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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> External Pages >> Different car >> Section 12 (Engine Controls - Self-Diagnostics) >> Self-Diagnostic System >> Multiple Powertrain Control Module Information Sensor Diagnostic Trouble Codes Set >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Isuzu Trooper. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform ON-BOARD DIAGNOSTIC II SYSTEM CHECK . After performing OBD-II system check, go to next step.
  2. Turn ignition off. Disconnect PCM 80-pin harness connectors E-21 (Blue) and E-22 (Red). PCM is located at right rear of engine compartment. Turn ignition on. Check for poor connections, opens or shorts in either 5-volt reference circuits for affected sensors. See WIRING DIAGRAMS article. If problem is found, go to next step. If no problem is found, go to step  4.
  3. Repair faulty circuit as necessary. After repair is complete, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM.
  4. Check for poor connections or open in ground circuits of affected sensors. See WIRING DIAGRAMS article. If problem is found, go to next step. If no problem is found, go to step  6.
  5. Repair faulty circuit as necessary. After repair is complete, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM.
  6. Using scan tool, retrieve any stored DTCs. If DTC P1635 or P1639 is stored, perform appropriate diagnostic test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are stored, go to next step.
  7. Using DVOM, measure resistance of 5-volt supply circuit between following components:
    • EGR Pintle Position Sensor (GRIPS) and Fuel Vapor Pressure (FVP) sensor.
    • MAP sensor and FVP sensor.
    • FVP sensor and PCM harness connector.

    If no continuity exists, go to next step. If continuity exists, go to step  9.

  8. Locate and repair open in 5-volt reference circuit of MAP, EGR and FVP sensors. See WIRING DIAGRAMS article. After repair is complete, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM.
  9. Disconnect MAP, FVP and EGR sensor harness connectors. Measure resistance between each component's harness connector ground wire terminal and chassis ground. If resistance is about zero ohms on all circuits, go to step  11. If resistance is not as specified, go to next step.
  10. Locate and repair fault in MAP, EGR or FVP ground circuit. See WIRING DIAGRAMS article. After repair, retest system to verify repair.
  11. Using DVOM, measure resistance of 5-volt supply circuit between Crankshaft Position (CKP) and Camshaft Position (CMP) sensors. If resistance of each circuit is about zero ohms, go to step  13. If resistance is not as specified, go to next step.
  12. Locate and repair open in 5-volt reference or ground circuits for CKP and CMP sensors. See WIRING DIAGRAMS article. After repair, retest system to verify repair.
  13. Use scan tool to check for any stored EGR, FVP, MAP, CKP, CMP, TPS or APS related DTCs. If any listed DTCs are stored, perform appropriate diagnostic test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are stored, go to next step.
  14. Replace and reprogram PCM. See POWERTRAIN CONTROL MODULE REPLACEMENT  under POWERTRAIN CONTROL MODULE. Repeat OBD-II system check. See ON-BOARD DIAGNOSTIC II SYSTEM CHECK .
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