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Home >> Hummer >> 2005 >> H2 4D Utility Pickup >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Troubleshooting >> Troubleshooting >> Inspection/Maintenance (I/M) Complete System Set Procedure >> Test Description
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Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  This step is to run the HO2S heater tests and initiate the EVAP System Test. Preprogramming the scan tool will reduce the amount of time the oxygen sensor heaters operate while verifying the enable criteria.
  2. 3:  This step is to run the EVAP, the AIR, and the oxygen sensor tests. The EVAP test begins once the engine coolant reaches a calibrated temperature. The AIR test, if equipped, begins shortly after Closed Loop and the indicated speed is achieved. The oxygen sensor tests begin once the engine is at operating temperature, in Closed Loop fuel control, and a calibrated amount of time has elapsed.
  3. 4:  This step is to run the Catalyst Tests. This test runs during the idle period immediately following a cruise period that meets a minimum calibrated RPM and time period.
Inspection/Maintenance (I/M) Complete System Set Procedure

Step Action Value(s) Yes No
CAUTION: Refer to Road Test Caution in Cautions and Notices.
1 Did you perform the Inspection/Maintenance (I/M) System Check? - Go to Step 2  Go to Inspection/Maintenance (I/M) System Check 
2 
    IMPORTANT: Whenever the ignition is turned ON, ignition positive voltage is supplied to the heated oxygen sensor (HO2S) heaters. After verifying the enable criteria, turn OFF the ignition for approximately 5 minutes in order to allow the sensors to cool before continuing with the test. Once the engine is started, DO NOT turn the engine OFF for the remaining portion of the set procedure.
  1. Preprogram the scan tool with the vehicle information before the ignition is turned ON.
  2. Ensure that the vehicle is within the Conditions for Running specified in the supporting text.
  3. Turn OFF all of the accessories, including the A/C and blower fan.
  4. Set the vehicle parking brake.
  5. Verify the transmission is in Park for automatic transmissions and Neutral for manual transmissions.
  6. Start the engine and allow it to idle for the specified time.
Is the action complete?		 2 minutes Go to Step 3  -
3  In order for the next group of tests to run, the vehicle must operate in the following conditions:
  1. Acceleration at part throttle to 90 km/h (55 mph), with this speed maintained until the engine reaches operating temperature. This may be up to 10 minutes depending on the start-up coolant temperature.
  2. Continue operation under these conditions for an additional 6 minutes.

Is the action complete?		 - Go to Step 4  -
4  In order for the next group of tests to run, the vehicle must operate in the following conditions:
  1. Acceleration at part throttle to 75-89 km/h (45-55 mph) with this speed maintained for 2 minutes.
  2. Brake safely to a stop.
  3. Engine idling for 2 minutes while the following criteria are maintained:
    • Service brake depressed
    • Automatic transmission in drive
    • Manual transmission in neutral with the clutch pedal depressed

Is the action complete?		 - Go to Step 5  -
5 Observe the I/M System Status display with a scan tool.
Did all of the I/M System Status indicators update to YES?		 - Go to Step 6  Go to the I/M System Set Procedure for the systems that have not updated
6 Observe the emission related DTC portion of the I/M System Status display with a scan tool.
Does the scan tool indicate any emission related DTCs set?		 - Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information System OK
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