LEMON Manuals: Even more car manuals for everyone
Home >> Hummer >> 2008 >> H2 4D Utility Wagon >> Repair and Diagnosis >> External Pages >> Different car >> Section 514 (Engine Controls/Fuel - Hybrid (LZ1) - DTC P0351 To DTC P3449 And Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> DTC P0446 >> Circuit/System Verification

Circuit/System Verification

WARNING: This page is about a different car, the 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, open the hood to disable the Auto-Stop function. Refer to Hybrid Modes of Operation Description .
  2. Ignition ON, verify the scan tool hood position parameter displays Open.
  3. Ignition ON and fuel cap removed, verify that the FTP sensor parameter is between 1.3-1.7 V.
    • If not within the specified range, go to the FTP sensor section in Circuit/System Testing.
  4. Install the fuel cap.
  5. With the engine running, the EVAP vent solenoid valve open, use a scan tool to command the EVAP purge solenoid valve to 100 %. The fuel tank vacuum should not increase to more than -15 mm Hg (-8 in H2O).
    • If greater than the specified range, go to the restriction section in Circuit/System Testing.
  6. Using the scan tool, decrease the canister purge duty cycle from 100 % to 0 %. The vacuum should decrease to near zero.
    • If the fuel tank vacuum does not return to zero or appears to decrease too slowly go to the restriction section in Circuit/System Testing.
  7. 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 data.