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Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 335 (Engine Controls - Self-Diagnostics - 3.0L) >> Diagnostic Tests >> DTC P0201-206: Injector Control Circuit >> Diagnostic Procedures

Diagnostic Procedures

WARNING: This page is about a different car, the 2003 Saturn Vue. 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, go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS .
    2. NOTE: If DTCs P0261, P0264, P0267, P0270, P0273, and P0276 are all set, inspect ignition 1 voltage supply circuit for a short to ground.
  2. Clear the DTCs with a scan tool. Crank or start engine. Does an injector DTC set? 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. Crank the engine or Start engine. Operate vehicle within the Conditions for Running the DTC. See CONDITIONS FOR RUNNING DTC  or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition? If yes, go to next step. If no, go to DIAGNOSTIC AIDS .
  4. Turn ignition off. Disconnect the fuel injector harness multi-way connector. Probe the appropriate fuel injector control circuit, ECM side, with a test light connected to battery voltage. Crank engine. Does the test light flash while cranking the engine? If yes, go to step  6. If no, go to next step.
  5. Test the control circuit of the fuel injector for an open between the multi-way connector and the ECM. Did you find and correct the condition? If yes, go to step  16. If no, go to step  12.
  6. Turn ignition on, with engine off. Probe the ignition 1 voltage supply circuit with a test light connected to a good ground. Does the test light illuminate? If yes, go to next step. If no, go to step  13.
  7. Inspect the accessible fuel injector jumper harness between the multi-way connector and the intake plenum for poor connections at the multi-way connector, damaged or pinched wiring, or broken wires inside the insulation. Repair as necessary. Did you find and correct the condition? If yes, go to step  16. If no, go to next step.
  8. Test for continuity between the ignition 1 voltage supply and the appropriate fuel injector control circuit, fuel injector side, at the multi-way connector with the DVOM. Does the DVOM indicate OL? If yes, go to next step. If no, go to step  11.
  9. Test the control circuit of the fuel injector for an open between the multi-way connector and the injector connector. Did you find and correct the condition? If yes, go to step  16. If no, go to next step.
  10. Test the ignition 1 voltage supply circuit of the affected fuel injector for an open between the fuel injector and the splice. Did you find and correct the condition? If yes, go to step  16. If no, go to next step.
  11. Test for an intermittent and for a poor connection at the fuel injector. Did you find and correct the condition? If yes, go to step  16. If no, go to step  14.
  12. Test for an intermittent and for a poor connection at the ECM. Did you find and correct the condition? If yes, go to step  16. If no, go to step  15.
  13. Repair the ignition 1 voltage supply circuit of the fuel injector for an open. After repairs, go to step  16.
  14. Replace fuel injector. After replacing fuel injector, go to step  16.
  15. Replace ECM. Perform ECM relearn procedures. See ENGINE CONTROL MODULE  under PROGRAMMING. After replacing ECM, go to next step.
  16. Clear the DTCs with a scan tool. Turn ignition off for 30 seconds. Start engine. Operate vehicle within the Conditions for Running the DTC. See CONDITIONS FOR RUNNING 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? If yes, go to step  2. If no, go to next step.
  17. Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? If yes, diagnose affected DTC(s). See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are displayed, system is okay.
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