TEST 
    • Connect: PCM.
    • Using the OSS adapter connector connect the transmission tester to the OSS sensor.
    • With the voltmeter set to AC, measure the voltage with the positive lead to +TSS/OSS and the negative lead to -TSS/OSS.
      Fig 5: Measuring Voltage With Positive Lead To +TSS/OSS And Negative Lead To -TSS/OSS
      G03956716Courtesy of FORD MOTOR CO.
    • Carry out the OSS Voltage Test under Dynamic Testing Engine ON, refer to the transmission tester manual. Monitor the voltmeter.
    • Does the voltage increase with an increase in vehicle speed? 
  5. G5 CHECK THE RESISTANCE OF THE OSS SENSOR 
    • NOTE: Refer to the transmission tester for pin locations.
    • Measure the resistance with the negative lead to -TSS/OSS jack and the positive lead to +TSS/OSS jack on the tester.
      Fig 6: Measuring Resistance With Negative Lead To -TSS/OSS Jack And Positive Lead To +TSS/OSS Jack
      G03956717Courtesy of FORD MOTOR CO.
    • Is the resistance between 235 and 735 ohms? 
    • Yes  : GO to  G6.
    • No  : INSTALL a new OSS sensor. REPEAT the OSS Function Test.
  6. G6 CHECK THE SENSOR FOR A SHORT TO GROUND 
      NOTE: Connection should show infinite resistance (no continuity).
RENDER: 1.0x

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