LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 103 (Engine Controls Self-Diagnostics - 2.2L) >> Diagnostic Tests >> DTC P0201-P0204: Injector Control Circuit >> Diagnostic Procedures

Diagnostic Procedures

WARNING: This page is about a different car, the 2002 Pontiac Sunfire, 2002 Pontiac Grand Am, 2002 Oldsmobile Alero, and 2002 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check - engine controls, go to next step.
  2. Clear the DTCs with a scan tool. Idle the engine at the normal operating temperature. Monitor the misfire current counters with a scan tool. Are any of the counters incrementing? If yes, go to step  4. If no, go to next step.
  3. Observe the Freeze Frame/Failure Records data for this DTC. Turn ignition off for 30 seconds. Start engine. Operate the vehicle within the Conditions for Running the DTC or as close to the Freeze Frame/Failure Records data that you observed. See CONDITIONS FOR RUNNING DTC . Does the DTC fail this ignition? If yes, go to next step. If no, go to DIAGNOSTIC AIDS .
  4. Turn ignition off. Remove air cleaner outlet resonator. Disconnect appropriate harness connector of the fuel injector. Turn ignition on, with engine off. Probe the ignition 1 voltage supply circuit of the fuel injector harness connector with test light connected to a good ground. Does test light illuminate? If yes, go to next step. If no, go to step  11.
  5. Connect the J-34730-405 Fuel Injector Test light between the control circuit and the ignition 1 voltage supply circuit of the fuel injector harness connector. Start engine. Does the test light flash? If yes, go to step  9. If no, go to next step.
  6. Does the test light remain illuminated at all times? If yes, go to step  8. If no, go to next step.
  7. Test the control circuit of the fuel injector for a short to voltage and 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 injector for a short to ground. Did you find and correct the condition? If yes, go to step  14. If no, go to step  13.
  9. Inspect for poor connections at the harness connector of the fuel injector. Did you find and correct the condition? If yes, go to step  14. If no, go to step  12.
  10. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step  14. If no, go to step  13.
  11. Repair ignition 1 voltage supply circuit of the fuel injector for an open or a short to ground. After repairs, go to step  14.
  12. Replace fuel injector. When complete, go to step  14.
  13. Replace PCM. See POWERTRAIN CONTROL MODULE in appropriate REMOVAL, OVERHAUL & INSTALLATION article. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE REPROGRAMMING  under PROGRAMMING. After replacing PCM, go to next step.
  14. Use the scan tool in order to clear the DTCs. Turn ignition off for 30 seconds. Start engine. Operate the vehicle within the Conditions for Running the DTC. See CONDITIONS FOR RUNNING DTC . Does the DTC run and pass? If yes, go to next step. If no, go to step  2.
  15. With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
scientia non olet · About LEMON Manuals