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Home >> Jaguar >> 2000 >> XJR >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Trouble Code Identification >> DTC P1243: Sensor Ground Malfunction >> Diagnostic Test Procedure
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Diagnostic Test Procedure

  1. Disconnect the TPS connector. Measure resistance between TPS harness connector terminal No. 1 and ground. Is resistance greater than 5 ohms? If yes, go to next step. If resistance is less than 5 ohms, go to step  3.
  2. Disconnect ECM connectors EM82 and EM83. Measure resistance between TPS harness connector terminal No. 1 and the following:
    • ECM harness connector EM82 terminal No. 7.
    • ECM harness connector EM83 terminal No. 13.

    Are either resistance greater than 5 ohms? If yes, repair high resistance in appropriate circuit. If no, go to next step.

  3. Disconnect the PPS connector. Reconnect ECM connectors EM82 and EM83. Measure resistance between PPS harness connector terminal No. 3 and ground. Is resistance greater than 5 ohms? If yes, go to next step. If resistance is less than 5 ohms, go to step  5.
  4. Disconnect ECM connectors EM82 and EM83. Measure resistance between PPS harness connector terminal No. 3 and the following:
    • ECM harness connector EM82 terminal No. 7.
    • ECM harness connector EM83 terminal No. 13.

    Are either resistance greater than 5 ohms? If yes, repair high resistance in appropriate circuit. If no, go to next step.

  5. Disconnect FTP sensor connector. Reconnect ECM connectors EM82 and EM83. Measure resistance between FTP sensor harness connector terminal No. 1 and ground. Is resistance greater than 5 ohms? If yes, go to next step. If resistance is less than 5 ohms, go to step  7.
  6. Disconnect ECM connectors EM82 and EM83. Measure resistance between FTP sensor harness connector terminal No. 1 and the following:
    • ECM harness connector EM82 terminal No. 7.
    • ECM harness connector EM83 terminal No. 13.

    Are either resistance greater than 5 ohms? If yes, repair high resistance in appropriate circuit. If no, go to next step.

  7. Reconnect ECM connectors EM82 and EM83. Disconnect the ECT sensor connector. Measure resistance between ECT sensor harness connector terminal No. 1 and ground. Is resistance greater than 5 ohms? If yes, go to next step. If resistance is less than 5 ohms, go to step  9.
  8. Disconnect ECM connectors EM82 and EM83. Measure resistance between ECT sensor harness connector terminal No. 1 and the following:
    • ECM harness connector EM82 terminal No. 7.
    • ECM harness connector EM83 terminal No. 13.

    Are either resistance greater than 5 ohms? If yes, repair high resistance in appropriate circuit. If no, go to next step.

    9. NOTE: Intake Air Temperature (IAT) sensor is integral to Mass Airflow (MAF) sensor.
  9. Reconnect ECM connectors EM82 and EM83. Disconnect the MAF sensor connector. Measure resistance between MAF sensor harness connector terminal No. 5 and ground. Is resistance greater than 5 ohms? If yes, go to next step. If no, check for DTCs associated with the TPS, PPS, FTP sensor, ECT sensor and IAT sensor. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . Install a new sensor as indicated by the DTC.
  10. Disconnect ECM connectors EM82 and EM83. Measure resistance between MAF sensor harness connector terminal No. 5 and the following:
    • ECM harness connector EM82 terminal No. 7.
    • ECM harness connector EM83 terminal No. 13.

    Are either resistance greater than 5 ohms? If yes, repair high resistance in appropriate circuit. If no, go to next step.

    11. NOTE: Intake Air Temperature 2 (IAT2) sensor is on supercharged vehicles only.
  11. Reconnect ECM connectors EM82 and EM83. Disconnect IAT2 sensor connector. Measure resistance between IAT2 sensor harness connector terminal No. 1 and ground. Is resistance greater than 5 ohms? If yes, go to next step. If no, go to step  13.
  12. Disconnect ECM connectors EM82 and EM83. Measure resistance between IAT2 sensor harness connector terminal No. 1 and the following:
    • ECM harness connector EM82 terminal No. 7.
    • ECM harness connector EM83 terminal No. 13.

    Are either resistance greater than 5 ohms? If yes, repair high resistance in appropriate circuit. If no, go to next step.

  13. Reconnect ECM connectors EM82 and EM83. Disconnect the Engine Oil Temperature (EOT) sensor connector. Measure resistance between EOT sensor harness connector terminal No. 2 and ground. Is resistance greater than 5 ohms? If yes, go to next step. If no, check for DTCs associated with the TPS, PPS, FTP sensor, ECT sensor, IAT sensor, IAT2 sensor, or EOT sensor. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . Install a new sensor as indicated by the DTC.
  14. Disconnect ECM connectors EM82 and EM83. Measure resistance between EOT sensor harness connector terminal No. 2 and the following:
    • ECM harness connector EM82 terminal No. 7.
    • ECM harness connector EM83 terminal No. 13.

    Are either resistance greater than 5 ohms? If yes, repair high resistance in appropriate circuit. If no, check for DTCs associated with TPS, PPS, FTP sensor, ECT sensor, IAT sensor, IAT2 sensor, or EOT sensor. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . Install a new sensor as indicated by the DTC.

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