Description
The purpose of this procedure is to satisfy the criteria necessary to execute all of the I/M readiness diagnostics. This includes completing the trips for those particular diagnostics. When all diagnostic tests are completed, the I/M System Status indicators are set to YES. Perform this test if more than one of the I/M System Status indicators is set to NO.
Conditions for Running
- The barometric pressure (BARO) is more than 75 kPa.
- The engine coolant temperature (ECT) at start-up is less than 42°C (108°F).
- The intake air temperature (IAT) is between 2-32°C (36-90°F).
- The battery voltage is between 11-15 volts.
- The fuel level is between 1/4 and 3/4.
Diagnostic Aids
Rough road conditions may prevent some of the tests from running. Extreme high or low ambient temperatures may prevent tests such as heated oxygen sensor (HO2S) heater and evaporative emission (EVAP) system from initiating. If a step is interrupted before completion, perform the remaining portion of the set procedures. Any portion of the set procedure that requires the engine at operating temperature may be repeated. This allows most of the diagnostics to run and the remaining tests can be performed using the individual System Set Procedures.
If the vehicle has recently run, start this procedure at step 3. This will allow the tests that require the engine at operating temperature to run. Using this method allows shorter cool down periods if the tests requiring a cold start do not initiate.
The scan tool can be used to monitor each of the I/M System Status indicators during the I/M Complete System Set Procedure. When all of the indicators for a test step have updated to YES, testing can move on to the next step even if the remaining portion of the test is not complete. For example, step 3 is designed to run the catalyst and HO2S tests. The procedure instructs the technician to operate the vehicle in the enable conditions for 8-10 minutes. If both tests have updated to YES within 4 minutes, it is not necessary to continue with the enable conditions and testing can advance to the next step.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
- 1: Make sure you perform the I/M system check before performing this test. Failure to do so may result in difficulty updating the status to YES.
- 2: This step is to initiate the HO2S heater tests.
- 3: This step is to run the oxygen sensor, and the catalyst tests. 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. The catalyst test will run during the specified cruise period.
- 4: This step is to run the EVAP tests. This test runs during the idle period immediately following a cruise period that meets a minimum calibrated RPM and time period.
- 5: Perform the individual system test for any of the systems that do not update to YES.
- 6: The I/M system status only reports on whether or not a diagnostic has run, not what the outcome of the test was. If any emission related DTC sets after the tests are complete, the DTC will require diagnosis.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 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 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. Preprogram the scan tool with the vehicle information before the ignition is turned ON. Ensure the vehicle is within the Conditions for Running specified in the supporting text. Turn OFF all of the accessories, e.g., A/C, blower fan, etc. Set the vehicle parking brake. Verify the transmission is in Park or Neutral. Start the engine. Allow the engine to idle for the specified time. Is the action complete? | 2 minutes | Go to Step 3 | |
| 3 | CAUTION: Refer to Road Test Caution in Cautions and Notices. In order for the next group of tests to run, the vehicle must operate in the following conditions: Acceleration at part throttle to 72-80 km/h (45-50 mph) with this speed maintained until the engine reaches operating temperature. This may be up to 8-10 minutes depending on the start up coolant temperature. Continued operation under these conditions for an additional 6 minutes. Is the action complete? | Go to Step 4 | ||
| 4 | CAUTION: Refer to Road Test Caution in Cautions and Notices. In order for the next group of tests to run, the vehicle must operate in the following conditions: Acceleration at part throttle to 90 km/h (55 mph) with this speed maintained for 2 minutes. Deceleration with the throttle closed for more than 10 seconds to 0 km/h (0 mph). Engine idling for 2 minutes while the following criteria is maintained: Service brake depressed Automatic transmission in drive Is the action complete? | Go to Step 5 | ||
| 5 | With a scan tool, observe the I/M System Status display. 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 indicated systems | |
| 6 | With a scan tool, observe the Emission Related DTC portion of the I/M System Status display. Does the scan tool indicate any Emission Related DTCs set? | Go to Diagnostic Trouble Code (DTC) List | System OK |
| 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 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. |
| CAUTION |
|---|
| Refer to Road Test Caution in Cautions and Notices. |
| CAUTION |
|---|
| Refer to Road Test Caution in Cautions and Notices. |
Inspection/Maintenance (I/M) Complete System Set Procedure