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Home >> Chevrolet >> 2003 >> Venture Base, Van Cargo Extended >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1106: Map System Performance >> Diagnostic Procedure
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Diagnostic Procedure

  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. Start engine. Using scan tool, Monitor the Diagnostic Trouble Code (DTC) information. Does the scan tool display DTC P0108 or P1635 set? If yes, see DTC P0108: MAP SENSOR CIRCUIT - HIGH VOLTAGE  or DTC P1635: 5-VOLT REFERENCE "A" CIRCUIT  . If no, go to next step.
  3. With scan tool, observe the MAP sensor voltage, while moving the following components:
    • MAP sensor connector.
    • Wiring harness related to the MAP sensor.
    • PCM connector.

    Is the MAP sensor voltage affected during any part of the test? If yes, go to next step. If no, go to step  8.

  4. Test the low reference circuit between the PCM and MAP sensor for an intermittent open or a high resistance. Did you find and correct the condition? If yes, go to step  8. If no, go to next step.
    5. NOTE: Disconnecting the PCM may eliminate the short during testing.
  5. Test the MAP sensor signal circuit between the PCM and MAP sensor for an intermittent short to voltage. Did you find and correct the condition? If yes, go to step  8. If no, go to next step.
  6. Test for an intermittent and for a poor connection at the MAP sensor. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 3.4L MONTANA, SILHOUETTE & VENTURE article. If yes, go to step  8. If no, go to next step.
  7. Inspect for intermittent or poor connections at the PCM. Did you find and correct the condition? If yes, go to next step. If no, see INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 3.4L MONTANA, SILHOUETTE & VENTURE article.
  8. Clear DTCs with scan tool. Turn ignition off for 30 seconds. Start engine. Operate vehicle within the Conditions for Running DTC. See CONDITIONS FOR RUNNING DTC . Does the DTC run and pass? If yes, go to next step. If no, go to step  2.
  9. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
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