For 1990-2009 cars only
Circuit Description
The powertrain control module (PCM) monitors internal circuits for performance problems. If a problem is detected in the analog to digital converter circuits, DTC P1627 will set.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the 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. |
Step | Action | Yes | No |
|---|---|---|---|
1 |
Important: Before clearing the DTCs, use the scan tool Capture Info to save the Freeze Frame/Failure Records for reference. The data in the control module is deleted once the Clear Info function is used. Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |
2 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | Go to Step 3 | -- |
3 |
Does the scan tool indicate the diagnostic passed? | Go to Step 4 | Go to Step 2 |
4 | Does the scan tool display any additional undiagnosed DTCs? | System OK |
