Circuit Description
The powertrain control module (PCM) used in this vehicle utilizes an electrically erasable programmable read only memory (EEPROM). The EEPROM contains program information and the calibrations required for powertrain diagnostics operation.
Unlike the programmable read only memory (PROM) used in past applications, the EEPROM is not replaceable. When the PCM is replaced or a calibration update is required, the PCM must be programmed using approved Techline equipment.
Conditions for Running the DTC
Tested during crank and PCM power up.
Conditions for Setting the DTC
The PCM does not contain the correct program required to operate the vehicle, or has not been programmed.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |
2 | Reprogram the PCM with the correct software. Refer to Powertrain Control Module Replacement . Is the action complete? | Go to Step 4 | Go to Step 3 |
Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | Go to Step 4 | -- | |
4 |
Does the DTC run and pass? | Go to Step 5 | Go to Step 3 |
5 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | System OK |
