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Home >> Cadillac >> 2007 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 119 (Engine Controls Self-Diagnostics) >> Diagnostic Tests >> DTC P0230: Fuel Pump Control Relay Circuit >> Diagnostic Procedures
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Diagnostic Procedures

WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
  1. Did you perform the Diagnostic System Check-Engine Controls? If yes, go to next step. If no, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition ON, with engine OFF. Command fuel pump ON and OFF with a scan tool. Does the fuel pump relay turn ON and OFF with each command? If yes, go to next step. If no, go to step  4.
  3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see INTERMITTENT CONDITIONS  under SELF-DIAGNOSTIC SYSTEM.
  4. Turn ignition OFF. Remove fuel pump relay. Turn ignition ON, with engine OFF. Probe the control circuit of the fuel pump relay with a test light connected to a good ground. Command the fuel pump relay ON and OFF with a scan tool. Does the test light turn ON and OFF when commanded with a scan tool? If yes, go to next step. If no, go to step  6.
  5. Connect a test light between the control circuit of the fuel pump relay and the ground circuit of the fuel pump relay. Command the fuel pump relay ON and OFF with a scan tool. Does the test light turn ON and OFF when commanded with a scan tool? If yes, go to step  9. If no, go to step  11.
  6. Does the test light remain illuminated? If yes, go to step  8. If no, go to next step.
  7. Test the control circuit of the fuel pump relay for a short to ground or for an open. Did you find and correct the condition? If yes, go to step  14. If no, go to step  10.
  8. Test the control circuit of the fuel pump relay for a short to voltage. Did you find and correct the condition? If yes, go to step  14. If no, go to step  10.
  9. Test for an intermittent and/or poor connections at the fuel pump relay. Did you find and correct the condition? If yes, go to step  14. If no, go to step  12.
  10. Test for an intermittent and for a poor connection at the PCM. Did you find and correct the condition? If yes, go to step  14. If no, go to step  13.
  11. Test the ground circuit of the fuel pump relay for an open. Did you complete the repair? If yes, go to step  14.
  12. Replace fuel pump relay. Did you complete the replacement? If yes, go to step  14.
  13. Replace PCM. See POWERTRAIN CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL & INSTALLATION - CORVETTE article. Did you complete the replacement? If yes, go to next step.
  14. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition cycle? If yes, go to step  2. If no, go to next step.
  15. Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
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