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Home >> Cadillac >> 2009 >> Escalade Base, AWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 12 (Engine Control System & Fuel - Hybrid (Hp2) 6.0L (LFA) - DTC P0010 To DTC P0232) >> DTC P0068 or P0121 >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.
  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. Inspect for the following conditions:
    • Vacuum hoses for splits, kinks, and proper connections as shown on Vehicle Emission Control Information label
    • Inspect thoroughly for any type of leak or restriction
    • Air leaks at throttle body mounting area and intake manifold sealing surfaces
    • Throttle body for dirt, debris, and coking-Refer to Throttle Body Cleaning .
  4. Ignition ON, engine OFF, observe the MAP Sensor Voltage parameter with a scan tool. Voltage should be more than 0.8 volt and less than 4.85 volts.
    • If more than 4 volts or less than 0.8 volt, refer to DTC P0106 .
  5. Start and idle the engine. Observe the MAP Sensor kPa parameter with a scan tool. Increase the engine speed slowly and then back to idle. The MAP sensor kPa should change smoothly and gradually as engine speed is increased and returned to idle.
    • If the MAP sensor kPa does not change, refer to DTC P0106 .
  6. Take a snapshot of the engine data list while performing the actions listed below. The mass air flow (MAF) sensor g/s should change smoothly and gradually as the engine speed is increased and is returned to idle.
    • Idle the engine.
    • Increase the engine speed slowly to 3,000 RPM, then back to idle.
    • Exit from the snapshot and review the data.
    • Observe the Mass Air Flow (MAF) Sensor parameter frame by frame with a scan tool. The MAF sensor g/s should change smoothly and gradually as the engine speed is increased and is returned to idle.
    • If the MAF sensor g/s does not change smoothly and gradually as the engine speed is increased and is returned to idle, refer to DTC P0101 or P1101 .
  7. Inspect the throttle body for the following conditions:
    • Loose or damaged throttle blade
    • Broken throttle shaft
    • Any throttle body damage
    • If any of these conditions exist, replace the throttle body assembly.
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