The ECM performs internal tests on the microprocessor and some specific data coming into the processor.
The engine speed must be more than 1,120 RPM.
The ECM determines that an internal data test did not pass.
The ECM illuminates the malfunction indicator lamp (MIL) and records the operating conditions in the Freeze Frame on the first drive trip that the diagnostic runs and fails.
• | The ECM turns OFF the MIL after 3 consecutive drive trips that the diagnostic runs and passes. |
• | A History DTC clears after forty consecutive warm-up cycles in which no failures are reported by this or any other emission related diagnostic. |
• | The scan tool clears the MIL/DTC. |
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Values | Yes | No | ||||
---|---|---|---|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | Go to Step 2 | |||||
With a scan tool, observe the DTC information. Are any other DTCs set? | -- | Go to the applicable DTC table | Go to Step 3 | |||||
3 |
Important:
Replace the ECM. Refer to Engine Control Module Replacement/Programming . Is the action complete? | -- | Go to Step 4 | -- | ||||
4 |
Does the scan tool indicate that the diagnostic Passed? | -- | Go to Step 5 | Go to Step 2 | ||||
5 | Does the scan tool display any additional undiagnosed DTCs? | -- | Go to the applicable DTC table | System OK |