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Pinpoint Test Z: DTC P1243; SENSOR GROUND CIRCUITS OPEN CIRCUIT

NOTE: The sensor ground circuit includes splices, EMS2, and PIS1. If one sensor has a ground where others do not, check the harness from splices to other sensors for continuity. Refer to the wiring diagrams.
NOTE: Early production vehicles have wire color codes that are different from that shown. Use connector pin numbers for wire identification.
  1. CHECK THE SENSOR GROUND AT THE THROTTLE SENSORS 

    Disconnect the throttle sensor electrical connector, PI06.

    Measure the resistance between PI06, pin 01 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  2.

    NO:  Go to step  3.

  2. CHECK THE THROTTLE SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI06, pin 01 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  3.

  3. CHECK THE SENSOR GROUND AT THE APP SENSOR 

    Disconnect the APP sensor electrical connector, EM06.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between EM06, pin 06 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  4.

    NO:  Go to step  5.

  4. CHECK THE APP SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between EM06, pin 06 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  5.

  5. CHECK THE SENSOR GROUND AT THE FUEL TANK PRESSURE SENSOR 

    Disconnect the FTP sensor electrical connector, FT02.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between FT02, pin 01 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  6.

    NO:  Go to step  7.

  6. CHECK THE FUEL TANK PRESSURE SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between FT02, pin 01 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  7.

  7. CHECK THE SENSOR GROUND AT THE ECT SENSOR 

    Reconnect the ECM electrical connector, EM80.

    Disconnect the ECT sensor electrical connector, PI04.

    Measure the resistance between PI04, pin 01 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  8.

    NO:  Go to step  9.

  8. CHECK THE ECT SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI04, pin 01 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  9.

  9. CHECK THE SENSOR GROUND AT THE IAT SENSOR (MAF) 

    Disconnect the IAT sensor (MAF) PI35.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between PI35, pin 05 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  10.

    NO:  Go to step  11.

  10. CHECK THE IAT SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI35, pin 05 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  11.

  11. CHECK THE SENSOR GROUND AT THE IAT 2 SENSOR 

    Disconnect the IAT 2 sensor electrical connector, PI03.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between PI03, pin 02 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  12.

    NO:  Go to step  13.

  12. CHECK THE IAT 2 SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI03, pin 02 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  13.

  13. CHECK THE SENSOR GROUND AT THE MAP SENSOR 

    Disconnect the MAP sensor electrical connector, PI25.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between PI25, pin 04 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  14.

    NO:  Go to step  15.

  14. CHECK THE MAP SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI25, pin 04 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  15.

  15. CHECK THE SENSOR GROUND AT THE EFT SENSOR 

    Disconnect the EFT sensor electrical connector, PI24.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between PI24, pin 02 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  16.

    NO:  Go to step  17.

  16. CHECK THE EFT SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI24, pin 02 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  17.

  17. CHECK THE SENSOR GROUND AT THE IP SENSOR 

    Disconnect the IP sensor electrical connector, PI43.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between PI43, pin 02 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  18.

    NO:  Go to step  19.

  18. CHECK THE IP SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI43, pin 02 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  19.

  19. CHECK THE SENSOR GROUND AT THE EOT SENSOR 

    Disconnect the EOT sensor electrical connector, PI38.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between PI38, pin 02 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  20.

    NO:  Check for DTCs relating to individual sensors. Carry out pinpoint tests for sensors indicated.

  20. CHECK THE IP SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI38, pin 02 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Go to step  21.

  21. CHECK THE SENSOR GROUND AT THE A/C PRESSURE SENSOR 

    Disconnect the A/C pressure sensor electrical connector, PI38.

    Reconnect the ECM electrical connector, EM80.

    Measure the resistance between LF20, pin 01 (BG) and GROUND.

    Is the resistance greater than 5 ohms? 

    YES:  Go to step  22.

    NO:  Check for DTCs relating to individual sensors. Carry out pinpoint tests for sensors indicated.

  22. CHECK THE A/C PRESSURE SENSOR GROUND CIRCUIT FOR HIGH RESISTANCE 

    Disconnect the ECM electrical connector, EM80.

    Measure the resistance between PI38, pin 02 (BG) and EM80, pin 19 (BG).

    Is the resistance greater than 5 ohms? 

    YES:  REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation.

    NO:  Check for DTCs relating to individual sensors. Carry out pinpoint tests for sensors indicated.

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